TECHNICAL FIELD

The present disclosure relates broadly to a hyaluronic acid-based synthetic copolymer, a hyaluronic acid-based macromolecule and a material comprising said hyaluronic acid-based synthetic copolymer. The present disclosure also relates to methods of preparing said hyaluronic acid-based synthetic copolymer, said hyaluronic acid-based macromolecule and related uses.

BACKGROUND

Hyaluronic acid (HA) or hyaluronan is a linear polysaccharide without branches and is a primary component of extracellular matrix (ECM). HA can support the ECM by binding and retaining water molecules. HA contributes to tissue hydrodynamics, proliferation of cells and participates in numerous cell surface interactions. Importantly, HA acts as a signaling molecule for a variety of biological functions, such as cell adhesion, growth and migration. Due to its versatility, HA has been widely investigated for cell differentiation, migration, angiogenesis and inflammation responses for various tissue repair such as in wound healing, skin repair, bone and cartilage regeneration.

However, native/pure HA without modification tends to be absorbed rapidly in human body, undergoes rapid degradation and exhibits poor mechanical stability under physiological conditions. Physical and chemical modification studies have been performed on HA in an attempt to better control or improve its degree of degradation and mechanical strength. However, current methods have several limitations and are far from desirable.

Current material processing methods such as hydrogel formation and electrospinning of HA have drawbacks and fail to provide good control over its mechanical stability and degradation. Furthermore, such methods are also not suitable for use in long-term implantable devices. This is further elaborated below.

Currently, HA hydrogels are widely used in the biomedical industry because of its ability to form hydrogel with various chemical modifications and possess viscoelastic properties, which enables its use in various biomedical applications such as in soft tissue fillers and for cartilage regeneration and osteoarthritis treatment. However, HA hydrogels degrade rapidly due to poor mechanical stability under physiological conditions and this limitation results in low biochemical functionality for cell attachment and proliferation. HA-based hydrogels are considered bulk gels where the HA chains are randomly interconnected. Compared to natural ECM, these networks provided by HA hydrogels are not as structurally complex and functionally diverse.

Next, electrospun HA fibers have also been considered as they possess several favorable characteristics such as high specific surface area, high aspect ratio, and high porosity while maintaining very small pore size. High porosity and pore size are extremely important properties and fine-tuning of these characteristics can mimic the extracellular matrix and enhance cell migration and proliferation. HA nanofibers are believed to be better for wound healing than solid HA forms as the nanofibers could act as a scaffold to facilitate the migration and proliferation of cells in the wound. However, electrospun HA fibers face the same problems of HA being prone to rapid release and degradation. Furthermore, electrospun HA mats tends to be non-water permeable, which makes them poor materials for applications where rapid fluid transfer is required, such as in a skin substitute or wound dressing. Also, due to the rapid degradation of HA, and poor thermal and mechanical stability, HA nanofibers and hydrogels are not suitable for use in permanent medical implants or in devices that require staying in the human body for extended periods of time. It will be appreciated that currently available non- biodegradable implants could last from 15 to 20 years. On the other hand, biodegradable implants typically degrade from 8 month to 6 years.

To date, identifying a suitable material that could incorporate HA and at the same time meet mechanical requirements in order to function desirably in or with biological systems remains a challenge.

This is because HA molecules are highly hygroscopic and cannot be coated onto or blended easily with materials that can impart mechanical strength (e.g., synthetic materials). The high water solubility of HA also means that it may leach into the body and not remain on the desired site where bioactivity (e.g., tissue regeneration) is required.

On the other hand, synthetic materials that have mechanically superior characteristics lack the biological attributes needed for them to be properly used in applications that require constant interaction with biological systems. For example, a number of such synthetic material can induce foreign body reaction (FBR) when inserted into a human body. This can result in inflammation and other types of undesired immune responses being elicited around the implantation site.

Combining these different materials with the hope that the resultant material obtained can achieve both the desired HA biological and mechanical properties is also challenging. This is because HA molecules are often incompatible with synthetic polymers since the former is hydrophilic whereas the latter is hydrophobic. Thus, physically blending the two different materials together often result in phase separation of the two mutually incompatible materials, rendering the obtained entire material ineffective.

The inherent differences in their hydrophilicity likewise make chemically synthesising a HA-based polymer from these materials extremely difficult, especially when the molecular weights of these materials are relatively high. This is in addition to the various complex chemical hurdles (e.g. potentially high intramolecular reactivity, unwanted chemical leaching of by-products etc) that need to be overcome when attempting to chemically combine these two chemically different types of materials together.

In view of the above, there is a need to address or at least ameliorate the above-mentioned problems. In particular, there is a need to provide a hyaluronic acid-based synthetic copolymer, a hyaluronic acid-based macromolecule, a material comprising said hyaluronic acid-based synthetic copolymer and related methods that address or at least ameliorate the above-mentioned problems.

SUMMARY

In one aspect, there is provided a regenerative material for skin, bone and/or cartilage tissue regeneration, the material comprising, a hyaluronic acidbased synthetic copolymer having one or more repeating units represented by general formula (Vlll-a):

(Vlll-a) wherein p > 1 ; q > 1 ; x > 1 ; y > 1 ; and

Y ¹ comprises a synthetic polymer derived from polycarprolactone (PCL), polylactic acid (PLA), polyl(lactic-co-glycolic acid) (PLGA), polystyrene (PS), poly(methyl methacrylate) (PMMA), polyamide (PA) or polyacrylate.

In one embodiment, Y ¹ is selected from the following general formulae (lll-a), (lll-b), (lll-c), (lll-d), (lll-e), (lll-f) or (lll-g):

(lll-a) (lll-b) (lll-c) wherein R ⁶ is optionally substituted linear aliphatic, branched aliphatic, cyclic and/or aromatic hydrocarbons;

R ⁷ is H or CH ₃ ; m > 1 ; and n > 1.

In one embodiment, the following structure of general formula (X) contained in general formula (Vlll-a) has a weight average molecular weight of from 1 ,000 to 8,000: In one embodiment, the polyethylene glycol (PEG) comprising a structure of general formula (XI) contained in general formula (VI 11 -a) has a weight average molecular weight of from 1 ,000 to 8,000:

In one embodiment, the material is in the form of a formulation for electrospinning, melt extrusion, injection molding, compression molding, 3D printing, preparation into suspension in gels, creams, balms and/or coating.

In one embodiment, the regenerative material further comprises the hyaluronic acid-based synthetic copolymer blended with one or more synthetic base polymers.

In one embodiment, the one or more synthetic base polymers is selected from the group consisting of polycaprolactone (PCL), polylactic acid (PLA), polyl(lactic-co-glycolic acid) (PLGA), polystyrene (PS), poly(methyl methacrylate) (PMMA), polyamide (PA), polyacrylate and combinations thereof.

In one embodiment, the one or more synthetic base polymers correspond to the synthetic polymer of Y ¹ of general formula (Vlll-a).

In one aspect, there is provided a regenerative material as disclosed herein for use in aesthetic, beauty and consumer care products.

In one aspect, there is provided use of a regenerative material as disclosed herein in the manufacture of aesthetic, beauty and consumer care products.

In one aspect, there is provided a regenerative material as disclosed herein for use in medicine. In one aspect, there is provided a regenerative material as disclosed herein for use in stimulating skin, bone and/or cartilage tissue regeneration.

In one aspect, there is provided a regenerative material as disclosed herein for use in the treatment of wounds.

In one aspect, there is provided a regenerative material as disclosed herein for use in controlling and/or reducing inflammation.

In one aspect, there is provided use of a regenerative material as disclosed herein in the manufacture of a medicament for stimulating skin, bone and/or cartilage tissue regeneration.

In one aspect, there is provided use of a regenerative material as disclosed herein in the manufacture of a medicament for the treatment of wounds.

In one aspect, there is provided use of a regenerative material as disclosed herein in the manufacture of a medicament for controlling and/or reducing inflammation.

In one aspect, there is provided a method of stimulating skin, bone and/or cartilage tissue regeneration in a subject in need thereof, the method comprising applying the regenerative material as disclosed herein to a body part of the subject in need thereof.

In one aspect, there is provided a method of treating a wound, the method comprising applying the regenerative material as disclosed herein to a wound of a subject in need thereof.

In one aspect, there is provided a method of controlling and/or reducing inflammation in a subject in need thereof, the method comprising applying the regenerative material as disclosed herein to a body part of the subject in need thereof.

In one aspect, there is provided a medical device comprising the regenerative material as disclosed herein.

In one embodiment, the regenerative material has been electrospun, melt extruded, injection mold, compression mold and/or 3D printed. In one embodiment, the medical device is selected from the group consisting of skin scaffold, skin substitute, dermal matrix, dermal template, bone scaffold, cartilage scaffold, cartilage implant, bone implant, spinal fusion implant, meniscal implant, wound dressing and plaster. In one aspect, there is provided a hyaluronic acid-based macromolecule represented by general formula (IV-a) for preparing the copolymer of general formula (Vlll-

(IV-a) In one aspect, there is a method of preparing a hyaluronic acid-based macromolecule as disclosed herein, the method comprising:

(i) providing an amine having general formula (Vll-a):

(Vll-a)

(ii) reacting said amine having general formula (Vll-a) with hyaluronic acid having general formula (IX) to obtain the hyaluronic acid-based macromolecule:

DEFINITIONS

The term "polymer" as used herein refers to a chemical compound comprising repeating units and is created through a process of polymerization. The units composing the polymer are typically derived from monomers and/or macromonomers. A polymer typically comprises repetition of a number of constitutional units.

The terms “monomer” or “macromonomer” as used herein refer to a chemical entity that may be covalently linked to one or more of such entities to form a polymer.

The term “bioactive” as used herein broadly refers to the property of having a biological effect, preferably a desirable or positive biological effect on a living organism, tissue, or cell.

The term “biocompatible” as used herein broadly refers to a property of being compatible with biological systems or parts of the biological systems without substantially or significantly eliciting an adverse physiological response such as a toxic reaction, an immune reaction, an injury or the like. Such biological systems or parts include blood, cells, tissues, organs or the like.

The term "bond" refers to a linkage between atoms in a compound or molecule. The bond may be a single bond, a double bond, or a triple bond.

In the definitions of a number of substituents below, it is stated that “the group may be a terminal group or a bridging group”. This is intended to signify that the use of the term is intended to encompass the situation where the group is a terminal group/moiety as well as the situation where the group is a linker between two other portions of the molecule. Using the term “alkyl” having 1 carbon atom as an example, it will be appreciated that when existing as a terminal group, the term “alkyl” having 1 carbon atom may mean -CH3 and when existing as a bridging group, the term “alkyl” having 1 carbon atom may mean -CH2- or the like.

The term "alkyl" as a group or part of a group refers to a straight or branched aliphatic hydrocarbon group having 1 to 20 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Examples of suitable straight and branched alkyl substituents include methyl, ethyl, n-propyl, 2-propyl, isopropyl, n- butyl, isobutyl, sec-butyl, t-butyl, hexyl, amyl, 1 ,2-dimethylpropyl, 1 ,1 - dimethylpropyl, pentyl, isopentyl, hexyl, 4-methylpentyl, 1 -methylpentyl, 2- methylpentyl, 3-methylpentyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1 ,2- dimethylbutyl, 1 ,3-dimethylbutyl, 1 ,2,2-trimethylpropyl, 1 ,1 ,2-trimethylpropyl, 2- ethylpentyl, 3-ethylpentyl, heptyl, 1 -methylhexyl, 2,2-dimethylpentyl, 3,3- dimethylpentyl, 4,4-dimethylpentyl, 1 ,2-dimethylpentyl, 1 ,3-dimethylpentyl, 1 ,4- dimethylpentyl, 1 ,2,3-trimethylbutyl, 1 ,1 ,2-trimethylbutyl, 1 ,1 ,3-trimethylbutyl, 5- methylheptyl, 1 -methylheptyl, octyl, nonyl, decyl and the like. The group may be a terminal group or a bridging group.

The term "alkenyl" as a group or part of a group denotes an aliphatic hydrocarbon group containing at least one carbon-carbon double bond and which may be straight or branched having 2 to 20 carbon atoms, 2 to 10 carbon atoms, 2 to 6 carbon atoms, or 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms in the chain. The group may contain a plurality of double bonds and the orientation about each double bond is independently E or Z. Exemplary alkenyl groups include, but are not limited to, ethenyl, vinyl, allyl, 1 - methylvinyl, 1 -propenyl, 2-propenyl, 2-methyl-1 -propenyl, 2-methyl-1 -propenyl, 1 -butenyl, 2-butenyl, 3-butentyl, 1 ,3-butadienyl, 1 -pentenyl, 2-pententyl, 3- pentenyl, 4-pentenyl, 1 ,3-pentadienyl, 2,4-pentadienyl, 1 ,4-pentadienyl, 3- methyl-2-butenyl, 1 -hexenyl, 2-hexenyl, 3-hexenyl, 1 ,3-hexadienyl, 1 ,4- hexadienyl, 2-methylpentenyl, 1 -heptenyl, 2-heptentyl, 3-heptenyl, 1 -octenyl, 2- octenyl, 3-octenyl, 1 -nonenyl, 2-nonenyl, 3-nonenyl, 1 -decenyl, 2-decenyl, 3- decenyl and the like. The group may be a terminal group or a bridging group.

The term "alkynyl" as a group or part of a group denotes an aliphatic hydrocarbon group containing at least one carbon-carbon triple bond and which may be straight or branched having 2 to 20 carbon atoms, 2 to 10 carbon atoms, 2 to 6 carbon atoms, or 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms in the chain. The group may contain a plurality of triple bonds. Exemplary alkynyl groups include, but are not limited to, acetylenyl, propynyl, 1 - butynyl, 2-butynyl, 3-butynyl, 1 -pentynyl, 2-pentynyl, 3-methyl-1 -butynyl, 4- pentynyl, 1 -hexynyl, 2-hexynyl, 5-hexynyl, 1 -heptynyl, 2-heptynyl, 6-heptynyl, 1 - octynyl, 2-octynyl, 7-octynyl, 1 -nonynyl, 2-nonynyl, 8-nonynyl, 1 -decynyl, 2- decynyl, 9-decynyl and the like. The group may be a terminal group or a bridging group.

The term "heteroalkylene" as used herein refers to alkylene having one or more -CH2- replaced with a heteroatom selected from O, NR, Si, P or S, where R is hydrogen or alkyl as defined herein. The term "heteroalkylene" can be linear, branched or cyclic and containing up to 500 carbon atoms.

The term "alkoxy" as used herein refers to straight chain or branched alkyloxy groups. Examples include methoxy, ethoxy, n-propoxy, isopropoxy, tertbutoxy, and the like.

The term "alkoxyalkyl" as used herein is intended to broadly refer to a group containing -R-O-R’, where R and R’ are alkyl as defined herein. The group may be a terminal group or a bridging group.

The term "alkylcarbonyl" as used herein is intended to broadly refer to a group containing -R-C(=O)-, where R is alkyl as defined herein. The group may be a terminal group or a bridging group.

The term "alkylcarbonylalkyl" as used herein is intended to broadly refer to a group containing -R-C(=O)-R’, where R and R’ are alkyl as defined herein. The group may be a terminal group or a bridging group.

The term "carboxylalkyl" as used herein is intended to broadly refer to a group containing -C(=O)-O-R, where R is alkyl as defined herein. The group may be a terminal group or a bridging group. The term "oxycarbonylalkyl" as used herein is intended to broadly refer to a group containing -O-C(=O)-R, where R is alkyl as defined herein. The group may be a terminal group or a bridging group.

The term "alkylcarboxylalkyl" as used herein is intended to broadly refer to a group containing -R-C(=O)-O-R’, where R and R’ are alkyl as defined herein. The group may be a terminal group or a bridging group.

The term "alkoxycarbonylalkyl" as used herein is intended to broadly refer to a group containing -R-O-C(=O)-R’, where R and R’ are alkyl as defined herein. The group may be a terminal group or a bridging group.

The term "oxy" as used herein is intended to broadly refer to a group containing -O-.

The term "carbonyl" as used herein is intended to broadly refer to a group containing -C(=O)-.

The term "oxycarbonyl" as used herein is intended to broadly refer to a group containing -O-C(=O)-.

The term "carboxyl" as used herein is intended to broadly refer to a group containing -C(=O)-O-R, where R is hydrogen or an organic group.

The term "halogen" represents chlorine, fluorine, bromine or iodine. The term "halo" represents chloro, fluoro, bromo or iodo.

The term "amine group" or the like is intended to broadly refer to a group containing -NR2, where R is independently a hydrogen or an organic group. The group may be a terminal group or a bridging group. The term "amide group" or the like is intended to broadly refer to a group containing -C(=O)NR2, where R is independently a hydrogen or an organic group. The group may be a terminal group or a bridging group.

The term “optionally substituted,” when used to describe a chemical structure or moiety, refers to the chemical structure or moiety wherein one or more of its hydrogen atoms is optionally substituted with a chemical moiety or functional group such as alcohol, alkoxy, alkanoyloxy, alkoxycarbonyl, alkenyl, alkyl (e.g., methyl, ethyl, propyl, t-butyl), alkynyl, alkylcarbonyloxy (-OC(O)alkyl), amide (-C(O)NH-alkyl- or -alkylNHC(O)alkyl), amine (such as alkylamino, arylamino, arylalkylamino), aryl, aryloxy, azo, carbamoyl (-NHC(O)O-alkyl- or -OC(O)NH-alkyl), carbamyl (e.g., CONH2, as well as CONH-alkyl, CONH-aryl, and CONH-arylalkyl), carboxyl, carboxylic acid, cyano, ester, ether (e.g., methoxy, ethoxy), halo, haloalkyl (e.g., -CC , -CF3, -C(CF3)3), heteroalkyl, isocyanate, isothiocyanate, nitrile, nitro, phosphodiester, sulfide, sulfonamido (e.g., SO2NH2), sulfone, sulfonyl (including alkylsulfonyl, arylsulfonyl and arylalkylsulfonyl), sulfoxide, thiol (e.g., sulfhydryl, thioether) or urea (-NHCONH-alkyl-).

The term "micro" as used herein is to be interpreted broadly to include dimensions from about 1 micron to about 1000 microns.

The term "nano" as used herein is to be interpreted broadly to include dimensions less than about 1000 nm, less than about 500 nm, less than about 100 nm or less than about 50 nm.

The terms "coupled" or "connected" as used in this description are intended to cover both directly connected or connected through one or more intermediate means, unless otherwise stated.

The term "associated with", used herein when referring to two elements refers to a broad relationship between the two elements. The relationship includes, but is not limited to a physical, a chemical or a biological relationship. For example, when element A is associated with element B, elements A and B may be directly or indirectly attached to each other or element A may contain element B or vice versa.

The term "adjacent" used herein when referring to two elements refers to one element being in close proximity to another element and may be but is not limited to the elements contacting each other or may further include the elements being separated by one or more further elements disposed therebetween.

The term "and/or", e.g., "X and/or Y" is understood to mean either "X and Y" or "X or Y" and should be taken to provide explicit support for both meanings or for either meaning.

Further, in the description herein, the word “substantially” whenever used is understood to include, but not restricted to, "entirely" or “completely” and the like. In addition, terms such as "comprising", "comprise", and the like whenever used, are intended to be non-restricting descriptive language in that they broadly include elements/components recited after such terms, in addition to other components not explicitly recited. For example, when “comprising” is used, reference to a “one” feature is also intended to be a reference to “at least one” of that feature. Terms such as “consisting”, “consist”, and the like, may in the appropriate context, be considered as a subset of terms such as "comprising", "comprise", and the like. Therefore, in embodiments disclosed herein using the terms such as "comprising", "comprise", and the like, it will be appreciated that these embodiments provide teaching for corresponding embodiments using terms such as “consisting”, “consist”, and the like. Further, terms such as "about", "approximately" and the like whenever used, typically means a reasonable variation, for example a variation of +/- 5% of the disclosed value, or a variance of 4% of the disclosed value, or a variance of 3% of the disclosed value, a variance of 2% of the disclosed value or a variance of 1% of the disclosed value. Furthermore, in the description herein, certain values may be disclosed in a range. The values showing the end points of a range are intended to illustrate a preferred range. Whenever a range has been described, it is intended that the range covers and teaches all possible sub-ranges as well as individual numerical values within that range. That is, the end points of a range should not be interpreted as inflexible limitations. For example, a description of a range of 1% to 5% is intended to have specifically disclosed sub-ranges 1 % to 2%, 1 % to 3%, 1 % to 4%, 2% to 3% etc., as well as individually, values within that range such as 1 %, 2%, 3%, 4% and 5%. It is to be appreciated that the individual numerical values within the range also include integers, fractions and decimals. Furthermore, whenever a range has been described, it is also intended that the range covers and teaches values of up to 2 additional decimal places or significant figures (where appropriate) from the shown numerical end points. For example, a description of a range of 1 % to 5% is intended to have specifically disclosed the ranges 1.00% to 5.00% and also 1.0% to 5.0% and all their intermediate values (such as 1.01 %, 1.02% ... 4.98%, 4.99%, 5.00% and 1.1 %, 1 .2% ... 4.8%, 4.9%, 5.0% etc.,) spanning the ranges. The intention of the above specific disclosure is applicable to any depth/breadth of a range.

Additionally, when describing some embodiments, the disclosure may have disclosed a method and/or process as a particular sequence of steps. However, unless otherwise required, it will be appreciated that the method or process should not be limited to the particular sequence of steps disclosed. Other sequences of steps may be possible. The particular order of the steps disclosed herein should not be construed as undue limitations. Unless otherwise required, a method and/or process disclosed herein should not be limited to the steps being carried out in the order written. The sequence of steps may be varied and still remain within the scope of the disclosure.

Furthermore, it will be appreciated that while the present disclosure provides embodiments having one or more of the features/characteristics discussed herein, one or more of these features/characteristics may also be disclaimed in other alternative embodiments and the present disclosure provides support for such disclaimers and these associated alternative embodiments.

DESCRIPTION OF EMBODIMENTS

Exemplary, non-limiting embodiments of a hyaluronic acid-based synthetic copolymer, a hyaluronic acid-based macromolecule for preparing the hyaluronic acid-based synthetic copolymer, a regenerative material comprising the hyaluronic acid-based synthetic copolymer, related methods and related uses are disclosed hereinafter.

Hyaluronic Acid-Based Synthetic Copolymer

There is provided a hyaluronic acid-based synthetic copolymer (e.g., bioactive hyaluronic acid-based synthetic copolymer) with a poly(norbornene) backbone comprising one or more repeating units represented by general formula (I) and one or more repeating units represented by general formula (II): wherein

R ¹ is optionally substituted alkyl;

R ² is selected from a single bond, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl or optionally substituted alkylcarbonylalkyl;

R ³ is selected from H, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl;

L is heteroalkylene; x > 1 ;

Y ¹ comprises a synthetic polymer or parts thereof; and

Z ¹ and Z ² are each independently selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl.

In various embodiments, the term “hyaluronic acid-based” comprises and/or may be used interchangeably with the term “hyaluronic acid and/or derivatives thereof”, “hyaluronic acid”, “hyaluronan”, “derivatives of hyaluronic acid”, “conjugate base of hyaluronic acid” and ’’“hyaluronate”. In various embodiments, hyaluronic acid (HA) comprises a structure that is represented by general formula (IX): In various embodiments, derivative(s) of hyaluronic acid comprises a structure that is represented by general formula (X):

The derivative(s) of hyaluronic acid may be a conjugate base of hyaluronic acid or hyaluronate.

In various embodiments, the structure represented by general formula (X) (that is present in repeating unit represented by general formula (I)) has a weight average molecular weight (Mw) of from about 1 ,000 to about 8,000. For example, the structure may have a weight average molecular weight of from about 1 ,000 to about 8,000, from about 1 ,100 to about 7,900, from about 1 ,200 to about 7,800, from about 1 ,300 to about 7,700, from about 1 ,400 to about 7,600, from about 1 ,500 to about 7,500, from about 1 ,600 to about 7,400, from about 1 ,700 to about 7,300, from about 1 ,800 to about 7,200, from about 1 ,900 to about 7,100, from about 2,000 to about 7,000, from about 2,100 to about 6,800, from about 2,200 to about 6,600, from about 2,300 to about 6,400, from about 2,400 to about 6,200, from about 2,500 to about 6,000, from about 2,600 to about 5,800, from about 2,700 to about 5,600, from about 2,800 to about 5,400, from about 2,900 to about 5,200, from about 3,000 to about 5,000, from about 3,050 to about 4,950, from about 3,100 to about 4,900, from about 3,150 to about 4,850, from about 3,200 to about 4,800, from about 3,250 to about 4,750, from about 3,300 to about 4,700, from about 3,350 to about 4,650, from about 3,400 to about 4,600, from about 3,450 to about 4,550, from about 3,500 to about 4,500, from about 3,550 to about 4,450, from about 3,600 to about 4,400, from about 3,650 to about 4,350, from about 3,700 to about 4,300, from about 3,750 to about 4,250, from about 3,800 to about 4,200, from about 3,850 to about 4,150, from about 3,900 to about 4,100, from about 3,950 to about 4,050, or about 4,000. The structure represented by general formula (X) may have a weight average molecular weight of from about 1 ,168 - 7,616.

In various embodiments, x is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19 or 20.

In various embodiments, the repeating unit(s) represented by general formula (I) possess bioactivity, biocompatibility and/or biodegradability. In various embodiments, the repeating unit(s) represented by general formula (II) and/or moiety Y ¹ possess good mechanical strength/hardness. In various embodiments, the repeating unit represented by general formula (II) and/or moiety Y ¹ has a higher mechanical strength than the repeating unit represented by general formula (I). Advantageously, the presence of repeating units represented by general formulae (I) and (II) in the bioactive hyaluronic acid-based synthetic copolymer imparts both bioactivity and mechanical strength to the copolymer, leading to a mechanically strong bioactive copolymer. In various embodiments, the copolymer may also be biocompatible and/or biodegradable. Accordingly, in various embodiments, the copolymer is capable of being classified as a biomaterial. Advantageously, due to the presence of synthetic and bioactive hyaluronic acid-based side chains, the bioactive hyaluronic acid-based synthetic copolymer may also have a higher thermal stability than pure/native hyaluronic acid. Even more advantageously, the thermal stability of the bioactive hyaluronic acid-based synthetic copolymer allows for embodiments of the copolymer to be suitable for processing at high temperatures or even harsh material processing such as melt extrusion > 200 °C, making the copolymer ideal/attractive for use in applications such as biomedical devices. In various embodiments, the synthetic polymer is substantially or completely non-bioactive, or at least less bioactive than the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof).

In various embodiments, L is a polymeric linker that links the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) to the poly(norbornene) backbone. Advantageously, L is designed to be adjustable and/or customizable based on the size of the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) and the size of the synthetic polymer present in Y ¹ . The molecular weight and/or length of the polymeric linker L may be customized to suit the molecular weight and/or length of the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) and synthetic polymer chosen for Y ¹ , depending on the application the copolymer is to be used for. In various embodiments, physical properties of the macromonomer and the resultant copolymer (e.g., hyaluronic acid-based macromonomer and resultant hyaluronic acid-based synthetic copolymer) can be changed/tuned/customized depending on the length of L (e.g., PEG chain). For example, in skin scaffolds, shorter synthetic polymeric (e.g., PCL or PLA) side chains are preferred for faster degradation whereas in bone scaffolds, longer synthetic polymeric (e.g., PCL or PLA) side chains are selected for slower degradation in body. Without being bound by theory, it is believed that bone tissues are expected to grow slower than skin tissues, hence the bone scaffold needs to stay intact in the body for a longer period of time for bone tissues to regenerate and cannot degrade too quickly. For example, for applications in dressings, or particularly non-biodegradable non-woven fibers which require thermal stability and/or mechanical strength properties, low molecular weight is preferred for synthetic polymers due to their poor solubility in common solvents. In various embodiments, synthetic polymers having low molecular weight comprise synthetic polymers having molecular weight of no more than about 5,000, for example when the synthetic polymers are highly insoluble, e.g. polyamide (PA). In other embodiments, synthetic polymers having a molecular weight of no more than about 10,000 may be used/acceptable, for example, when the synthetic polymers are less insoluble.

In various embodiments, the molecular weight and/or length of the polymeric linker L is selected such that the overall molecular size of the repeating unit represented by general formula (I) is similar/comparable to the molecular size of the repeating unit represented by general formula (II). For example, if PCL having a molecular weight of 4,000 is selected as the choice of synthetic polymer for Y ¹ , then L may be designed to comprise a molecular weight of about 3,400. It will be appreciated that in various embodiments, it is the length of L that gets adjusted to match the molecular weight of general formula (I) to molecular weight of general formula (II).

In various embodiments, the molecular weight of general formula (I) is comparable/substantially similar with/to the molecular weight of general formula (II). In various embodiments, the molecular weight of general formula (I) does not differ from the molecular weight of general formula (II) by more than 30% of the molecular weight of general formula (II) or vice versa. For example, the molecular weight of general formula (I) may be at most about 30% more or at most 30% less than the molecular weight of general formula (II) or vice versa. The molecular weight of general formula (I) may not differ from the molecular weight of general formula (II) by more than about 30%, more than about 25%, more than about 20%, more than about 15%, more about 10%, more than about 5%, more than about 4%, more than about 3%, more than about 2%, or more than about 1 % of the molecular weight of general formula (II) or vice versa. In various embodiments, the molecular weight of general formula (I) does not differ from the molecular weight of general formula (II) by more than about 20% of the molecular weight of general formula (II) or vice versa. For example, the molecular weight of general formula (I) may be at most about 20% more or at most 20% less than the molecular weight of general formula (II) or vice versa. Advantageously, as the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) bearing repeating unit has a molecular size/weight/length that is similar to that of the synthetic polymer bearing repeating unit, the length of the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) is extended, thereby allowing (i.e. hyaluronic acid and/or derivatives thereof) to be “visible”, available for binding to cells or accessible to its targeted physiological site for desired bioactivity, i.e. not buried in a sea/matrix of synthetic polymers.

In various embodiments, the molecular weight of general formula (I) is about 15,000, about 14,000, about 13,000 or at least about 12,000. In various embodiments, the molecular weight of general formula (I) is from about 100 to about 15,000, from about 200 to about 14,000, from about 300 to about 13,000, from about 400 to about 12,000, from about 500 to about 11 ,000, from about 1 ,000 to about 10,000, from about 1 ,500 to about 9,500, from about 2,000 to about 9,000, from about 2,500 to about 8,500, from about 3,000 to about 8,000, from about 3,500 to about 7,500, from about 4,000 to about 7,000, from about 4,500 to about 6,500, from about 5,000 to about 6,000 or about 5,500.

In various embodiments, the molecular weight of general formula (II) is from about 100 to about 15,000, from about 200 to about 14,000, from about 300 to about 13,000, from about 400 to about 12,000, from about 500 to about 1 1 ,000, from about 1 ,000 to about 10,000, from about 1 ,500 to about 9,500, from about 2,000 to about 9,000, from about 2,500 to about 8,500, from about 3,000 to about 8,000, from about 3,500 to about 7,500, from about 4,000 to about 7,000, from about 4,500 to about 6,500, from about 5,000 to about 6,000 or about 5,500.

In various embodiments, the total molecular weight of general formula (I) and general formula (II) is kept to about 300,000, no more than about 300,000, no more than about 200,000, no more than about 100,000, no more than about 90,000, no more than about 80,000, no more than about 70,000, no more than about 60,000, no more than about 50,000, no more than about 45,000, no more than about 40,000, no more than about 35,000, no more than about 30,000, no more than about 25,000, no more than about 20,000, or no more than about 15,000 to facilitate copolymerisation.

In various embodiments, L is hydrophilic. As L is adjustable, the hydrophilicity of the repeating unit represented by general formula (I) and also the overall hydrophilicity of the bioactive hyaluronic acid-based synthetic copolymer may be adjusted as desired. Advantageously, the presence of L increases the hydrophilicity of the repeating unit represented by general formula (I) and also the overall hydrophilicity of the bioactive hyaluronic acid-based synthetic copolymer. Even more advantageously, the presence of L increases the hydrophilicity of the bioactive hyaluronic acid-based synthetic copolymer, therefore softening the synthetic polymeric chains which are hydrophobic, making the copolymer less stiff after processing. It will be appreciated by a person skilled in the art that, bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof) and synthetic polymers are typically mutually incompatible as the individual bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) is generally hydrophilic while synthetic polymer is generally hydrophobic. Advantageously, L in repeating unit represented by general formula (I) is also used to extend the chain length of the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) attached at the end of L.

In various embodiments, L is amorphous. Advantageously, the presence of L increases the amorphousness and/or decreases the crystallinity of the bioactive hyaluronic acid-based synthetic copolymer, making the copolymer useful for crafting softer or less stiff plastics such as polystyrene-based material.

In various embodiments, L is a heteroalkylene having at least 20 carbon atoms, at least 30 carbon atoms, at least 40 carbon atoms, at least 50 carbon atoms, at least 60 carbon atoms, at least 70 carbon atoms, at least 80 carbon atoms, at least 90 carbon atoms, at least 100 carbon atoms, at least 150 carbon atoms, at least 200 carbon atoms, at least 250 carbon atoms or at least 300 carbon atoms. In various embodiments, L is C20-C300 heteroalkylene or a heteroalkylene having from 20 carbon atoms to 300 carbon atoms.

In various embodiments, L has a number/weight average molecular weight of between about 500 and about 7,000. L may have a number/weight average molecular weight of about 600, about 700, about 800, about 900, about 1 ,000, about 1 ,500, about 2,000, about 2,500, about 3,000, about 3,500, about 4,000, about 4,500, about 5,000, about 5,500, about 6,000, about 6,500 or about 7,000. In various embodiments, when the bioactive moiety (i.e. hyaluronic acid and/or derivatives there) in general formula (I) is small, the molecular weight of L may be adjusted to about 7,000 so that the total molecular weight of general formula (I) and general formula (II) is kept to no more than about 10,000. In various embodiments, the number/weight average molecular weight of L is from about 1 ,000 to about 6,000.

In various embodiments, the heteroatom in L is O. In various embodiments, L is polyalkylene glycol. In various embodiments, L is poly(C2-C4 alkylene glycol). L may be selected from the group consisting of polyethylene glycol (PEG), polypropylene glycol (PPG), polytetramethylene glycol (PTMG), polybutylene glycol (PBG) and the like. Advantageously, the use of a polyalkylene glycol such as PEG can increase hydrophilicity and/or thermal stability of the macromonomer and the resultant copolymer. In various embodiments, the polyalkylene glycol such as PEG are used as spacers, linkers or linking groups in the overall polymers, instead of as terminal groups.

In various embodiments, L is polyalkylene glycol having at least about 10 repeating units, at least about 15 repeating units, at least about 20 repeating units, at least about 21 repeating units, at least about 22 repeating units, at least about 23 repeating units, at least about 24 repeating units, at least about 25 repeating units, at least about 30 repeating units, at least about 40 repeating units, at least about 50 repeating units, at least about 60 repeating units, at least about 70 repeating units, at least about 80 repeating units, at least about 90 repeating units, at least about 100 repeating units, at least about 150 repeating units, at least about 200 repeating units, or at least about 250 repeating units. In various embodiments, L comprises from about 10 monomers/repeating units to about 250 monomers/repeating units. Unlike conventional polymers which uses a short PEG chain, embodiments of the bioactive hyaluronic acid-based synthetic copolymer disclosed herein incorporate a long polyalkylene glycol chain of at least 21 repeating units at L.

In various embodiments, L is selected from the group consisting of PEGsoo, PEGeoo, PEG700, PEGsoo, PEG900, PEG1000, PEG1100, PEG1200, PEG1300, PEG1400, PEG1500, PEG2000, PEG2500, PEG3000, PEG ₃ ,4OO, PEG3500, PEG4000, PEG4500, PEG5000, PEG5500, PEGsooo, PEGssoo, PEGsooo and mixtures thereof.

In various embodiments, hyaluronic acid and/or derivatives thereof is coupled to the poly(norbornene dicarboximide) backbone via peptide/amide linkage, i.e. -NR ³ -C(=O)-. Advantageously, the bioactive hyaluronic acid-based synthetic copolymer disclosed herein is considerably stronger and/or stable than conventional polymers that contain ester linkages. Without being bound by theory, it is believed that amide linkages are stronger than ester linkages because ester linkages are more prone to hydrolysis, which may release bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof) into the bloodstream, leading to a premature metabolism of bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof). Advantageously, the presence of an amide linkage prevents the hyaluronic acid and/or derivatives thereof from breaking off from the polymer chain, therefore ensuring the bioavailability of the hyaluronic acid and/or derivatives thereof. It will be appreciated that the active site for bioactivity (e.g, cell binding) is at the hyaluronic acid and/or derivatives thereof in general formula (!)■ In various embodiments, one or more of H atoms in alkyl, alkenyl, alkynyl, alkoxyalkyl, alkylcarbonyl and alkylcarbonylalkyl is/are optionally replaced by hydroxy, hydroxyalkyl, halogen, haloalkyl, cyano, cyanoalkyl and nitro.

In various embodiments, R ¹ is selected from C1-C20 alkyl. The C1-C20 alkyl substituents may be straight or branched substituents selected from methyl, ethyl, n-propyl, 2-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, hexyl, amyl, 1 ,2-dimethylpropyl, 1 ,1 -dimethylpropyl, pentyl, isopentyl, hexyl, 4-methylpentyl, 1 -methylpentyl, 2-methylpentyl, 3-methylpentyl,

2.2-dimethylbutyl, 3,3-dimethylbutyl, 1 ,2-dimethylbutyl, 1 ,3-dimethylbutyl,

1 .2.2-trimethylpropyl, 1 ,1 ,2-trimethylpropyl, 2-ethylpentyl, 3-ethylpentyl, heptyl, 1 -methylhexyl, 2,2-dimethylpentyl, 3,3-dimethylpentyl, 4,4-dimethylpentyl,

1 .2-dimethylpentyl, 1 ,3-dimethylpentyl, 1 ,4-dimethylpentyl, 1 ,2,3-trimethylbutyl,

1 .1 .2-trimethylbutyl, 1 ,1 ,3-trimethylbutyl, 5-methylheptyl, 1 -methylheptyl, octyl, nonyl, decyl or the like. R ¹ may be straight or branched C1-C4 alkyl substituents. In various embodiments, the length of R ¹ is the same as the length of a repeating unit in L. For example, if L is poly(butylene glycol), then R ¹ is butyl. In another example, if L is polyethylene glycol), then R ¹ is ethyl. It will be appreciated that in various embodiments, R ¹ is carefully designed to match L.

In various embodiments, R ³ is selected from H, C1-C20 alkyl, C2-C20 alkenyl or C2-C20 alkynyl.

In various embodiments, Z ¹ and Z ² are each independently selected from CH2, O, NH, SiR ^a R ^b , PR ^a or S. The poly(norbornene) backbone may be selected from the group consisting of poly(norbornene-imide), poly(norbornene- dicarboximide), poly(norbornene) backbone is poly(5-norbornene-2,3- dicarboximide), poly(7-oxanorbornene), poly(oxanorbornene-imide), poly(oxanorbornene-dicarboximide) and the like. In various embodiments, Z ¹ and Z ² are each independently selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b , and R ^c are each independently selected from the group consisting of H, C1-C20 alkyl, C1-C20 alkenyl and Ci-C2o alkynyl. In various embodiments, Z ¹ is CH2. In various embodiments, Z ² is CH2.

In various embodiments, as a carboxylic acid is naturally present in hyaluronic acid, no modification may be required/necessary to the hyaluronic acid for linking to the poly(norbornene dicarboximide) backbone.

In various embodiments, the repeating unit represented by general formula (I) is in an amount of from about 1 molar % to about 100 molar %, from about 2 molar % to about 99 molar %, from about 3 molar % to about 98 molar %, from about 4 molar % to about 97 molar %, from about 5 molar % to about 96 molar %, from about 10 molar % to about 95 molar %, from about 15 molar % to about 90 molar %, from about 20 molar % to about 85 molar %, from about 25 molar % to about 80 molar %, from about 30 molar % to about 75 molar %, from about 35 molar % to about 70 molar %, from about 40 molar % to about 65 molar %, from about 45 molar % to about 60 molar %, or from about 50 molar % to about 55 molar % relative to the copolymer. In various embodiments, the repeating unit represented by general formula (I) is in an amount of from about 1 molar % to about 10 molar % relative to the copolymer. In various embodiments, the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) is about 2 molar %, about 3 molar %, about 4 molar %, about 5 molar %, about 6 molar %, about 7 molar %, about 8 molar %, about 9 molar % or about 10 molar % of the bioactive hyaluronic acid-based synthetic copolymer.

In various embodiments, R ² is selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C1-C20 alkoxyalkyl, C2-C20 alkylcarbonyl or C3-C20 alkylcarbonylalkyl. The C1-C20 alkyl substituents may be straight or branched substituents selected from methyl, ethyl, n-propyl, 2-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, hexyl, amyl, 1 ,2-dimethylpropyl, 1 ,1 -dimethylpropyl, pentyl, isopentyl, hexyl, 4-methylpentyl, 1 -methylpentyl, 2-methylpentyl, 3-methylpentyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1 ,2-dimethylbutyl, 1 ,3-dimethylbutyl, 1 ,2,2-trimethylpropyl, 1 ,1 ,2-trimethylpropyl, 2-ethylpentyl, 3-ethylpentyl, heptyl, 1 -methylhexyl, 2,2-dimethylpentyl, 3,3-dimethylpentyl, 4,4-dimethylpentyl, 1 ,2-dimethylpentyl, 1 ,3-dimethylpentyl, 1 ,4-dimethylpentyl, 1 ,2,3-trimethylbutyl, 1 ,1 ,2-trimethylbutyl, 1 ,1 ,3-trimethylbutyl, 5-methylheptyl, 1 -methylheptyl, octyl, nonyl, decyl or the like.

In various embodiments, Y ¹ is represented by general formula (III): wherein

A is selected from a single bond, oxy, carbonyl, oxycarbonyl, carboxyl, optionally substituted alkoxy, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl, optionally substituted alkylcarbonylalkyl, optionally substituted carboxyalkyl, optionally substituted oxycarbonylalkyl, optionally substituted alkylcarboxylalkyl, or optionally substituted alkoxycarbonylalkyl;

B is optionally present as a ring selected from 1 ,2,3-triazole or succinimide;

R ⁵ is selected from a single bond, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl or optionally substituted alkylcarbonylalkyl;

Y ² is selected from the group consisting of polypropylene (PP), polyesters, poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA), poly(caprolactone) (PCL), polystyrene (PS), polyacrylates, poly(meth)acrylates, polyamides (PA) and parts thereof; and

T is a terminal group selected from the group consisting of hydrogen, halogen, hydroxyl, amino, acyl, thiol, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl, optionally substituted alkylcarbonylalkyl, optionally substituted carboxyalkyl, optionally substituted oxycarbonylalkyl, optionally substituted alkylcarboxylalkyl and optionally substituted alkoxycarbonylalkyl.

In various embodiments, Y ² is a polyacrylate comprising one or more monomers selected from the group consisting of methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, benzyl acrylate and phenyl acrylate. Y ² may be poly(methyl acrylate), poly(ethyl acrylate), poly(butyl acrylate) or poly (2-ethylhexyl acrylate). In various embodiments, Y ² is a poly(meth)acrylate comprising one or more monomers selected from the group consisting of methyl methacrylate, ethyl methacrylate, n- propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate and phenyl methacrylate. Y ² may be poly(methyl methacrylate) (PMMA), poly(ethyl methacrylate) and poly(butyl methacrylate) or poly (2-ethylhexyl acrylate).

In various embodiments, A is selected from a single bond, oxy, carbonyl or oxycarbonylalkyl. A may be a single bond, O, C(=O) and O-C(=O)-R, wherein R is optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl. In various embodiments, R is straight or branched alkyl substituents selected from methyl, ethyl, n-propyl, 2-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, hexyl, amyl, 1 ,2-dimethylpropyl, 1 ,1 -dimethylpropyl, pentyl, isopentyl, hexyl, 4-methylpentyl, 1 -methylpentyl, 2-methylpentyl, 3- methylpentyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1 ,2-dimethylbutyl, 1 ,3- dimethylbutyl, 1 ,2,2-trimethylpropyl, 1 ,1 ,2-trimethylpropyl, 2-ethylpentyl, 3- ethylpentyl, heptyl, 1 -methylhexyl, 2,2-dimethylpentyl, 3,3-dimethylpentyl, 4,4- dimethylpentyl, 1 ,2-dimethylpentyl, 1 ,3-dimethylpentyl, 1 ,4-dimethylpentyl, 1 ,2,3- trimethylbutyl, 1 ,1 ,2-trimethylbutyl, 1 ,1 ,3-trimethylbutyl, 5-methylheptyl, 1 - methylheptyl, octyl, nonyl, decyl or the like. In various embodiments, A is selected from a single bond, O, C(=O) or O-C(=O)-Ci-Ce alkyl. In various embodiments, B is absent. In various embodiments, B is present as a ring selected from 1 ,2,3-triazole or succinimide. Advantageously, 1 ,2,3- triazole is suitable for connectivity with the present system because of the chemistry used. For example, azide-alkyne click chemistry forms 1 ,2,3-triazole, which links the norbornene dicarboximide to synthetic polymer Y ² . Advantageously, succinimide is suitable for connectivity with the present system because of the chemistry used. For example, maleic acid anhydride addition on vinyl-terminated polyolefin forms succinimic acid anhydride, which then reacts with an amine terminal created on norbornene dicarboximide (via hexamethylenediamine (HMDA) or similar diamines) to form succinimide, which links the norbornene dicarboximide to synthetic polymer Y ² .

In various embodiments, R ⁵ is selected from a single bond, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl. R ⁵ may be a single bond or straight or branched alkenyl substituents selected from ethenyl, vinyl, allyl, 1 -methylvinyl, 1 -propenyl, 2-propenyl, 2-methyl-1 - propenyl, 2-methyl-1 -propenyl, 1 -butenyl, 2-butenyl, 3-butentyl, 1 ,3-butadienyl, 1 -pentenyl, 2-pententyl, 3-pentenyl, 4-pentenyl, 1 ,3-pentadienyl, 2,4-pentadienyl, 1 ,4-pentadienyl, 3-methyl-2-butenyl, 1 -hexenyl, 2-hexenyl, 3-hexenyl, 1 ,3- hexadienyl, 1 ,4-hexadienyl, 2-methylpentenyl, 1 -heptenyl, 2-heptentyl, 3- heptenyl, 1 -octenyl, 2-octenyl, 3-octenyl, 1 -nonenyl, 2-nonenyl, 3-nonenyl, 1 - decenyl, 2-decenyl, 3-decenyl or the like. In various embodiments, R ⁵ is selected from a single bond or C2-C6 alkenyl.

In various embodiments, Y ² is selected from the group consisting of polypropylene (PP), polyesters, poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA), poly(caprolactone) (PCL), polystyrene (PS), polyacrylates, poly(meth)acrylates, polyamides (PA), and parts thereof. In various embodiments, Y ² comprises one or more of the following properties: bioresorbable; inert; long shelf life; mechanical strength; impact resistant; thermal stability; elasticity; elastic recovery; smoothness; biodegradable; lightweight; and low or non-toxicity. In various embodiments, Y ² is substantially devoid of polyalkylene glycol such as polyethylene glycol.

In various embodiments, T is a terminal group selected from the group consisting of hydrogen, halogen, hydroxyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkylcarboxylalkyl and optionally substituted alkoxycarbonylalkyl. T may be H, OH, halogen selected from Cl, F, Br, I, Ci-Ce alkyl, Ci-Ce alkyl-C(=O)-O-Ci-C6 alkyl or Ci-Ce alkyl-O- C(=O)-Ci-Ce alkyl.

In various embodiments, Y ¹ is selected from the following general formulae (Illa), ( 11 lb) , (I I Ic) , (Hid), (Hie) or (I I If), wherein n > 1 ; and m > 1 : In various embodiments, n is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36,

37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54, 55, 56, 57,

58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75, 76, 77, 78,

79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96, 97, 98, 99,

100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 1 10, 1 11 , 1 12, 113, 1 14, 115,

1 16, 1 17, 1 18, 1 19, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 ,

132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147,

148, 149 or 150. In various embodiments, m is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12,

13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33,

34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54,

55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75,

76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96,

97, 98, 99, 100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 1 10, 1 11 , 1 12, 1 13, 1 14, 1 15, 1 16, 1 17, 1 18, 119, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 , 132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147, 148, 149 or 150.

In various embodiments, the total molecular weight of general formula (II) is kept to no more than about 15,000 or no more than about 10,000. It will be appreciated that copolymerisation may become inefficient when the total molecular weight of general formula (I) and (II) is too high. In various embodiments, when the bioactive hyaluronic acid-based synthetic copolymer is used for applications which require fast biodegradation, the molecular weight of general formula (II) is kept low by adjusting the value of n and/or m. In various embodiments, R ² -Y ¹ is selected from the following, wherein n > 1 ; and m > 1 :

In various embodiments, the ratio of the number of repeating units represented by general formula (I) to the number of repeating units represented by general formula (II) in the bioactive hyaluronic acid-based synthetic copolymer is from about 1 :1 to about 1 :100, from about 1 :2 to about 1 :99, from about 1 :3 to about 1 :98, from about 1 :4 to about 1 :97, from about 1 :5 to about 1 :96, from about 1 :6 to about 1 :95, from about 1 :7 to about 1 :90, from about 1 :8 to about 1 :85, from about 1 :9 to about 1 :80, from about 1 :10 to about 1 :75, from about 1 :15 to about 1 :70, from about 1 :20 to about 1 :65, from about 1 :25 to about 1 :60, from about 1 :30 to about 1 :55, from about 1 :35 to about 1 :50, or from about 1 :40 to about 1 :45. In various embodiments, the ratio of the number of repeating units represented by general formula (I) to the number of repeating units represented by general formula (II) in the bioactive hyaluronic acid-based synthetic copolymer is about 1 :10, about 1 :15, about 1 :20, about 1 :25, about 1 :30, about 1 :35, about 1 :40, about 1 :45 or about 1 :50. In various embodiments, the number of repeating units represented by general formula (I) in the copolymer is from about 10 to about 1 ,000. In various embodiments, the number of repeating units represented by general formula (II) in the copolymer is from about 10 to about 1 ,000. In various embodiments, for bone scaffold construction, PLA side chains comprise from about 50 to about 60 lactide units.

In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer has a number average molecular weight (Mn) of from about 1 ,000 to about 300,000, 2,000 to about 250,000, from about 3,000 to about 200,000, from about 4,000 to about 150,000, from about 5,000 to about 100,000, from about 10,000 to about 90,000, from about 20,000 to about 80,000, from about 30,000 to about 70,000, from about 40,000 to about 60,000, or about 50,000.

In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer has a polydispersity index (PDI) of from about 1.0 to about 10.0. In various embodiments, PDI of the bioactive hyaluronic acid-based synthetic copolymer is about 1.0, about 1.5, about 2.0, about 2.5, about 3.0, about 3.5, about 4.0, about 4.5, about 5.0, about 5.5, about 6.0, about 6.5, about 7.0, about 7.5, about 8.0, about 8.5, about 9.0, about 9.5 or about 10.0. In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer has a polydispersity index (PDI) of from about 1 .0 to about 3.0, from about 1 .05 to about 2.95, from about 1 .1 to about 2.9, from about 1 .2 to about 2.8, from about 1 .4 to about 2.6, from about 1 .6 to about 2.4, from about 1 .8 to about 2.2 or about 2.0. In various embodiments, the PDI of the bioactive hyaluronic acid-based synthetic copolymer is no more than 1 .50.

In various embodiments, the one or more repeating units represented by general formula (I) and the one or more repeating units represented by general formula (II) are designed to link to the poly(norbornene) backbone via at least covalent interactions. In various embodiments, each repeating unit represented by general formula (I) is covalently bonded to the poly(norbornene) backbone and/or each repeating unit represented by general formula (II) is covalently bonded to the poly(norbornene) backbone. Advantageously, as bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof in general formula (I)) are covalently bonded to the bioactive hyaluronic acid-based synthetic polymer, bioactivity is localized. In various embodiments, the bioactive moieties such as hyaluronic acid-based biomolecules do not leach out from the polymer, therefore preventing undesirable/unwanted side effects caused by hyaluronic acid-based biomolecules entering the circulatory system and/or reaching unintended parts of the body system.

It will be appreciated that other interactions such as Van der Waals interactions may also be present within the copolymer.

In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer comprises a brush, bottlebrush, block, comb or graft-copolymer structure. In various embodiments, the repeating units may be randomly distributed/arranged within the polymer.

In various embodiments, the one or more repeating units represented by general formula (II) comprises two or more different types of synthetic polymer Y ² . In various embodiments, the one or more repeating units represented by general formula (II) comprises 2, 3, 4, 5, 6, 7 or 8 different types of synthetic polymer Y ² .

In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer is a random polymer or a block copolymer. In some embodiments, the block polymer is a di-block or a triblock polymer. For example, the copolymer may have or is made up of two or three different polymer blocks. In some embodiments, the multi-block copolymer comprises more than three polymeric blocks. The blocks may be randomly distributed/arranged within the polymer. In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer is selected from one of the following: PCL-PEGHA copolymer comprising pegylated HA in general formula (I) and PCL in general formula (II); PA-PEGHA copolymer comprising pegylated HA in general formula (I) and PA in general formula (II); PS-PEGHA copolymer comprising pegylated HA in general formula (I) and PS in general formula (II); PLA-PEGHA copolymer comprising pegylated HA in general formula (I) and PLA in general formula (II); PLGA- PEGHA copolymer comprising pegylated HA in general formula (I) and PLGA in general formula (II); and PMMA-PEGHA copolymer comprising pegylated HA in general formula (I) and PMMA in general formula (II).

In various embodiments, the copolymer is represented by general formula (VIII): wherein p > 1; q > 1 ; x > 1 ; and y > 1. In various embodiments, p is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36,

37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54, 55, 56, 57,

58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75, 76, 77, 78,

79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96, 97, 98, 99,

100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 110, 111 , 112, 113, 114, 115,

116, 117, 118, 119, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 ,

132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147,

148, 149 or 150. In various embodiments, q is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33,

34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54,

55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75,

76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96,

97, 98, 99, 100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 110, 111 , 112, 113, 114, 115, 116, 117, 118, 119, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129,

130, 131 , 132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145,

146, 147, 148, 149 or 150. In various embodiments, x is 1 , 2, 3, 4, 5, 6, 7, 8, 9,

10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20. In various embodiments, y is 1 , 2, 3,

4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26,

27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47,

48, 49, 50, 51 , 52, 53, 54, 55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68,

69, 70, 71 , 72, 73, 74, 75, 76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89,

90, 91 , 92, 93, 94, 95, 96, 97, 98, 99, 100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 110, 111 , 112, 113, 114, 115, 116, 117, 118, 119, 120, 121 , 122, 123,

124, 125, 126, 127, 128, 129, 130, 131 , 132, 133, 134, 135, 136, 137, 138, 139,

140, 141 , 142, 143, 144, 145, 146, 147, 148, 149, 150, 151 , 152, 153, 154, 155,

156, 157, 158, 159, 160, 161 , 162, 163, 164, 165, 166, 167, 168, 169, 170, 171 ,

172, 173, 174, 175, 176, 177, 178, 179, 180, 181 , 182, 183, 184, 185, 186, 187,

188, 189, 190, 191 , 192, 193, 194, 195, 196, 197, 198, 199 or 200.

Advantageously, the bioactive hyaluronic acid-based synthetic copolymer disclosed herein is highly customizable. Depending on the application that the bioactive hyaluronic acid-based synthetic copolymer is intended, Y ² with the desired physical attributes may be selected to eventually obtain the bioactive hyaluronic acid-based synthetic copolymer with the desired repeating units represented by general formulae (II).

In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer is blended with a base polymer for further use. In various embodiments, the base polymer is similar to or of the same type as the synthetic polymer Y ² used in general formula (II). In various embodiments, a medical grade polymer is used for base material while low molecular weight synthetic polymer is used in the synthetic side chain of the bioactive hyaluronic acid-based synthetic copolymer. Advantageously, embodiments of the bioactive hyaluronic acid-based synthetic polymer allow for the hyaluronic acid-based biomolecule to be blended into base material of synthetic polymer similar to the synthetic polymer side arms of copolymer, without phase separation.

Advantageously, the bioactive hyaluronic acid-based synthetic copolymer structure provides better/improved solubility of HA molecules in organic solvents for material processing using methods such as electrospinning or formulation and enhances the thermal stability of HA for high temperature material processing methods such as injection molding, compression molding, melt extrusion and 3D printing.

In various embodiments, the bioactive hyaluronic acid-based synthetic copolymer is substantially devoid of stem cells and/or growth factor. In various embodiments, the bioactive synthetic copolymer is non-biofouling.

In various embodiments, the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) is directly chemically linked to the copolymer. In various embodiments, the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) is not being encapsulated in the polymer matrix. In various embodiments, the bioactive moiety (i.e. hyaluronic acid and/or derivatives thereof) is not connected to the norbornene dicarboximide via an amino butyric acid spacer.

In various embodiments, polyethylene glycol is not used as a monomer on its own. For example, in various embodiments ethylene glycol units are not present in the copolymer/macromolecule as terminal groups.

Embodiments of the bioactive hyaluronic acid-based synthetic polymer and/or methods disclosed herein do not involve any release of bioactive hyaluronic acid-based molecule from the copolymer on activation methods such as photoactivation. Embodiments of the bioactive synthetic polymer is substantially devoid of a photocleavable group.

Methods of preparing a bioactive hyaluronic acid-based synthetic

There is provided a method of preparing a bioactive hyaluronic acid-based synthetic copolymer, the method comprising: polymerizing one or more bioactive macromolecules represented by general formula (IV) with one or more synthetic macromolecules represented by general formula (V) to obtain the bioactive hyaluronic acid-based synthetic copolymer:

wherein R ¹ is optionally substituted alkyl;

R ² is selected from a single bond, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl or optionally substituted alkylcarbonylalkyl; R ³ is selected from H, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl;

L is heteroalkylene; x > 1 ;

Y ¹ comprises a synthetic polymer or parts thereof; and Z ¹ and Z ² are each independently selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl.

Advantageously, in various embodiments, the method of preparing a bioactive hyaluronic acid-based synthetic copolymer as disclosed herein is also a modular method for designing a bioactive hyaluronic acid-based synthetic copolymer.

There is also provided a modular method of designing a bioactive hyaluronic acid-based synthetic copolymer, the method comprising: selecting one or more hyaluronic acid-based macromolecules from a first module based on desired length/size, the first module consisting of a library of norbornene- dicarboximide-containing bioactive hyaluronic acid-based macromolecules represented by general formula (IV) with known biological activities; selecting one or more macromolecules from a second module based on desired physical attributes, the second module consisting of a library of norbornene- dicarboximide-containing synthetic macromolecules represented by general formula (V) with known physical attributes; and polymerizing the one or more hyaluronic acid-based macromolecules selected from the first module with the one or more macromolecules selected from the second module to obtain the bioactive hyaluronic acid-based synthetic copolymer:

Advantageously, the methods disclosed herein allow rapid customization and quick development/construction of the bioactive hyaluronic acid-based synthetic copolymer with the desired bioactivity and physical properties.

In various embodiments, the polymerization reaction comprises one or more olefin metathesis chain-growth polymerization step(s). The olefin metathesis chain-growth polymerization may be ring opening metathesis polymerization (ROMP). In various embodiments, the ROMP reaction occurs at the reactive moiety of the hyaluronic acid-based macromonomers, for e.g., at the olefins/alkene/C=C moieties. The ROMP may comprise a number of different approaches, including “arm-first” ROMP, “brush-first” ROMP, “graft-to” ROMP, “graft-from” ROMP, “graft-through” ROMP, or combinations thereof. Advantageously, ROMP allows quick development/construction of well-defined synthetic polymers with the desired HA bioactivities. In various embodiments, depending on the targeted application, an appropriate synthetic polymer may be chosen and copolymerized together with hyaluronic acid-based biomolecule using ROMP.

In various embodiments, the polymerization reaction is performed in the presence of a polymerisation initiator/catalyst/promoter. In various embodiments, the polymerisation initiator/catalyst/promoter comprises a metal complex. The metal complex may be a ruthenium (Ru), molybdenum (Mo) or tungsten (W) complex. In various embodiments, ROMP is performed in the presence of a ruthenium complex. Advantageously, as compared to other transition metals (e.g., W and Mo), Ru is more stable in the presence of polar functional groups, thereby making Ru a suitable olefin metathesis catalyst for ROMP reactions that involve hyaluronic acid and/or derivatives thereof. In various embodiments, Ru is air-stable (i.e. stable in air) and thermally stable (i.e. stable at high temperatures) whilst being commercially available on a large scale, allowing ROMP to be carried out at elevated temperatures. The ruthenium complex may comprise a Grubbs catalyst selected from a first-generation Grubbs catalyst, second-generation Grubbs catalyst, Hoveyda-Grubbs’ catalyst, a third-generation Grubbs catalyst or derivatives thereof.

In various embodiments, R ¹ , R ² , R ³ , L, x, Y ¹ , Z ¹ and Z ² contain one or more features and/or share one or more properties that are similar to those described above.

In various embodiments, the polymerization reaction comprises a) mixing one or more bioactive hyaluronic acid-based macromolecules represented by general formula (IV) with one or more synthetic macromolecules represented by general formula (V) to obtain a solution; b) adding the catalyst to the solution from a); and c) precipitating the bioactive hyaluronic acid-based synthetic copolymer. In various embodiments, step a) and/or step b) is/are carried out or undertaken at a temperature in the range of from about 20 °C to about 100 °C. The temperature(s) at which step a) and step b) is carried out may be independently selected from a temperature of about 20 °C, about 25 °C, about 30 °C, about 35 °C, about 40 °C, about 50 °C, about 60 °C, about 70 °C, about 80 °C, about 90 °C or about 100 °C.

In various embodiments, step a) and/or step b) is/are carried out or undertaken for a time period in the range of from about 30 mins to about 3 days. The time period at which step a) and step b) is carried out may be independently selected from a time period of about 30 mins, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 10 hours, 20 hours, 1 day, 2 days or 3 days.

In various embodiments, step a) and/or step b) is/are carried out in the presence of an organic solvent. The organic solvent may be a protic solvent, an aprotic solvent or combinations thereof. In various embodiments, the organic solvent(s) for step a) and step b) is independently selected from the group consisting of tetrahydrofuran (THF), benzene, toluene, acetonitrile (ACN), dichloromethane (DCM), dimethyl sulfoxide (DMSO), acetone, methyl ethyl ketone (MEK), formic acid, acetic acid and the like and combinations thereof. In various embodiments, protic solvents such as formic acid and/or acetic acid may be used especially for PA-based materials (e.g. when Y ¹ comprises formula lllf). In various embodiments, the organic solvent used is the same for step a) and b). It is to be appreciated that the type of solvent used is dependent on the type of reactants used and is not limited to the above.

In various embodiments, step c) is/are carried out in a mixture of organic solvents. The mixture of organic solvents may contain one or more aprotic organic solvents and one or more protic organic solvents. In various embodiments, the mixture of organic solvents for step c) is selected from the group consisting of tetrahydrofuran (THF), benzene, toluene, acetonitrile (ACN), dichloromethane (DCM), dimethyl sulfoxide (DMSO), acetone, methyl ethyl ketone (MEK), ethyl vinyl ether, methanol, ethanol, butanol and the like and combinations thereof. It is to be appreciated that the type of solvent used is dependent on the type of reactants used and is not limited to the above.

Advantageously, by carrying out polymerization with the carefully designed/controlled conditions described above, embodiments of the method disclosed herein have successfully overcome the widely varying and/or opposing properties of the individual components (e.g., L, hyaluronic acid and/or derivatives thereof, Y components) to construct the bioactive hyaluronic acidbased synthetic copolymer disclosed herein.

There is also provided a method of preparing a bioactive hyaluronic acidbased homopolymer, the method comprising: polymerising one or more bioactive hyaluronic acid-based macromolecules represented by general formula (IV) to obtain the bioactive hyaluronic acid-based homopolymer: wherein R ¹ is optionally substituted alkyl; R ³ is selected from H, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl; L is heteroalkylene; x > 1 ; and Z ¹ is selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl.

There is also provided a method of preparing a synthetic homopolymer, the method comprising: polymerising one or more synthetic macromolecules represented by general formula (V) to obtain the synthetic homopolymer: wherein R ² is selected from a single bond, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl or optionally substituted alkylcarbonylalkyl; Y ¹ comprises a synthetic polymer or parts thereof; and Z ² is selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl.

Hyaluronic Acid-Based Macromolecule

There is also provided a bioactive hyaluronic acid-based macromolecule represented by general formula (IV) for preparing the copolymer disclosed herein: wherein

R ¹ is optionally substituted alkyl;

R ³ is selected from H, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl;

L is heteroalkylene; x > 1 ; ; and

Z ¹ is selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl.

In various embodiments, R ¹ , R ³ , L, x and Z ¹ contain one or more features and/or share one or more properties that are similar to those already described above. In various embodiments, the bioactive hyaluronic acid-based macromer is represented by general formula (IV-a):

(IV-a) In various embodiments, the bioactive hyaluronic acid-based macromolecule undergoes self-polymerization or co-polymerization. In various embodiments thereof, the bioactive macromolecule also behaves as a bioactive macromonomer. In various embodiments, hyaluronic acid and/or derivatives thereof is coupled to the norbornene dicarboximide via peptide/amide linkage, i.e. -NR ³ - C(=O)-. Advantageously, the bioactive macromolecule disclosed herein is considerably stronger and/or stable than conventional macromolecules that contain ester linkages. Without being bound by theory, it is believed that amide linkages are stronger than ester linkages because ester linkages are more prone to hydrolysis, which may release bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof) into the bloodstream, leading to a premature metabolism of bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof). Advantageously, the presence of an amide linkage prevents the hyaluronic acid and/or derivatives thereof from breaking off from the polymer chain, therefore ensuring the bioavailability of the hyaluronic acid and/or derivatives thereof. It will be appreciated that the active site for bioactivity (e.g, cell binding) is at the hyaluronic acid and/or derivatives thereof in general formula (I).

Methods of preparing a bioactive hyaluronic acid-based macromolecule

There is also provided a method of preparing a bioactive hyaluronic acidbased macromolecule disclosed herein, the method comprising: (i) providing a dicarboxylic anhydride having general formula (VI): wherein Z ¹ is selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl; (ii) reacting said dicarboxylic anhydride having general formula (VI) with a diamine R ⁴ R ³ N-L-R ¹ -NH2 to obtain an amine having general formula (VII): wherein R ¹ is optionally substituted alkyl; R ³ and R ⁴ are each independently selected from H, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl, wherein at least one of R ³ and R ⁴ is H; L is heteroalkylene; Z ¹ is selected from CR ^a R ^b , O, NR ^C , SiR ^a R ^b , PR ^a or S, wherein R ^a , R ^b and R ^c are each independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl; and

(iii) reacting said amine having general formula (VII) with hyaluronic acid having general formula (IX) to obtain the bioactive hyaluronic acid-based macromolecule:

In various embodiments, R ¹ , R ³ , L and Z ¹ contain one or more features and/or share one or more properties that are similar to those described above.

In various embodiments, R ³ and R ⁴ are each independently selected from H, C1-C20 alkyl, C2-C20 alkenyl or C2-C20 alkynyl, wherein at least one of R ³ and R ⁴ is H.

In various embodiments, step (ii) comprises the use of diamine R ⁴ R ³ N-L- R ¹ -NH2 for coupling hyaluronic acid to norbornene dicarboxylic anhydride. The diamine used may be one that is commercially available. Advantageously, the method is a straightforward reaction and does not require a polyethylene glycol) aminocarboxylic acid which is commercially unavailable and synthetically challenging to make. In various embodiments therefore, the method does not require tedious multi-step and/or low yielding synthesis procedures. In various embodiments, the diamine R ⁴ R ³ N-L-R ¹ -NH2 is used in slight excess to ensure that the amine having general formula (VII) does not become connected with norbornene dicarboximide on two ends, which would otherwise turn the diamine R ⁴ R ³ N-L-R ¹ -NH2 into a linker instead of a terminating group.

In various embodiments, the diamine is a heteroalkylene diamine, wherein L is heteroalkylene. In various embodiments, L is C20-C300 heteroalkylene or a heteroalkylene having from 20 carbon atoms to 300 carbon atoms. In various embodiments, L has a number average molecular weight of between about 500 and about 7,000. In various embodiments, the heteroatom in L is O. In various embodiments, L is polyalkylene glycol. In various embodiments, the diamine is a polyethylene glycol) diamine, wherein L is polyethylene glycol). In various embodiments, L is selected from the group consisting of PEG500, PEGeoo, PEG700, PEGsoo, PEG900, PEG1000, PEG1100, PEG1200, PEG1300, PEG1400, PEG1500, PEG2000, PEG2500, PEG3000, PEG3500, PEG4000, PEG4500, PEG5000, PEGeooo and mixtures thereof.

In various embodiments, the method further comprises, prior to step (iii), purifying the amine having general formula (VII) to isolate the product and/or remove impurities. In various embodiments, the step of purifying comprises washing with at least one of an acid or a base. The step of purifying may comprise washing with at least one of an acid or a base at least once, at least twice, at least thrice, at least four times, at least five times, at least six times, at least seven times or at least eight times to neutralise the amine having general formula (VII). In various embodiments, the step of purifying comprises double neutralisation steps. In one embodiment, the double neutralisation comprises a first step of washing with acid to remove unreacted diamine R ⁴ R ³ N-L-R ¹ -NH2 and a second step of washing with base to neutralise the amine having general formula (VII). It will be appreciated that as the diamine R ⁴ R ³ N-L-R ¹ -NH2 is basic, adding acid to said diamine will neutralise the diamine for removal from the amine having general formula (VII). It will also be appreciated that although the first step of washing with acid may protonate the amine having general formula (VII) at the amine terminal, the subsequent second step of washing with base or excess base converts the protonated form back into its free amine form. The acid used for the first neutralisation step may be selected from the group consisting of HCI, HNO3, H2SO4 and H3PO4. The base used for the second neutralisation step may be selected from the group consisting of NaOH, KOH, NH4OH and Ca(OH)2. In various embodiments, the second neutralisation step comprises washing with base at least once, at least twice, at least thrice or at least four times to fully extract the amine having general formula (VII) for maximised yield. In one embodiment, the second neutralisation comprises washing with base twice. Without being bound by theory, it is believed that up to 30% of the protonated form of amine having general formula (VII) may reside in the aqueous phase during extraction. In various embodiments therefore, the step of washing with base comprises washing the aqueous phase once with base and washing the organic phase once with base in order to completely extract the amine having general formula (VII) from both the aqueous and organic phases. Advantageously, by using double neutralisation steps after coupling to obtain the free amine terminus, the method eliminates the need for any additional steps such as protection/deprotection step(s). It will be appreciated by a person skilled in the art that the use of diamine, particularly poly(ethyleneglycol) diamine is extremely challenging and typically requires protection of one amine terminal in order to couple to a norbornene dicarboxylic acid anhydride. Indeed, in various embodiments, the polyalkylene glycol such as PEG are used as spacers, linkers or linking groups in the overall polymers, instead of as terminal groups. Thus, it may appear intuitive to consider protecting one amine terminal of a PEG diamine to couple it with norbornene dicarboxylic acid anhydride. The protecting group may then be removed to expose the amine terminus for further reactions. However, this would add extra steps to the reaction and hence may not be desirable. Embodiments of the present disclosure has managed to overcome this problem in the synthesis and purification steps by carrying out double neutralization steps after coupling to obtain the free amine terminus for further coupling to hyaluronic acid. In various embodiments, the amine has the formula (Vll-a):

(Vll-a)

Material Comprising Hyaluronic Acid-based Synthetic Copolymer

There is also provided a material comprising a copolymer as disclosed herein for use in medicine. The material may also be a material that is suitable for use in stimulating/promoting skin, bone and/or cartilage tissue regeneration, wound healing and/or wound treatment. The material may also be a material that is suitable for use in controlling and/or reducing inflammation. Accordingly, in various embodiments, the material is a regenerative material that is suitable for connective tissue regeneration such as skin, bone and/or cartilage tissue regeneration.

In various embodiments, the material is part of or used on an apparatus selected from the group consisting of wound dressing, skin scaffold, skin substitute, dermal template, dermal matrix, cartilage scaffold, bone scaffold, organoid scaffolds, dermal fillers, implants (e.g., cartilage implant, spinal fusion implant, meniscal implant, bone implant), medical devices, aesthetic, cosmetic and consumer care products. For example, the material may be a scaffold for skin and/or tissue regeneration comprising the bioactive hyaluronic acid-based synthetic copolymer disclosed herein. The material may be a material suitable for increasing biocompatibility of polyamide used in medical devices. The material may be a polylactide scaffold suitable for stimulating skin and/or tissue regeneration. The material may be a poly(lactic-co-glycolic acid) scaffold suitable for stimulating skin and cartilage tissue regeneration. The material may also a poly(methyl methacrylate) material for use in medical implants.

In various embodiments, the material comprises a hyaluronic acid-based synthetic copolymer that is represented by general formula (VIII): wherein p > 1 ; q > 1 ; x > 1 ; y > 1 ; R ² is selected from a single bond, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxyalkyl, optionally substituted alkylcarbonyl or optionally substituted alkylcarbonylalkyl; R ³ is selected from H, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl; and

Y ¹ comprises a synthetic polymer derived from polycarprolactone (PCL), polylactic acid (PLA), polyl(lactic-co-glycolic acid) (PLGA), polystyrene (PS), poly(methyl methacrylate) (PMMA), polyamide (PA) or polyacrylate.

In various embodiments, the material comprises a hyaluronic acid-based synthetic copolymer that is represented by general formula (Vlll-a):

(Vlll-a)

In various embodiments, p is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36,

37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54, 55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75, 76, 77, 78,

79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96, 97, 98, 99,

100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 1 10, 1 11 , 1 12, 113, 1 14, 115,

1 16, 1 17, 1 18, 1 19, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 ,

132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147, 148, 149 or 150. In various embodiments, q is 1 , 2, 3, 4, 5, 6,7,8,9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,

34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54,

55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75,

76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96,

97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111 , 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149 or 150. In various embodiments, x is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20. In various embodiments, y is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,

27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47,

48, 49, 50, 51 , 52, 53, 54, 55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68,

69, 70, 71 , 72, 73, 74, 75, 76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89,

90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123,

124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139,

140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155,

156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171,

172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187,

188, 189, 190, 191 , 192, 193, 194, 195, 196, 197, 198, 199 or 200.

In various embodiments, wherein Y ¹ is selected from the following general formulae (lll-a), (lll-b), (lll-c), (lll-d), (lll-e), (lll-f) or (lll-g) :

(Ilka) (lll-b) (lll-c) wherein

R ⁶ is optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted 5-membered or 6-membered cyclic ring (e.g., aromatic or heteroaromatic);

R ⁷ is H or CH ₃ ; m > 1 ; and n > 1.

In various embodiments, n is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36,

37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54, 55, 56, 57,

58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75, 76, 77, 78,

79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96, 97, 98, 99,

100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 110, 111 , 112, 113, 114, 115,

116, 117, 118, 119, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 ,

132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147,

148, 149 or 150. In various embodiments, m is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12,

13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54,

55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75,

76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96,

97, 98, 99, 100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 1 10, 1 11 , 1 12, 1 13,

1 14, 1 15, 1 16, 1 17, 1 18, 119, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 , 132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147, 148, 149 or 150.

In various embodiments, the following structure of general formula (X) contained in general formula (VIII) has a weight average molecular weight (Mw) of from about 1 ,000 to about 8,000. For example, the structure may have a weight average molecular weight of from about 1 ,000 to about 8,000, from about 1 ,100 to about 7,900, from about 1 ,200 to about 7,800, from about 1 ,300 to about 7,700, from about 1 ,400 to about 7,600, from about 1 ,500 to about 7,500, from about 1 ,600 to about 7,400, from about 1 ,700 to about 7,300, from about 1 ,800 to about 7,200, from about 1 ,900 to about 7,100, from about 2,000 to about 7,000, from about 2,100 to about 6,800, from about 2,200 to about 6,600, from about 2,300 to about 6,400, from about 2,400 to about 6,200, from about 2,500 to about 6,000, from about 2,600 to about 5,800, from about 2,700 to about 5,600, from about 2,800 to about 5,400, from about 2,900 to about 5,200, from about 3,000 to about 5,000, from about 3,050 to about 4,950, from about 3,100 to about 4,900, from about 3,150 to about 4,850, from about 3,200 to about 4,800, from about 3,250 to about 4,750, from about 3,300 to about 4,700, from about 3,350 to about 4,650, from about 3,400 to about 4,600, from about 3,450 to about 4,550, from about 3,500 to about 4,500, from about 3,550 to about 4,450, from about 3,600 to about 4,400, from about 3,650 to about 4,350, from about 3,700 to about 4,300, from about 3,750 to about 4,250, from about 3,800 to about 4,200, from about 3,850 to about 4,150, from about 3,900 to about 4,100, from about 3,950 to about 4,050, or about 4,000. The structure represented by general formula (X) may have a weight average molecular weight of from about 1 ,168 - 7,616.

In various embodiments, the polyethylene glycol (PEG) contained in general formula (VIII) has a weight average molecular weight of from about 1 ,000 to about 8,000, about 1 ,100, about 1 ,200, about 1 ,300, about 1 ,400, about 1 ,500, about 1 ,600, about 1 ,700, about 1 ,800, about 1 ,900, about 2,000, about 2,100, about 2,200, about 2,300, about 2,400, about 2,500, about 2,600, about 2,700, about 2,800, about 2,900, about 3,000, about 3,100, about 3,200, about 3,300, about 3,400, about 3,500, about 3,600, about 3,700, about 3,800, about 3,900, about 4,000, about 4,100, about 4,200, about 4,300, about 4,400, about 4,500, about 4,600, about 4,700, about 4,800, about 4,900, about 5,000, about 5,100, about 5,200, about 5,300, about 5,400, about 5,500, about 5,600, about 5,700, about 5,800, about 5,900, about 6,000, about 6,100, about 6,200, about 6,300, about 6,400, about 6,500, about 6,600, about 6,700, about 6,800, about 6,900, about 7,000, about 7,100, about 7,200, about 7,300, about 7,400, about 7,500, about 7,600, about 7,700, about 7,800, about 7,900, or about 8,000.

In various embodiments, the polyethylene glycol (PEG) is represented by general formula (XI):

In various embodiments, y is 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 , 32, 33, 34, 35, 36, 37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 , 52, 53, 54, 55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 , 72, 73, 74, 75, 76, 77, 78, 79, 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 , 92, 93, 94, 95, 96, 97, 98, 99, 100, 101 , 102, 103, 104, 105, 106, 107, 108, 109, 1 10, 1 11 , 1 12, 113, 1 14, 115, 1 16, 1 17, 1 18, 1 19, 120, 121 , 122, 123, 124, 125, 126, 127, 128, 129, 130, 131 , 132, 133, 134, 135, 136, 137, 138, 139, 140, 141 , 142, 143, 144, 145, 146, 147, 148, 149, 150, 151 , 152, 153, 154, 155, 156, 157, 158, 159, 160, 161 , 162, 163, 164, 165, 166, 167, 168, 169, 170, 171 , 172, 173, 174, 175, 176, 177, 178, 179, 180, 181 , 182, 183, 184, 185, 186, 187, 188, 189, 190, 191 , 192, 193, 194, 195, 196, 197, 198, 199 or 200.

In various embodiments, the material may further comprise the hyaluronic acid-based synthetic copolymer blended with one or more synthetic base polymers.

In various embodiments, there is also provided a material for use in medicine, the material comprising:

(i) a base synthetic polymer (e.g., PCL, PLA, PLGA, PS, PMMA and PA); and

(ii) a bioactive hyaluronic acid-based synthetic copolymer.

In various embodiments, the one or more synthetic base polymers is selected from the group consisting of polycarprolactone (PCL), polylactic acid (PLA), polyl(lactic-co-glycolic acid) (PLGA), polystyrene (PS), poly(methyl methacrylate) (PMMA), polyamide (PA), polyacrylate and combinations thereof. In various embodiments, the one or more synthetic base polymers may correspond to the synthetic polymer of Y ¹ of general formula (VIII).

In various embodiments, the material is in the form of a formulation suitable for electrospinning, melt extrusion, hot melt extrusion, injection moulding, compression molding, fused filament fabrication, fused deposition modelling, additive manufacturing, melt blowing, 3D printing or the like. In various embodiments, the material is in the form of a formulation suitable for preparation into suspension in gels, creams, balms or the like. In various embodiments, the material is in the form of a formulation suitable for forming a coating, layer or the like. In various embodiments, such methods of manufacturing are used for preparation of aesthetic, beauty, cosmetics and/or consumer care products.

In various embodiments, the material is processed/printed/three- dimensionally printed via electrospinning, melt extrusion, hot melt extrusion, injection moulding, fused filament fabrication, fused deposition modelling, additive manufacturing, melt blowing, 3D printing and the like.

In various embodiments, the material or bioactive hyaluronic acid-based synthetic copolymer is compatible with biological systems or parts of the biological systems without substantially or significantly eliciting an adverse physiological response such as a toxic reaction/response, an immune reaction/response, an injury or the like when used on/in the human or animal body. In various embodiments, the polymer is substantially devoid of materials that elicit an adverse physiological response.

There is also provided a method of accelerating/stimulating/promoting cell growth, skin and/or cartilage and/or bone tissue regeneration, wound healing, or inflammation control and/or reduction, the method comprising administering/applying the bioactive hyaluronic acid-based synthetic copolymer or material disclosed herein to a subject (e.g. human or animal or body part) in need thereof.

There is also provided use of the bioactive hyaluronic acid-based synthetic copolymer or material disclosed herein in the manufacture of a medicament for accelerating/stimulating/promoting cell growth, or skin and/or cartilage and/or bone tissue regeneration, wound healing, or inflammation control and/or reduction. In various embodiments, there is provided a medical device comprising the regenerative material disclosed herein. The regenerative material may be one that has been electrospun, melt extruded, injection molded, compression molded and/or 3D printed.

BRIEF DESCRIPTION OF FIGURES

FIG. 1 is a schematic diagram 100 of a hyaluronic acid-based norbornene macromonomer in accordance with various embodiments disclosed herein.

FIG. 2 is a schematic diagram 200 of a hyaluronic acid-based synthetic brush polymer in accordance with various embodiments disclosed herein.

FIG. 3 shows the thermogravimetric analysis (TGA) graphs of (1 ) pure hyaluronic acid; (2) NB-PEG macromonomer containing pegylated hyaluronic acid (NB-PEG3400HA); (3) macromonomer containing norbornenyl group and PCL (NB-PCL); (4) copolymer obtained from ROMP of NBPEG3400HA and NB-PCL (PCL-co-PEGHA ROMP copolymer); and (4) NBPEG3400 macromonomer in accordance with various embodiments disclosed herein. “HA” refers to (1 ) pure hyaluronic acid; “NB-PEG3.4K-HA” refers to NB-PEG macromonomer containing pegylated hyaluronic acid (NB-PEG3400HA); “NB-PCL” refers to (3) macromonomer containing norbornenyl group and PCL; “PCL-PEGHA” refers to (4) copolymer obtained from ROMP of NBPEG3400HA and NB-PCL (PCL-co-PEGHA ROMP copolymer); and “NB-PEG3.4K” refers to NBPEG3400 macromonomer.

FIG. 4 shows the alkaline phosphatase (ALP) activity in C2C12s cultured on 3D printed PLA scaffolds. C2C12 cells were seeded on 3D printed PLA scaffolds. Scaffolds were untreated with BMP-2. Total protein was extracted after 72 h and ALP activity was determined using p-Nitrophenyl phosphate (p-NPP). The synthetic polymers PLA-MPEG and PLA-HA were blended with commercial PLA as base material at 10 wt%. PLA-MPEG 10% refers to PLA-MPEG blended with 10 wt% of base material (i.e. commercial PLA); and PLA-PEGHA 10% refers to PLA-PEGHA blended with 10 wt% of base material (i.e. commercial PLA). MPEG represents methoxy PEG that does not contain biomolecules. PLA-MPEG was used as control.

FIG. 5 shows photographs of porcine wound bed captured on Days 3, 7, 14 and 21.

FIG. 6 shows representative photomicrographs of stained H&E porcine tissue sections on Days 7 and 14. Scale bar = 100 pm.

EXAMPLES

Example embodiments of the disclosure will be better understood and readily apparent to one of ordinary skill in the art from the following examples, tables and if applicable, in conjunction with the figures. It should be appreciated that other modifications related to structural, and chemical changes may be made without deviating from the scope of the invention. Example embodiments are not necessarily mutually exclusive as some may be combined with one or more embodiments to form new example embodiments. The example embodiments should not be construed as limiting the scope of the disclosure.

Example 1 : Method of Preparing Bioactive Hyaluronic Acid-Based Synthetic Copolymer

The method of preparing a bioactive hyaluronic acid-based synthetic copolymer in accordance with various embodiments disclosed herein involve creating macromonomers of the bioactive hyaluronic acid (HA) molecules and macromonomers of the synthetic polymers separately and using ring opening metathesis polymerization (ROMP) techniques to link these otherwise mutually incompatible molecules together. The result is a brush polymer bearing both the bioactive hyaluronic acid (HA) molecule and the synthetic polymer for overall mechanical strength of the material (Scheme 1 ).

In the following examples, brush polymers containing pendant arms of synthetic polymers and bioactive hyaluronic acid (HA) molecules tethered on polyethylene glycol (PEG) moieties, have been created. Synthetic polymers may include poly(caprolactone) (PCL), polyesters such as poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA), polystyrene (PS), polyacrylates, poly(meth)acrylates such as poly(methyl methacrylate) (PMMA) and polyamides (PA).

The resultant polymer shows bioactivity of the hyaluronic acid (HA) biomolecule involved while having much better physical and mechanical properties for good material handling and processability.

The polymers can be subsequently blended with polymers similar to that on the pendant arms to create bioactive materials for use in biomedical devices such as wound dressings, tissue scaffolds, plastic surgery implants, prosthetic parts, cartilage joint implants etc.

The synthetic route for preparing a bioactive hyaluronic acid-based synthetic polymer in accordance with various embodiments disclosed herein is illustrated in Scheme 1.

= group containing synthetic poiymer (e.g. PCI, PLA. PLGA, PS, PMMA, PA) or parts thereof group containing pegylated hyaluronic acid (HA) or derivatives thereof

Scheme 1. Brush polymer synthesis by ROMP to create bioactive hyaluronic acid-based synthetic polymers The following examples show the synthesis of a series of brush copolymers containing pegylated hyaluronic acid (HA) with synthetic biocompatible polymers via ring opening metathesis polymerization (ROMP). These brush copolymers can be utilized as bioadditives in scaffolds for skin, bone and/or cartilage tissue regeneration.

Synthetic polymers that may be selected for the synthetic polymer side chains on the brush polymers include poly(caprolactone) (PCL), polyesters such as poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA), polyamide (PA), polystyrene (PS) and polyacrylates.The exact polymer to be selected is dependent on the nature of the biomedical device, aesthetic, beauty or consumer care product to be manufactured, for example whether properties such as biodegradability, flexibility, impact-resistance etc, are required in the device material. The method involves creating macromonomers of HA and synthetic polymers separately, and using ring opening metathesis polymerization (ROMP) techniques to prepare copolymers. The result is a brush polymer bearing both HA and the synthetic polymer with better thermal stability and biocompatibility for scaffold materials use in skin, bone and cartilage tissue regeneration.

Key technical features of the copolymer disclosed herein include bioactivity, thermal stability for melt extrusion-based material processing and biodegradability.

Macromonomers containing HA molecules are copolymerized with synthetic biocompatible polymers (PCL, PLA, PLGA, polyamide (PA), polyacrylate and polymethyl methacrylate (PMMA)) to form brush type copolymer. This copolymer structure provides better solubility of HA molecules in organic solvents for material processing using methods such as electrospinning or formulation and enhances the thermal stability of HA for melt extrusion and 3D printing. The HA based copolymers may also be further blended with base polymers such as PCL, PLA, PLGA, PA, polyacrylate or PMMA, for skin scaffold, dermal matrix, dermal template, dermal filler, skin substitute, bone scaffold, cartilage implant fabrication, aesthetic, beauty and consumer care product formulation. This ensures that the HA molecules are localized on the implant or application site and do not induce undesirable effects in other parts of the body, therefore providing better control of biocompatibility, bioactivity, biodegradability, and mechanical stability.

Example 2: Bioactive HA-Based Macromonomers and Method of Synthesis

To develop new skin, bone and cartilage tissue regenerative materials using hyaluronic acid (HA) as biomolecule, HA biomacromonomers are first prepared as described below. By connecting HA to norbornene linkers via polyethylene glycol (PEG) units, a library of HA biomacromonomers is created that can be used to form various types of polymers for different types of tissue regenerative materials.

NBPEG-NH2 is first synthesized as described in Scheme 2.1. The HA containing biomacromonomer is synthesized by amine coupling reaction between NBPEG-NH2 and HA (Scheme 2.2).

A general strategy for the synthesis of bioactive HA-based macromonomers in accordance with various embodiments disclosed herein has been developed. Polyethylene glycol diamine of various chain lengths (e.g., Mw = 1 ,000 - 6,000) are reacted with c/s-norbornene-exo-2,3-dicarboxylic anhydride to create the main macromonomer body, i.e. macromonomer body containing norbornene dicarboximide and polyethylene glycol (NBPEG-NH2) (Scheme 2.1 ). n = 21, 76, 135

(PEG 1,000, 3,400, 6,000)

Scheme 2.1 . Synthesis of NBPEG-NH2 macromonomer body using PEG diamine of various chain lengths

Once NBPEG-NH2 is created, hyaluronic acid (HA) is then reacted with these NBPEG-NH2 chains to create the bioactive HA-based macromonomer with the desired therapeutic properties (Scheme 2.2).

Scheme 2.2. Synthesis of NBPEG macromonomer containing hyaluronic acid (NBPEGHA)

FIG. 1 shows a HA-based macromonomer 100 designed in accordance with various embodiments disclosed herein. The HA-based macromonomer 100 comprises a norbornenyl (e.g., norbornene dicarboximide) group 102 which serves/acts as ROMP site and a hyaluronic acid (HA) 106 which are linked via a biocompatible polymer linker (e.g., PEG) 104. HA based norbornene macromonomer for copolymerization with other synthetic polymers (e.g. PCL, PLA, PLGA, PS, PMMA and PA)

=> Norbornenyl group to create brush type polymer structure by ring opening metathesis polymerization (ROMP)

=> PEG to enhance the hydrophilicity and extend the chain length of HA to ensure “visibility” to cells

=> HA for retaining water molecules, fibroblast/keratinocytes cell and chondrocyte cell binding

=> Synthetic polymer arms help improve thermal stability of material for material processing

Example 3: Synthetic Macromonomers and Method of Synthesis

Schemes 3.1 to 3.5 show synthetic macromonomers of PCL, PLA, PLGA, PS, PMMA and PA.

PLA, PLGA, PCL are created using ring opening polymerization on a norbornene dicarboximide linker with a terminal hydroxy group. Briefly, cis- norbornene-exo-2,3-dicarboxylic anhydride is reacted with 3-amino-1 -propanol to create an initiator molecule. This initiator is then reacted with s-caprolactone (or D, L-lactide for PLA formation; D, L-lactide and glycolide for PLGA formation) in the presence of Sn(Oct)2 catalyst to form PCL chains on the norbornene dicarboximide linker, N-[3-hydroxylpropyl]-c/s-5-norbornene-exo-2,3- dicarboximide (NPH), to give the PCL macromonomer (NB-PCL) (Scheme 3.1 ) (or NB-PLA macromonomer).

Scheme 3.1. Synthesis of PCL macromonomer

PLA macromonomer is synthesized using ring-opening polymerization. C/s-norbornene-exo-2,3-dicarboxylic anhydride is first reacted with 3-amino-1 - propanol to provide the initiator molecule. This alcohol initiator is then stirred with D, L-lactide in the presence of Sn(0ct)2 catalyst to provide NB-PLA macromonomer (Scheme 3.2).

Scheme 3.2. Synthesis of PLA macromonomer

Poly(lactic-co-glycolic acid) (PLGA) macromonomer is synthesized in 2 steps via a c/s-norbornene-exo-2,3-dicarboximide aminopropanol initiator molecule (Scheme 3.3).

Scheme 3.3. Poly(lactic-co-glycolic acid), PLGA macromonomer synthesis

Scheme 3.4. Synthesis of PS macromonomer (c) via norbornene dicarboximide linker (a) and PS-azide (b). PMMA macromonomer (d) synthesized by directly growing from a norbornenyl-functionalized ATRP initiator.

PS is prepared by atom transfer radical polymerization (ATRP) where an azide terminal is formed at the polymer chain end after the polymerization reaction so that the norbornene dicarboximide linker can be “clicked” onto the polymer to create PS (NB-PS) macromonomer (Schemes 3.4a to 3.4c).

PMMA (NB-PMMA) macromonomer is prepared using atom transfer radical polymerization (ATRP). A/-(Hydroxypropyl)-c/s-5-norbornene-exo-2,3- dicarboximide (NPH) is first reacted with 2-bromoisobutyryl bromide to provide the norbornenyl-functionalized ATRP initiator. NB-PMMA macromonomer is then synthesized by directly growing the polymer from a norbornenyl-functionalized ATRP initiator using CuBr/TMEDA catalytic system (Scheme 3.4d).

Polyamide (PA) macromonomers can be created by ring opening polymerisation of a-caprolactam on A/-(carboxypentyl)-c/s-5-norbornene-exo-2,3- dicarboximide (NCP) under reflux conditions using H2O and H3PO3 as catalysts (Scheme 3.5). NCP served as the initiator for a-caprolactam ROP.

Scheme 3.5. PA macromonomer synthesized via norbornene dicarboximide linker and s-caprolactam Example 4: Ring Opening Metathesis Polymerisation Catalysts

The final bioactive brush type copolymer is prepared by ROMP of synthetic macromonomer (e.g., PCL, PLA, PLGA, PS, PMMA or PA) with NBPEG macromonomer containing hyaluronic acid (NBPEGHA) using Grubbs type catalysts 1 or 2 (Scheme 4).

Scheme 4. Examples of Grubbs type catalyst for ROMP reactions

Example 5: Bioactive HA-Based Synthetic Copolymers Examples

HA-based synthetic brush type copolymer is synthesized via copolymerization of NBPEG macromonomer containing hyaluronic acid (NBPEGHA) with NB macromonomer containing synthetic polymer using ROMP.

FIG. 2 shows a bioactive HA-based synthetic copolymer 200 designed in accordance with various embodiments disclosed herein. The bioactive HA-based synthetic brush type copolymer 200 comprises a poly(norbornene dicarboximide) backbone 202, pendant arms of synthetic polymers 204a, 204b and 204c, and pendant arms of bioactive HA molecules 206a, 206b and 206c tethered on PEG chains 208a, 208b and 208c. As shown in the schematic diagram, the pendant arms are attached to the poly(norbornene dicarboximide) backbone 202. 206a, 206b and 206c may be the same or different types/lengths of bioactive moieties (i.e. hyaluronic acid and/or derivatives thereof).

Examples of synthetic polymers include poly(caprolactone) (PCL), polyesters such as poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA), polystyrene (PS), polyacrylates, poly(meth)acrylates such as poly(methyl methacrylate) (PMMA) and polyamides (PA).

Depending on the targeted application, the bioactive HA-based macromonomer can be matched with different types of synthetic polymers to create materials with different physical properties.

It will be appreciated that the presence of hyaluronic acid (HA) in the copolymer imparts biocompatibility to the polymer and can directly affect the proliferation and migration of fibroblast, keratinocyte and chondrocyte cell, which makes it useful for skin, bone and cartilage tissue regeneration. On the other hand, the presence of the synthetic polymer imparts the attributes such as thermal stability and mechanical strength to the copolymer.

A series of bioactive HA-based synthetic copolymers that bear synthetic polymers such as polystyrene, polyacrylate, poly(meth)acrylate, poly(lactide), poly(lactic-co-glycolic acid), poly(£-caprolactone) and polyamide with pegylated hyaluronic acid as side chains on a poly(norbornene dicarboximide) backbone have been developed, via ring opening metathesis polymerization (ROMP).

Scheme 5.1 shows an example of a bioactive HA-based synthetic copolymer synthesized using polycaprolactone (PCL).

Scheme 5.2 shows an example of a bioactive HA-based synthetic copolymer synthesized using polylactide (PLA). Scheme 5.3 shows an example of a bioactive HA-based synthetic copolymer synthesized using poly(lactic-co-glycolic acid) (PLGA).

Scheme 5.4 shows an example of a bioactive HA-based synthetic copolymer synthesized using poly(methyl methacrylate) (PMMA).

Scheme 5.1. Ring opening metathesis polymerization (ROMP) to obtain bioactive synthetic polymer containing both hyaluronic acid (HA) and polycaprolactone (PCL) where [Ru] refers to Grubbs’ catalyst.

Scheme 5.2. Ring opening metathesis polymerization (ROMP) to obtain bioactive synthetic polymer containing both hyaluronic acid (HA) and polylactide (PLA) where [Ru] refers to Grubbs’ catalyst.

Scheme 5.3. Ring opening metathesis polymerization (ROMP) to obtain bioactive synthetic polymer containing both hyaluronic acid (HA) and poly(lactic-co-glycolic acid) (PLGA) where [Ru] refers to Grubbs’ catalyst.

Scheme 5.4. Ring opening metathesis polymerization (ROMP) to obtain bioactive synthetic polymer containing both hyaluronic acid (HA) and poly(methyl methacrylate) (PMMA) where [Ru] refers to Grubbs’ catalyst.

Example 6: Thermal Stability, Bioactivity and Applications in Scaffolds

6.1. Thermal Stability

Thermal stability of macromonomers and their copolymers were evaluated by DTA-TGA (NETSCH STA 449) (FIG. 3) The TGA results showed multiple weight loss steps for HA. The first region is characteristic for water loss of approx. 10 wt% up to 180 °C. The second and third regions are characteristic of a two- stage polysaccharide degradation, at 180 °C and 300 °C, corresponding to weight loss of about 40 wt% and 10 wt%, respectively. NBPEGHA macromonomer exhibited two main weight loss region. The first region showed weight loss of approx. 5 wt% up to 180 °C and is associated primarily with the loss of water from HA. The second weight loss of approx. 28 wt% from 180 °C to 300 °C, shows improvement in thermal stability of HA after coupling with NBPEG. TGA result of copolymers showed that major weight losses occurred in the temperature ranges of (220 - 420)°C for PCL-co-PEGHA. The HA based copolymers behave in a similar fashion to their synthetic macromonomer such as PCL. The improvement/enhancement in thermal stability of the materials allows for material processing by melt extrusion techniques (e.g., melt extrusion of the HA based copolymers).

The enhanced thermal stability of HA is achieved in the form of the HA macromonomer and also in the form of the brush copolymer of HA with synthetic polymer. The enhanced thermal stability allows for the melt extrusion of HA based copolymers to be carried out. In addition, the brush copolymer of HA exhibits bioactivity which facilities skin, bone and cartilage tissue regeneration.

6.2. Bioactivity

Alkaline phosphatase (ALP) is the most widely recognized biochemical marker for osteoblast activity. The osteoinductivity of the BMP-2 can be measured in vitro using a pluripotent myoblast C2C12 cell line. ALP assays using C2C12 myoblast cells and BMP-2, were performed on 3D-printed sheet samples of PLA, PLA-MPEG copolymer and PLA-HA copolymers (FIG. 4). The synthetic polymers, PLA- MPEG and PLA-HA, were blended with commercial PLA as base material at concentration of 10% and 3D printed into sheets.

The ALP assay results show the ability of PLA-HA to promote osteogenic activity of cells compared to pure PLA.

To evaluate the wound healing efficacy and skin regeneration properties of the PLGA-HA scaffolds, in vivo porcine partial thickness burn wound model was used. PLGA-HA was blended with commercial PLGA at 10 wt% and 3D printed into porous dermal scaffolds. Partial thickness burn wounds of 5 x 5 cm ² were created on the flank of each animal, using a metal brand immersed in a 95 °C hot water bath. PLGA-HA samples, negative control (tulle gras dressing) and positive control of Biobrane (gold standard for second degree partial thickness burns), were randomly distributed on each of the wounds for each pig. Wound healing was then monitored over a period of 21 days and photographs were taken (FIG. 5). For the negative control group, wound healing was slow, and inflammation was observed even on Day 21 , with significant amount of slough still present. On the other hand, complete healing with negligible inflammation on Day 21 was observed for treatment group PLGA-HA 10%. Some slight inflammation characterized by skin redness was still visible in the wound treated with Biobrane (positive control) on Day 21. Skin biopsies were taken on Day 7 and Day 14, and tissues were sectioned, fixed, stained with hematoxylin and eosin (H&E), and evaluated for re-epithelization and inflammation (FIG. 6). On Day 7, PLGA-HA 10% showed healthy epidermis growth that was attached to the dermis, while there was no epidermis regeneration for negative control and minimal epidermis growth for positive control. On Day 14, epidermis growth was observed in all treatment groups. No additional inflammation was observed in wounds treated with PLGA-HA compared to negative and positive controls. The porcine wound healing study showed that 3D printed PLGA-HA dermal scaffolds can encourage healing and skin regeneration in partial thickness burn wounds, and the healing outcomes were superior compared to gold standard, Biobrane.

6.3. Applications

The present disclosure provides a new synthesis method to create bioactive HA-based macromonomer and bioactive HA-based synthetic copolymer by undergoing copolymerization with synthetic polymer via ROMP.

In various embodiments, hyaluronic acid (HA) bound on polymers are able to bind fibroblast, keratinocytes cell and chondrocyte cell while staying immobilized on scaffold instead of leaching to other parts of body for undesirable side effects or being metabolized prematurely. Advantageously, in various embodiments, hyaluronic acid (HA) shows improved thermal stability on binding to polymer, allowing for material processing. For example, the polymer is 3D- printable by fused filament fabrication, fused deposition modelling and/or customized into a scaffold. Embodiments of the bioactive HA-based synthetic polymer disclosed herein allow for hyaluronic acid (HA) to be blended into base material of synthetic polymer similar to the synthetic polymer side arms of the copolymer, without phase separation. In various embodiments, the bioactive copolymers may be blended with synthetic base polymers such as PCL, PLA or PLGA to create scaffolds.

In various embodiments, bioactive HA-based macromonomers may be easily copolymerized with another synthetic copolymer to form bioactive HA- based synthetic copolymers with desired physical and mechanical properties. Advantageously, there is increased stability of HA upon connection to polymer linker. For example, embodiments of the bioactive HA-based synthetic copolymers show enhanced thermal stability, allowing for melt extrusion and material processing. Embodiments of the strategy disclosed herein allow for HA molecule to be used in polymer synthesis without loss of bioactivity.

Embodiments of the method disclosed herein allow HA-based macromonomers to be paired with synthetic polymer of choice to create bioactive HA-based synthetic polymer that has both mechanical and physical properties of synthetic polymer and biological activity of bioactive molecule. Advantageously, both hydrophobic (synthetic polymer chain) and hydrophilic (pegylated HA chain) in the brush polymer structure provide better blending/formulation in organic solvent/aqueous medium.

Embodiments of the method disclosed herein is an easy strategy to create different types of bioactive HA-based polymers that are chemically bonded instead of physical blends of bioactive HA molecules into synthetic polymers.

Embodiments of the bioactive HA-based synthetic copolymers disclosed herein may be used as bioactive materials for medical devices. For example, embodiments of the bioactive HA-based synthetic polymer may be used to create materials for use in skin scaffold, dermal matrix, dermal template, skin substitute, dermal filler, bone scaffold, cartilage scaffold, wound dressing, cartilage implants, bone implants, spinal fusion implants and/or meniscal implants, aesthetic, beauty and consumer care products. Embodiments of the bioactive HA-based synthetic polymer may also be used as additives for skin or bone scaffold to create stimulus required for skin or bone tissue regeneration.

Example 7: Experimental Methods

7.1. General procedure for Examples 7.2 to 7.5

HA biomacromonomer and PCL synthetic macromonomer synthesis, ring opening metathesis polymerization (ROMP) reactions, were carried out under nitrogen atmosphere. NPH-PLA and NPH-PLGA synthetic macromonomers were carried out under vacuum condition in a fume hood. NBPEG and NPH syntheses were carried out in a fume hood under atmospheric conditions. Synthesis steps for NBPEG and NPH are described in Examples 7.9 and 7.19. All solvents used in the glovebox are anhydrous and used as purchased. Hyaluronic acid (HA) with average Mw 3,000 - 5,000 was purchased from Glentham Life Sciences Ltd. PEG diamine (Mw 1 ,000 and 3,400) and c/s-norbornene-exo-2,3-dicarboxylic anhydride were purchased from Alfa Aesar. Grubbs second generation catalyst, hydroxybenzotriazole (HOBt), 1 -ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N,N-diisopropylethylamine ('Pr2EtN) were purchased from Sigma Aldrich. All purchased reagents were used as received.

¹ H NMR spectra were recorded on a JEOL 500 MHz NMR spectrometer using deuterium oxide as solvent for HA based macromonomer. Chloroform-d was used as solvent for PCL, PLA and PLGA macromonomer and their copolymers. Gel permeation chromatography (GPC) was carried out on a Waters Aquity APC System equipped with Acquity APC XT 45, XT 200 and XT 450 columns, Acquity Rl detector. THF was used in sample preparation and a flow rate of 0.5 ml/min at 40 °C was used. Thermogravimetric analysis (TGA) was performed using a TGA (NETSCH STA 449) from room temperature to 700 °C with a heating rate of 10 °C/min in an argon atmosphere.

7.2. Synthesis of HA macromonomer (NB-PEGHA)

Hyaluronic acid (HA) (100 mg, 0.025 mmol) was dissolved in deionized (DI) water at pH 5.0-5.5 (10 mL, pH adjusted by 0.1 M HCI), and EDC (3.88 mg, 0.025 mmol) and NHS (2.87mg, 0.025 mmol) were added into HA solution and stirred for 1 hr. NBPEG3400NH2 (88.8 mg, 0.025 mmol) was added to the reaction mixture and stirred at room temperature overnight and the reaction was stopped by adding 1 M NaOH the final pH was adjusted to 7-8. The solution was dialyzed against DI water for 48 h using 5,000 Da molecular weight cut off cellulose membrane to remove uncoupled NBPEG3400NH2 and HA. A pale yellow powder was obtained after the freeze-drying process. ¹ H NMR (500MHz, D ₂ O): 5 6.37 (t, 2H), 3.64 (s, 4H, PEG), 2.01 (s, 3H,

HA).

7.3. Synthesis of HA based PCL brush copolymer by ROMP (PCL-r-PEGHA)

NBPEG3400-HA (0.1 eq) was weighed into a 4 ml glass vial followed by addition of NPHPCL (50 mg, 0.0125 mmol). THF (0.05 M wrt. NPHPCL) was added and the mixture was stirred at room temperature until a clear solution is obtained. A solution of catalyst 3 in THF (1 .25 mol %, 0.05 M) was added to the solution and the mixture was stirred for 2 hr at room temperature before the reaction was terminated by adding ethyl vinyl ether. The polymer solution was precipitated in methanol. The polymer mixture was centrifuged and supernatant was decanted. The residue was repeatedly washed with DI water to remove unreacted NBPEG3400-HA and followed by washing with methanol before drying under vacuum at 45 °C overnight.

¹ H NMR (500MHz, CDCh): 5 4.05 (m, 2H, PCL), 3.64 (s, 4H, PEG), 2.30 (t, 2H, PCL), 1 .50-1 .7 (m, 4H, PCL), 1 .25-1 .45 (, 2H, PCL). GPC analysis (THF): Mn = 60,057 PDI = 1.33

7.4. Synthesis of HA based PLA brush copolymer by ROMP (PLA-r-PEGHA)

NBPEG3400-HA (0.1 eq) was weighed into a 4 ml glass vial followed by addition of NPHPLA (50 mg, 0.007 mmol). THF (0.05 M wrt. NPHPLA) was added and the mixture was stirred at room temperature until a clear solution is obtained. A solution of catalyst 3 in THF (1.25 mol %, 0.05 M) was added to the solution and the mixture was stirred for 2 hr at room temperature before the reaction was terminated by adding ethyl vinyl ether. The polymer solution was precipitated in cold methanol. The polymer mixture was centrifuged and supernatant was decanted. The residue was repeatedly washed with DI water to remove unreacted NBPEG3400-HA and followed by washing with cold methanol before drying under vacuum at 45 °C overnight.

¹ H NMR (500MHz, CDCh): 5 5.27-5.08 (m, PLA), 3.64 (s, PEG), 1 .97-1 .47 (m, PLA).

7.5. Synthesis of HA based PLGA brush copolymer by ROMP (PLGA-r-PEGHA)

NBPEG3400-HA (0.1 eq) was weighed into a 4 ml glass vial followed by addition of NPHPLGA (50 mg, 0.007 mmol). THF (0.05 M wrt. NPHPLGA) was added and the mixture was stirred at room temperature until a clear solution is obtained. A solution of catalyst 3 in THF (1 .25 mol %, 0.05 M) was added to the solution and the mixture was stirred for 2 hr at room temperature before the reaction was terminated by adding ethyl vinyl ether. The polymer solution was precipitated in cold methanol. The polymer mixture was centrifuged and supernatant was decanted. The residue was repeatedly washed with DI water to remove unreacted NBPEG3400-HA and followed by washing with cold methanol before drying under vacuum at 45 °C overnight.

¹ H NMR (500MHz, CDCh): 5 5.21 (m, 1 H, LA), 4.82 (m, 2H, PGA), 3.64 (s, 4H, PEG), 1 .57 (d, 3H, PLA).

7.6. Synthesis of HA based PMMA brush copolymer by ROMP (PMMA-r-PEGHA)

NBPEG3400-HA (0.1 eq) was weighed into a 4 ml glass vial followed by addition of NBPMMA (50 mg, 0.0093 mmol). THF (0.02 M wrt. NBPMMA) was added and the mixture was stirred at room temperature until a clear solution was obtained. A solution of catalyst 3 in THF (1 .25 mol %, 0.02 M) was added to the solution and the mixture was stirred for 2 hr at room temperature before the reaction was terminated by adding ethyl vinyl ether. The polymer solution was precipitated in cold methanol. The polymer mixture was centrifuged, and supernatant was decanted. The residue was repeatedly washed with DI water to remove unreacted NBPEG3400-HA and followed by washing with cold methanol before drying under vacuum at 45 °C overnight.

¹ H NMR (500MHz, CDCh): 5 ¹ H NMR (500MHz, CDCI3): 5 3.64 - 3.59 (m, PMMA and PEG), 2.00 - 1 .70 (m, PMMA), 1.11 - 0.73 (m, PMMA).

7.7. General procedure for Examples 7.8 to 7.19

Ring opening metathesis polymerization (ROMP) reactions, PS (NB-PS) and PCL (NPH-PCL), macromonomer synthesis, and catalyst 2 synthesis were carried out in a Vacuum Atmosphere glovebox under nitrogen atmosphere. NBPEG and NB amino alcohol condensation reactions to obtain N- (Hydroxypropyl)-c/s-5-norbornene-exo-2,3-dicarboximide (NPH), N- (carboxypentyl)-c/s-5-norbornene-exo-2,3-dicarboximide (NCP) and N- (Hydroxydecanyl)-c/s-5-norbornene-exo-2,3-dicarboximide (NDH), were carried out in a fumehood under atmospheric conditions. All solvents used in the glovebox are anhydrous and used as purchased. Grubbs second generation catalyst (catalyst 1) was purchased from Sigma Aldrich and peptides were purchased from Biomatik Inc. PEG diamine was purchased from Alfa Aesar (1 ,000 and 3,400) or Sigma Aldrich (6,000). HOBT, HBTU, 'Pr ₂ EtN were purchased from Sigma Aldrich and c/s-norbornene-exo-2,3-dicarboxylic anhydride was purchased from Alfa Aesar.

¹ H NMR spectra were recorded on a JEOL 500 MHz NMR spectrometer using MeOD as solvent for all biomolecule-based macromonomers. CDCh is used as solvent for PCL macromonomer. Gel Permeation Chromatography was carried out on a Waters Aquity APC System equipped with Acquity APC XT 45, XT 200 and XT 450 columns, Acquity Rl detector. THF was used in sample preparation and a flow rate of 1 .0 ml/min at 40 °C was used. Polystyrene was used as calibration standard. TGA/DSC is measured using TA Instruments SDT2960 simultaneous DSC-TGA.

7.8. Synthesis of (H2lMes)(pyr)2(CI)2RuCHPh (Catalyst 2)

Pyridine (2 mL) was added to catalyst 1 (0.5 g, 0.59 mmol) in a 20 mL vial with a screw cap. The reaction was stirred at room temperature for 15 min during which a colour change from red to green was observed. Hexanes (16 mL) was added to the green solution and a green solid began to precipitate. The green precipitate was vacuum-filtered, washed with hexanes (4 x 10 mL), and dried under vacuum to afford catalyst 2 as a green powder.

7.9. Synthesis of N-(Hydroxypropyl)-cis-5-norbornene-exo-2,3- dicarboximide (NPH)

A round-bottom flask was charged with c/s-5-norbornene-exo-2,3- dicarboxylic anhydride (0.985 g, 6.0 mmol) and 3-amino-1 -propanol (0.473 g, 6.3 mmol). To the flask was added 30 mL toluene, followed by triethylamine (84 pL, 0.60 mmol). A Dean-Stark trap was attached to the flask, and the reaction mixture was heated at reflux (135 ^S C) for 4 h. The reaction mixture was then cooled and concentrated in vacuo to yield a pale yellow oil. This residue was diluted with 30 mL of dichloromethane and washed with 0.2 M HCI (20 mL) and sat. NaCI (20 mL). The organic layer was dried over Na2SO4, concentrated in vacuo and dried overnight in a vacuum oven to yield 1.22 g of white solid. ¹ H NMR (500 MHz, CDCh): 5 6.27 (t, J = 2.0 Hz, 2H), 3.64 (t, J = 6.4 Hz, 2H), 3.53 (q, J = 6.1 Hz, 2H), 3.26 (s, 2H), 2.71 (m, 2H), 2.60 (m, 1 H), 1.84-1.70 (m, 2H), 1.55 (m, 1 H), 1.24 (d, 1 H).

7.10. Synthesis of NPH-PCL macromonomer by ROP

NPH-PCL macromonomers with different degree of polymerization (DP) were prepared by ROP. As an example, s-CL (0.5 ml, 0.52 mol) was added to a 20 ml scintillation vial containing NPH initiator (0.05 g, 0.23 mmol), dissolved in toluene (1 ml). Sn(Oct)2 (0.0037g, 9.1 gmol) was added to the mixture and the resultant solution was stirred at 110 °C for 90 min and precipitated into methanol. The methanolic solution was then placed in the freezer overnight to result in white precipitate which was filtered and washed with methanol. The residue is then dried under vacuum overnight. GPC analysis (THF): M _n = 5,613, PDI = 1 .08, yield 0.4478 g.

A standard solution of Sn(Oct)2 of concentration 91 pmol/ml, was prepared and used for ROP reactions.

7.11. Synthesis of NPH-PLA macromonomer by ROP

NPH-PLA macromonomers with different degrees of polymerization (DP) were prepared by ROP. As an example, a flame-dried 25 mL Schlenk tube was charged with NPH initiator (1 10 mg, 0.50 mmol), D, L-lactide (864 mg, 6.0 mmol), Sn(Oct)2 (2 mg), and a stir bar. The tube was evacuated and backfilled with nitrogen four times, and was then immersed in an oil bath at 130 °C. After 2.5 h, the contents were cooled to room temperature, diluted with dichloromethane, and precipitated into cold methanol twice. The macromonomer was isolated by decanting the supernatant and dried under vacuum overnight. GPC analysis (THF): M _n = 2,471 , PDI = 1 .20, yield 0.600 g. ¹ H NMR (CDCh): 5 6.28 (br t, 2H), 5.27-5.08 (m), 4.35 (m, 1 H), 4.19 - 4.02 (m, 2H), 3.62 - 3.44 (m, 2H), 3.27 (s, 2H), 2.69 (m,2H), 1.97-1.47 (m), 1.19 (d, 1 H).

7.12. Synthesis of N-(Hydroxydecanyl)-cis-5-norbornene-exo-2,3- dicarboximide (NDH)

A round-bottom flask was charged with c/s-5-norbornene-exo-2,3- dicarboxylic anhydride (0.95 g, 5.8 mmol) and 10-amino-1 -decanol (1.0 g, 5.8 mmol). To the flask was added 20 mL of toluene, followed by triethylamine (80 pL, 0.58 mmol). A homogeneous solution was obtained upon heating. A Dean-Stark trap was attached to the flask, and the reaction mixture was heated at reflux (135 °C) for 4 h. The reaction mixture was then cooled and concentrated in vacuo to yield an off-white solid. This residue was dissolved in 20 mL of CH2CI2 and washed with 0.1 N HCI (10 mL) and sat. NaCI (10 mL). The organic layer was dried over MgSCU and concentrated in vacuo to yield 1 .96 g of colorless, viscous oil. ¹ H NMR (500 MHz, CDCh): 5 1 .20-1 .28 (m, 13H), 1 .49-1 .56 (m, 5H), 2.65 (d, J = 1 .5 Hz, 2H), 3.26 (t, J = 1 .5 Hz, 2H), 3.44 (t, J = 7.5 Hz, 2H), 3.62 (t, J = 6.5 Hz, 2H), 6.27 (t, J = 2.0 Hz, 2H).

7.13. Synthesis of N-(Pentynoyldecanyl)-cis-5-norbornene-exo-2,3- dicarboximide

To a round-bottom flask were added A/-(hydroxydecanyl)-c/s-5- norbornene-exo-2,3-dicarboximide (NDH) (0.80 g, 2.5 mmol), A/-(3- dimethylaminopropyl)-/V-ethylcarbodiimide hydrochloride (EDC) (0.58 g, 3.0 mmol), and 4-dimethylaminopyridine (DMAP) (0.10 g, 0.82 mmol), followed by 10 mL of CH2CI2. Pentynoic acid (0.25 g, 2.5 mmol) was added as a solution in 5 mL of CH2CI2 via syringe. The reaction mixture was allowed to stir at room temperature overnight. The reaction mixture was washed with water (2x 20 mL) and sat. NaCI (20 mL) and dried over MgSCU. The solvent was evaporated, and the remaining residual was purified by silica gel chromatography (ethyl acetate/hexanes, 1 :9 v/v) to give 0.88 g product as a colorless oil (88% yield). ¹ H NMR (500 MHz, CDCh): 5 1.21 -1.33 (m, 13H), 1.49-1.54 (m, 3H), 1.62 (t, J = 7.5 Hz, 2H), 1.97 (t, J = 2.5 Hz, 1 H), 2.48-2.57 (m, 4H), 2.67 (d, J= 1.5 Hz, 2H), 3.27 (t, J = 1 .5 Hz, 2H), 3.45 (t, J = 7.5 Hz, 2H), 4.09 (t, J = 7 Hz, 2H), 6.28 (t, J = 2.0 Hz, 2H).

7.14. Synthesis of NB-PS macromonomer by A TRP-click

NB-PS macromonomers with different degree of polymerization (DP) were prepared using ATRP, click-reactions. As an example, CuBr (0.1435 g, 1 mmol) was weighed into a 20 ml scintillation vial in the glovebox. Styrene (pre-filtered through basic AI2O3, 1 1.5 ml, 100 mmol) was added followed by methyl-2- bromopropionate (1 12 pl, 1 mmol) and PMDETA (209 pl, 1 mmol). The mixture was heated at 80 °C for 1 h and added dropwise to stirring MeOH (400 ml) to give a white precipitate (ppt) in deep blue solution. The ppt was filtered to obtain a blueish white solid that is redissolved in minimal CH2CI2, reprecipitated in MeOH and filtered. This redissolving, precipitation and filtration process is repeated until a pure white solid of PS-Br is obtained. The solid is then dried in a vacuum oven overnight. GPC analysis (THF): M _n = 2,523, PDI = 1.18.

PS-Br (0.5 mmol) and NaNs (2.5 mmol) were added to a 20 ml scintillation vial in the glovebox, followed by DMF (10 ml) and the mixture was stirred for 48 h to result in a colourless solution with white precipitate of NaBr. The mixture was added to a beaker of stirring MeOH in the fumehood. The white precipitate was filtered, washed with MeOH and dried in a vacuum oven to give PS-N3 prepolymer.

In a 20 ml scintillation vial was added PS-N3 prepolymer (0.1 mmol) and A/-(Pentynoyldecanyl)-c/s-5-norbornene-exo-2,3-dicarboximide (0.15 mmol) and CuBr (0.01 mmol). THF (2 ml) and PMDETA (0.01 mmol) were added and the mixture stirred at 50 °C overnight. MeOH was added to the cooled reaction mixture to yield a white ppt which was filtered and washed with MeOH, followed by drying in a vacuum oven, to yield NB-PS macromonomer. ¹ H NMR (CDCh): 7.10 - 6.46 (m), 6.28 (s, 2H), 5.04 - 4.94 (m, 1 H), 4.13 - 4.0 (m, 2H), 3.51 - 3.40 (m, 5H), 3.27 (s, 2H), 2.91 - 2.86 (m, 2H), 2.67 - 2.56 (m, 2H), 0.92 (br s, 3H).

7.15. Synthesis of norbornenyl-functionalized A TRP initiator

A round-bottom flask was charged with A/-(Hydroxypropyl)-c/s-5- norbornene-exo-2,3-dicarboximide (NPH) (0.66 g, 3.0 mmol). To the flask was added dichloromethane (12 mL), followed by triethylamine (0.63 mL, 4.5 mmol). The reaction flask was submerged in an ice-water bath and 2-bromoisobutyryl bromide (0.55 mL, 4.5 mmol) was added dropwise to the reaction mixture. When the addition was completed, the reaction mixture was allowed to stir at room temperature overnight. The reaction mixture was washed with 0.1 M HCI (15 mL), saturated NaHCOa solution (15 mL) and sat. NaCI (2 x 15 mL). The organic layer was dried over NaaSC and concentrated in vacuo. The residue was purified by silica gel chromatography (dichloromethane) to yield the product as a pale yellow solid (0.80 g, 72 %). ¹ H NMR (500 MHz, CDCh): 5 6.28 (t, J = 1.8 Hz, 2H), 4.17 (t, J = 6.5 Hz, 2H), 3.61 (t, J= 7.1 Hz, 2H), 3.28 (s, 2H), 2.69 (d, J = 1 .8 Hz, 2H), 1.99-1.96 (m, 8H), 1.52 (m, 1 H), 1.21 (d, J = 9.9 Hz, 1 H).

7.16. Synthesis of NB-PMMA macromonomer by A TRP

NB-PMMA macromonomers with different degrees of polymerization (DP) were prepared using ATRP. As an example, a 25 mL Schlenk tube was charged with norbornenyl-functionalized ATRP initiator (53 mg, 0.143 mmol), MMA (1.06 mL, 10.0 mmol), anisole (1.0 mL) and TMEDA (0.01 1 mL, 0.072 mmol). The solution was degassed by three freeze-pump-thaw cycles. During the final cycle, the Schlenk tube was filled with nitrogen, and CuBr (10.3 mg, 0.072 mmol) was quickly added to the frozen reaction mixture. The Schlenk tube was sealed, evacuated, and backfilled with nitrogen three times. The Schlenk tube was thawed to room temperature and the polymerization was conducted in a 70 °C oil bath for 3 h. The mixture was filtered through neutral alumina, precipitated into MeOH and filtered. The solid is then dried in a vacuum oven overnight. GPC analysis (THF): M _n = 5,158, PDI = 1 .13. ¹ H NMR (CDCh): 56.30 (s, 2H), 4.17 (m, 2H), 3.76 (m), 3.65-3.59 (m), 3.28 (s, 2H), 2.72 (s, 2H), 2.00 - 1 .69 (m), 1 .07 - 0.75 (m).

7.17. Synthesis of N-(Carboxypentyl)-cis-5-norbornene-exo-2,3- dicarboximide (NCP) c/s-5-norbornene-exo-2,3-dicarboxylic anhydride (4.0 g, 24.3 mmol) and 6-aminohexanoic acid (3.3 g, 25.3 mmol) were weighed into a round-bottom flask. To the solid mixture was added toluene (50 mL) and EtaN (410 pL, 2.92 mmol). The flask was fitted with a Dean-Stark trap and heated to reflux for 4h. The mixture was then allowed to cool to room temperature and diluted with CH2CI2 (50 mL) and washed with 1 M aqueous HCI (2 x 20 mL). The organic layer was washed with saturated aqueous NaCI (20 mL), dried with Na2SC , filtered, and concentrated under reduced pressure to provide NCP as a pale yellow solid. ¹ H NMR (500 MHz, CD3OD, 25 °C) 5 6.26 (t, 2H, J= 2.0 Hz), 3.44 (m, 2H), 3.25 (m, 2H), 2.66 (d, 2H, J= 1 .0 Hz), 2.32 (t, 2H, J= 7.2 Hz), 1 .63 (m, 2H), 1 .55 (m, 2H), 1.46-1.51 (m, 1 H), 1.33 (m, 2H), 1.19 (d, 1 H).

7.18. Synthesis of NCP-PA 6 macromonomer by ROP

NCP-PA 6 macromonomers with different degree of polymerization (DP) were prepared by ROP. As an example, s-caprolactam (2.56g, 12 mmol) was weighed into a 50 ml round bottom flask (rbf) containing NCP initiator (0.2 g, 0.6 mmol) with nitrogen inlet. Deionized H2O (5 ml) with H3PO3 (0.081 g) were added to the mixture and the resultant mixture was heated at 170 °C for 30 min and maintained at 240 °C for 4hrs. H2O was removed by distillation and the reaction was heated at 240 °C under vacuum for another 2hrs. Beige solid was precipitated from MeOH and washed repeatedly by it. NCP-PA 6 was obtained upon drying in a vacuum oven overnight. ¹ H NMR [500 MHz, DCO2D/ CD2CI2 (1 :4),]: 5 6.42 (br, PA 6), 6.28 (s, 2H, NCP), 3.42 (s, 6H, NCP), 3.14-3.12 (m, PA 6), 2.67 (s, 2H, NCP), 2.14-2.12 (m, PA 6), 1.56-1.53 (m, PA 6), 1.46-1.44 (m, PA 6), 1.29-1.25 (m, PA 6).

7.19. Synthesis of NBPEG macromonomer body (for H2N-PEG-NH2 1000, 3,400 and 6000)

PEG diamine (1 g) and c/s-norbornene-exo-2,3-dicarboxylic anhydride (1 eq.) were added to a 100 ml rbf, followed by toluene (50 ml). T riethylamine (1 eq.) was added and the mixture stirred under reflux overnight, with a dean stark trap attached for water removal. The resulting solution was evaporated to dryness and dichloromethane (40 ml) was added, followed by 0.1 M HCI (40 ml). The organic layer was extracted and washed with 0.1 M NaOH (50 ml). 0.1 M NaOH (50 ml) was added to the aqueous fraction from the acid wash followed by CH2CI2 (30 ml). The organic layer was extracted and combined, washed with sat. NaCI before drying over Na2SC . The material was evaporated to dryness to give a pale orange oil, NBPEG for PEG diamine 1 ,000 and beige solid for PEG diamine 3,400 and 6,000. ¹ H NMR (MeOD): 5 = 6.36 (t, 2H, NB), 3.67 (s, PEG), 3.21 (s, 2H, NB), 2.74 (s, 2H, NB), 1 .92 (s, 2H).

It will be appreciated by a person skilled in the art that other variations and/or modifications may be made to the embodiments disclosed herein without departing from the spirit or scope of the disclosure as broadly described. For example, in the description herein, features of different exemplary embodiments may be mixed, combined, interchanged, incorporated, adopted, modified, included etc. or the like across different exemplary embodiments. The present embodiments are, therefore, to be considered in all respects to be illustrative and not restrictive.