A OPARTICLES AND CONTROLLED FORMATION METHOD

PRIORITY CLAIM AND REFERENCE TO RELATED APPLICATION

[001 ] The application claims priority under 35 U.S.C. § 119 and from ail applicable statutes and treaties from prior provisional application serial number 61/895,100 which was filed October 24, 2013.

FIELD

[002] A field of the invention is nano materials. The present invention concerns polymeric nanoparticles, formation methods, and application. Example applications include imaging, diagnostics and drug delivery.

BACKGROUND

[003] Polymeric nanoparticles of biodegradable and biocompatible polymers are of interest for various applications, and are of particular interest for controlled drug delivery and drug targeting. A variety of techniques have been researched for forming the polymeric nanoparticles and for functionalizing the nanoparticles to carry payloads such as drugs. Example formation techniques for creating drug delivery polymeric nanoparticles include bulk mixing, high pressure homogenization, nanoprecipitation and double emulsion. Kumaresh S. Soppimath , Tejraj M. Aminabhavi , Anandrao R. ulkarni , Waiter E. Rudzinsk, "Biodegradable polymeric nanoparticles as drug deliver}' devices," journal of Controlled Release, Volume 70, Issues 1-2, Pages 1 -20, (2001 ).

[004] Nano precipitation and double emulsion techniques emulsify an organic solvent with the polymer in oil in water (O/W) to obtain polymeric nanoparticulate compounds. Modifications of the basic processes are obtained via solvent effects, concentration effects, high pressure homogenization, and similar variations. The common synthetic procedure remains as an oil in water or water in oil emulsificatioii process. Problems arise due to the toxicity caused due to the presence of residual organic solvents and residual monomers. Catarina Pinto Reis, Ronald J. Neufeld, Antonio J. Ribeiro, Francisco Veiga, "Natioencapsulation I. Methods for preparation of drug-loaded polymeric nanoparticles," Nanomedicine: Nanotechnology, Biology and Medicine, Volume 2, Issue 1 , Pages 8-21 [005] Synthesis of PMMA (poly(methyl methacrylate)) nanoparticles using MMA (methyl methacrylate) monomer through an em.ulsi.fi cation process has also been reported. A.N. Mendes, I. Hubber, M. Siqueira, G.M. Barbosa, D.L. Moreira, C. Holandino, J.C. Pinto , M. Nele, "Preparation and Cytotoxicity of Poly (M ethyl Methacrylate) Nanoparticles for Drug Encapsulation," Macromolecular Symposia, 319, 34-40 (2012). A significant limitation of this approach is toxicity due to the presence of MMA monomers and residual organic solvents, which leads to low drug encapsulation efficiency. The emulsion techniques also produce undesirably higher sized (larger than lOOnm) polydispersed particles. In addition, the particles produced by these techniques have a strong tendency toward aggregation. Some reported efforts to address these problems limit the polymer concentration to 0.1 % weight of polymer/volume of solvent. However, decreasing polymer concentration leads to additional challenges with respect to drug encapsulation.

[006] Drag delivery systems (DDS) should remain in systemic circulation for a predetermined period of time, generally tens of hours, for effective delivery of encapsulated compounds. Systemically administered DDS nanoparticles should remain in circulation for a longer time to increase their accumulation in targeted tissues before being cleared by the reticuloendothelial system, and be effectively internalized within the targeted cells. The accumulation can be influenced significantly by the physicochemical characteristics of nanoparticles, such as particle size, surface properties, and particle shape. Particles or molecules substantially larger than about 300nm and polvdisperse particles tend to ineffectively and insufficiently internalize within vasculatures. See, Yuan, Fan; Dellian, Marc; Fukumura, Dai; Leunig, Michael; Berk, David A,; Torchilin, Vladimir P.; Jain, Rakesh ., Cancer Research,, "Vascular permeability in a human tumor xenograft: molecular size dependence and cutoff size," 55 (17), 3752-6 (1995). This defeats efficacy for systematic drug delivery for large particles as drug delivery.

[007] Other prior techniques produce PMMA nanoparticles through co-polymerization of

PEG with MMA prior to polymerization for forming nanoparticles. See, e.g. Jin Sook Kim and Ji Ho Youk, "Encapsulation of nanomaterials within intermediary layer cross- linked micelles using a photo-cross~ii.nki.ng agent," Macromolecular Research, vol. 17, issue 11, pp 926-30 (2009). This approach can result in the nanoparticles having PEG present on both surface as well as within the nanoparticles. This presence may lead to drawbacks such as i) huge variations in the drug release properties since PEG is highl soluble in water, ii) unprecedented degradation of the nanoparticies, and (iii) changes in the intrinsic physiochemical properties of PMMA and its analogues.

[008] Javorek published a review of more than 40 works concerning synthesis of particles using Eiectrohydrodynamic (EHD) processes. The processes only demonstrated producing particles of 300 urn or more. A. Jaworek, "Micro- and nanoparticle production by electrospraying," Powder Technology, Volume 176, Issue 1, Pages 18-

35 (2007).

SUMMARY OF THE INVENTION

[009] A method produces polymer nanoparticies. Polymer solution is sprayed through a nozzle toward a collector. An electric field is created at the nozzle, such as by a voltage is applied to the nozzle to create the electric field. The voltage applied to the nozzle is from - l O(Kilovolt) to ~30(Kilovolt), distance from nozzle tip to collector is from - 1 (centimeter) to ~10 (centimeter) and the polymer concentration from -0.01 % to -0.5% w/w. Preferably a grounded liquid collectors is used. The invention provides biocompatible monodisperse polymer nanoparticies having a size of less than ~300nm, preferably less than -150nm. Payloads can be associated, and maintain efficacy, including more than one payload such as therapeutic agents and diagnostic agents on the same particles. Preferred particles are poly(methyl methacrylate) (PMMA-COOH) or acrylate analogues.

LIST OF ACRONYMS

[0010] DDS drug delivery system

[0011] EHD eiectrohydrodynamic

[0012] ICG indocyanine green

[0013] MMA methyl methacrylate

[0014] PEG polyethylene glycol

[0015] PMMA po lyimethyi methacrylate) . BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a schematic diagram that illustrates a preferred embodiment electrospray method for synthesis of PMMA-COOH nanoparticies (nanoparticies).

[0017] FIG. 2 is a schematic diagram of a preferred embodiment dual compound encapsulated nanoparticies;

[0018] FIG. 3 A is schematic diagram illustrating a preferred synthesis method for the surface functionalization of nanoparticies with PEG;

[0019] FIG. 3B is schematic diagram illustrating stage-wise a preferred process for surface functionalization;

[0020] FIGs. 4.A and 4B are TEM images of experimentally produced ICG encapsulated nanoparticies of th e invention;

[0021 ] FIG. 5 is a data graph of size distribution results (DLS results) of experimentally synthesized non-Pegylated and Pegylated nanoparticies with encapsulated ICG;

[0022] FIG. 6 is a data graph that shows UV-Vis spectroscopy of an ICG solution and ICG encapsulated nanoparticies solution of the invention that was produced in experiments;

[0023] FIG. 7 is a graph illustrating stability analysis of experimentally produced nanoparticies of the invention with respect to size based on DLS measurements; error bars represent the standard deviation from the average.

[0024] FIGs. 8A-8C are images of whole body imaging florescent imaging of mice using IV ! S imaging systems illustrating retention of experimentally produced nanoparticies;

[0025] FIG . 9 is a graph of data illustrating quantitative analyses detailing the normalized mean intensity for whole body imaging of mice with experimentally produced nanoparticies.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The present invention relates to the development of novel and stable polymeric nanoparticies for application in imaging, diagnostics and drug delivery systems. Preferred methods of the invention provide a composition controlled high field electrohydrodynamic formation method. The method can produce polymeric nanoparticies and nanoparticie drug delivery systems. The nanoparticies can be monodisperse and small, -300nm or less, and preferably ~150nm or less.

[0027] Preferred nanoparticies can cany more than one payload. Multiple compounds, such as multiple drugs, can be associated with preferred embodiment nanoparticies. [0028] A preferred controlled electrospray method of the invention can integrate multiple compounds into one polymeric matrix, wherein the desired intrinsic properties and integrity of the polymeric matrix of any given compound present in the matrix are not adversely affected by the presence of the polymeric matrix or the presence of any other encapsulated compound or group of compounds. These attributes give independent and associative properties to each individual component forming the nanoparticuiate system.

[0029] Preferred embodiments include surface flmctionaiized nanoparticies.

Embodiments provide carboxyl functionalized nanoparticies.

[0030] Particular preferred formation methods of the invention form poly (methyl methacrylate-co-methacrylic acid) (PMMA-co-MAA also called as PMMA-COOH) and its other acrylate analogues through a high field electrohydrodynamic method that provides control over nanoparticle size and provides monodisperse particles. Preferred embodiments provide PMMA-COOH nanoparticies that are monodisperse and ~300nm or less. Particular preferred embodiments are monodisperse and 150nm or less. Particular sizes can be selected by adjusting formation parameters and can be selected to depend upon the payioad(s) to be carried. More than one payload can be incorporated to form a drug delivery vehicle during the formation method.

[0031] In preferred methods of the invention, the voltage for the electro spray is from

~.l O(Kilovolt) to ~30(Kilovolt), the distance from tip to collector is from ~1 (centimeter) to -~10 (centimeter) and polymer concentration from -0.01% to ~0.5% w/ ^' w (±10%). In preferred embodiments, a liquid collector is used, and preferably grounded de-ionized water. Preferred embodiments of the invention provide highly uniform nanoparticies made up of PMMA-COOH and its analogues. The methods of the invention advantageously allow excellent control of particle size. Uniform mondisperse particles of small size provide reduced clearance from a patient by the reticuloendothelial system, and more effective internalization by targeted cells,

[0032] Other preferred embodiments include analogues of PMMA-COOH, that within the context of the present methods, include polymers that have a molecular weight at least and preferably greater than 5 kDa and preferably greater than 25kDa and sufficient viscoelasticity to transform into nanoparticies. Particular preferred analogues of PMMA-COOH include poly(ethyl acrylate), Poly(butylacrylate), poly(methyl acrylate), copolymers of neutral, alkaline and acidic ethyl acrylate and methyl acrylate polymers, Ammonio Methacrylate Copolymers, Aminoalkyl Methacrylate Copolymers, copolymers of vinyllactams such as poly(methyl methacrylate) PMMA, poly (2-hydroxyethyl methacrylate) PHEMA, and poly[N~(2- hydroxypropyljmethaerylamide. Preferably, the polymer is selected from poly(methyl methacrylate) PMMA-CQQH and its analogues.

Embodiments of the invention include mono disperse P MA-COOH nanoparticles having a diameter of -300 nm or less, and in particular preferred embodiments -150 nm or less. Carried payloads can affect the size. Embodiments of the invention include an electrospray method for forming mono disperse PMMA-COOH nanoparitlces. While not necessary to patentability, and without being bound to the theory, embodiments of the invention are believed to the inventors to provide a first method for simultaneous reduction of the size of a DDS nanoparticle while also providing for greater control and homogeneity of the DDS nanoparticle. This invention provides methods for the preparation of homogenous DDS Nanoparticles. Another advantage of methods of the invention is an ability to utilized preformed polymer and co-polymers allowing "on-demand" surface funetionalization based upon targeted application. Unlike prior techniques mentioned in the background, preferred electrospray methods of the invention can integrate multiple compounds into one polymeric matrix. Desired intrinsic properties and integrity of the polymeric matrix and a compound present in the matrix are not adversely affected by the presence of the polymeric matrix or the presence of any other encapsulated compound or gro u p of compounds. These attributes give independent and associative properties to each individual component forming the nanoparti c u late system .

A preferred electrospray method generates monodispersed droplets. The droplet size can vary from tens of nanometers to hundreds of micrometers, depending on the processing parameters. The preferred process generates structured nanoparticles in a controlled manner and can provide high drug/nucleic acid encapsulation efficiency. The preferred methods avoid toxicity problems that are inherent to emulsification methods. Particles of the invention can also be produced to have an affinity towards a specific cell or a surface modified to provide longer blood residence time. These features can provide enhanced permeability and retention, or cell specific targeting.

Preferred methods of the invention provide monodisperse nanoparticles of PMMA, PMMA-COOH or its analogues using preformed PMMA polymer or its analogues with relatively high encapsulation efficiency, drug loading efficiency and homogenous particle size distribution which has not been reported anywhere. Poly (methyl methacrylate-co-methacrylic acid) is a polymer made from co polymerization of Poly (methyl methacryiate) and meth acrylic acid. The specific purpose of using this methaerylic component within PMMA is to provide the polymeric system with surface functionality. In other words, PMMA in presence of -CQOH group are biocompatible as well as functionalizable through chemical conjugation.

[0039] Without being bound by the theory, embodiments of the invention are believed to provide a first method for encapsulation of multiple compounds within the PM MA nanoparticulate system for complementary functioning; for example, encapsulating a contrast agent as well as a therapeutic agent within each nanoparticle in the desired ratio to enable visualization along with therapy.

[0040] Experiments to demonstrate the invention have demonstrated the synthesis of nanoparticles of carboxyl functional ized PMMA nanoparticles using preformed Poly (methyl methacryiate -co-meth acrylic acid) polymer (PMMA-COOH).

[0041] Embodiments of the invention avoid problems such as associated with prior co- polymerization techniques discussed in the background that can lead to the intermittent formation of nanofibers along with the nanoparticles. Nanofibers are not desired for drug delivery applications. Nanoparticles of the invention can deliver payloads in vivo. Advantageously, preferred embodiment PMMA-COOH nanoparticles are biocompatible but are not biodegradable. In a diagnostic or therapeutic method of the invention, PMAA-COOH nanoparticles are delivered in vivo and allowed to collect in a quantity at a targeted location with an associated payload. Associated payloads can be encapsulated, embedded, attached, conjugated, or impregnated on or in the nanoparticle, or adsorbed at itssurface. in preferred methods of in vivo release, the payload is release in response to applied external energy, such as ultrasound or electromagnetic energy. In other preferred methods, the payload is released via enzymatic, protein or chemical reaction.

[0042] Molecule(s) or compound(s) can be associated as payloads without any chemical modification of the molecule or the compound for directly or indirectly assisting therapeutic or diagnostic effect. Molecules can be attached to the surface via covalent bonds, electrostatic bonds, or physically adsorption, including V an der Waal forces (conjugation).

[0043] Surface functionalization agents including zero-length crosslinkers, i.e. carbodiimides and its derivatives particularly EDC (carbodiimides), are engaged in this invention. They cause direct conjugation of carboxylates (-COOH) to primary amines (-NH2) without becoming part of the final crosslink (amide bond) between target molecules. Further, NHS ester i.e. N-Hydroxysuccinimide were utilized for further surface functio alization steps with reactive groups formed by EDC -activation of carboxylate molecules.

[0044] Preferred polymer nanoparticles can deliver associated therapeutic agents as payloads through systemic, oral, buccal, sublingual, ocular, topical, transdermal, nasal, pulmonoaryand _' Or rectal administration to a patient.

[0045] Preferred embodiment polymer nanoparticles can have single or multiple compounds associated as a payload. In preferred embodiments, single or multiple compounds are encapsulated or embedded within each nanoparticle. The integrity and properties of the compound and the nanoparticles are maintained during formation.

[0046] Preferred payloads can be bioaetive agents selected from a group that includes an antiproliferative agent, an anti-inflammatory agent, an antineoplastic, an antimitotic, an antiplatelet, an anticoagulant, an antifibrin, an antithrombin, a cytostatic agent, an antibiotic, an anti-allergic agent, an anti-enzymatic agent, an angiogenic agent, a cyto- protective agent, centra! nervous systems agents, antibacterials, a cardioprotective agent, and an antioxidant or any combination thereof.

[0047] Additional preferred payloads can be one or more active pharmaceutical ingredients embedded or encapsulated within the nanoparticles, and can also include also contrast agents.

[0048] Preferred nanoparticles include an active agent carried by the particle, such as a drug, a contrasting agent and combinations of same, embedded, conjugated, impregnated, or encapsulated in the nanoparticle, or adsorbed at the surface of the nanoparticle.

[0049] Preferred embodiments provide a method of preparing nanoparticles of Pegylated

PMMA-COOH and its analogues. The method includes activation of the earhoxyl group of PMMA-COOH and its analogues with Carbodiimides and NHS Esters, and chemical conjugation of PEG onto the surface of the nanoparticles through NH+-COO- linkage between PEG and the nanoparticles.

[0050] Preferred imaging methods of the invention include particle enhanced X-ray/Computed tomography (CT) or Magnetic Resonance Imaging (MPJ). Embodiments provide a method of diagnosis in a subject's body a target cell or target tissue. Nanoparticles of the invention include a contrast agent and are associated with one or more targeting agents effective to target delivery to a target ceil or target tissue. [0051] Preferred embodiment polymer nanoparticles are associated with multiple compounds and provide for complementary functioning. Complementary function can include, for example, a contrast agent as well as a therapeutic agent that can be associated with each nanopartieie in a predetermined desired ratio to provide both imaging enhancement and therapy.

[0052] Preferred polymer nanoparticles are both non biodegradable and biocompatible and have a surface sterical!y stabilized with hydrophilic molecules. Fabrication methods of the invention provide the ability for surface modifications, steric stabilization, surface functionalization, and general characteristic tailoring to improve performance of nanoparticles in delivering therapeutic agents and diagnostic agents.

[0053] Many active ingredients can be associated with preferred nanoparticles. An active ingredient is a substance that, when administered to an organism, has a biological effect on that organism is considered to be active ingredient. Preferred nanoparticles can be associated with both hydrophilic and hydrophobic active ingredients.

[0054] Preferred nanoparticles can be associated with one or more bioactive agents selected from a group that includes an antiplatelet, an anticoagulant, an anti fibrin, an antithrombin, a cytostatic agent, an antibiotic, an anti-allergic agent, an antiproliferative agent, an antiinflammatory agent, an antineoplastic, an antimitotic, an anti -enzymatic agent, an angiogenic agent, CNS drags and Antibactierais, Antifungals, Local anesthetics, a cyto-protective agent, a cardioprotective agent, and an antioxidant or any combination thereof.

[0055] Preferred nanoparticles can be associated with pharmaceutically-active agents which may be employed in the present invention includes but not limited to drugs used for Alzheimer's disease, anesthetics, acromegaly agents, analgesics, antiasthmatics, anticancer agents, anticoagulants and antithrombotic agents, anticonvulsants, antidiabetics, antiemetics, antiglaucoma, antihistamines, anti-infective agents, antiparkinsons, antiplatelet agents, antirheumatic agents, antispasmodics and anticholinergic agents, antitussives, carbonic anhydrase inhibitors, cardiovascular agents, cholinesterase inhibitors, treatment of CNS disorders, CNS stimulants, contraceptives, cystic fibrosis management, dopamine receptor agonists, endometriosis management, erectile dysfunction therapy, fertility agents, gastrointestinal agents, immunomodulators and immunosuppressives, memory enhancers, migraine preparations, muscle relaxants, nucleoside analogues, osteoporosis management, parasympathomimetics, prostaglandins, psychotherapeutic agents, sedatives, hypnotics and tranquilizers, drugs used for skin ailments, steroids and hormones.

[0056] Preferred nanoparticles can be associated with Antineoplastics, such as Alkylating agents such as Nitrogen mustards, Cyclophosphamide, Mechlorethamine or Mustine (HN2), Uramustine or Uracil Mustard, Melphalan, Eniluracil, Chlorambucil, Ifosfamide, Bendamustine, Nitrosoureas, Carmustine, L-phenylalanine mustard, Lomustine, Streptozocin, Alky! sulfonates such as Busulfan, Thiotepa, Procarbazine, Altretamiiie, Tetrazines (Dacarbazine, Mitozolomide, Temozolomide) and its analogues, Platinum-based chemotherapeutic drugs (termed platinum analogues) such as Picoplatin, Ormaplatin, Oxaplatin, Cisplatin, Carboplatin, Nedaplatin, Oxaliplatin, Satraplatin and Tripiatin Tetranitrate, Antimetabolites such as Purine, Pyrimidme analogues, Antifolates, Base analogues, Nucleoside Analogues, Antinutrient such as (Azathioprine and Mercaptopurine), 5- azadeoxycytosine, Thioguanine, Fludarabine, Pentostatin, Cladribine, Arabinosylcytosine, Capecitabine, Gemcitabine and Decitabine, Pemetrexed, Mecaptopurine, Thioguanine, Fludarabine phosphate, Fluorouracil, Floxuridine, Deoxycytidine, 5'~Deoxyfluro ridine, S-Azac^osi e, Cytarabine, Capecitabine, Gemcitabine, Pentostatin, Methotrexate, Azathioprine, Camphothecin derivatives such as Camptothecin, 10-hydiOX)'-7-ethylcamptothecin (SN38), 9- Aminocamptothecin, 10, 1 1 -methyl enedioxycamptothecin, Allopurinol, 2- chloroadenosine, Trimetrexate, 9-nitrocamptothecin, Amide derivatives such as Perfosfamide, Ifosphamide, Mefosphamide, Aminopterin derivatives such as Aminopteriri, Methylene- .10- Deazaaminopterin (MDAM), Epirubicin and karenitecm,

[0057] Preferred nanoparticles can be associated with Antineoplastic Antibiotics such as

Antinomycins derivatives such as Dactinomycin, Anthracyclines derivatives such as Daunorubicin, i3oxorubicin, Idarubicin, A^alrubicin, Aureolic acid derivatives such as Plicamycin, Mithramycin, Olivomycins, Chromomycins, variamycin, Bleomycin, Mithramycin, Mitomycin analogues such as Streptozocin, Acivicin, Calicheamicin, Plant products such as Vinka Alkaloids and their analogues such as Vincristine, Vinblastine, Vinrosidine, Vinleurosine, Vinglysinate, ⁷ indesme, a Diterpene derivative or a Taxane such as Paclitaxel (or its derivatives such as DHA-Paclitaxel or PG-Paxlitaxel) or Docetaxel, Other Miscellaneous compounds like Irinotecan, Etoposide, Teniposide, Vmorelbine, Asparaginase, Pegaspargase, Altretamine, Mitoxantrone hydrochloride, Adriamycin, Gallium Nitrate, Arsenic trioxide, Bexarotene, Sargramosiim, Filgrastim, Porfimer sodium, Mitotane, Leuprolide acetate, Triptoralen Pamoate, Gosereiin acetate, Anastrozole, Letrozole and Exemestane, Interferons like nterferon Alfa~2a, Interferon A lfa~2b, Interferon Alfa-n3, Aldesieukin, Demieukin diftitox, Bacillus Calmette-Guerm (BG), Monoclonal antibodies like Rituximab, Gemtuzumb, Ozogamicin, Radiotherapeutic agents such as Chromic Phosphate P32, Sodium Phosphate P32, Sodium Iodide ί 132, Strontium 89 Chloride, Samarium SM 153, Lexidronam, Cytoprotective agents such as MercaptoEthanesulfonic acid, Amifostine, Dexrazoxane, and Tromethamine, Amide derivatives such as Trifluoromethylaniline, Flutamide, Nilutamide, and Bicaiutamide, Progesterone and its analogues such as Medroxyprogesterone, and Megesterol Acetate,

[0058] Preferred nanoparticies can be associated with Anti-inflammatory Analgesics, which includes Salicylic acid derivatives such as Sodium salicylate, Salicylamide, Asprin, Salsalate, Diflunisai, Sodium Thiosalicylate, Magnesium Salicylate, Choline Salicylate, Ammonium, Lithium , and Strontium Salts of salicylic acid, N~ arylanthranilic acids derivatives including Mefenamic acid, Meclofenamate sodium, Aiylacetic acid derivatives such as Indometiiacin, Suiindac, Toimetin Sodium, Ibuprofen, Naproxen, Dexibuprofen, Fenoprofen, Ketoprofen, Etodolac, Arylpropionic acid derivatives Oxaprozin, Piroxicam, Meioxicam, Cox-2 inhibitors such as Celecoxib, Rofecoxib and Valdecoxib, Aniline and p-Amitiophenol derivatives such as Aniline, Acetanilid, P-Aminophenoi, Formanilid, Benzaniiid, Salicylaniiide, Exalgin, Acetaminophen, Anisidine, Phenetidine, Phenacetin, Lactyiphenetidin, Phenocoil, tyofine, p-Acetoxy acetanilide, Phenetsal, Pertonal, Pyrazolone and Pyrazolidmedione Derivatives including Antipyrme, Aminopyrine, Dipyrone, Phenylbutazone , Oxy henb utazone ,

[0059] Preferred nanoparticies can be associated with Antiviral agents, which includes

Nucleoside Antimetabolites such as Moxuridine, Trif!uridine, Vidarabine, Acyclovir, V alacyclovir, Ganciclovir, Famciclovir and Penciclovir, Cidofovir, Foscarnet sodium, Reverse Transcriptase Inhibitors such as Zidovudine, Didanosine, Zalcitabine, Stavudine, Lamivudine, Miceilaneous Nucleoside Antimetabolites like Rivavirin, Nonnucieoside Reverse Transcriptase inhibitors such as Nevirapine, Delavirdine, Efavirez, HIV protease inhibitors such as Saquinavir, Indinavir, Ritonavir, Amprenavir, and Nelfmavir.

[0060] Preferred nanoparticies can be associated with Antipsychotics, which includes

Plienotliiazines such as Promazine, Chlorpromazine hydrochloride, Triflupromazine Hydrochloride, Thioridazine Hydrochloride, Mesoridazine Besylate, Prochlorperazine Maleate, Perphenazine and Fluphenazine Hydrochloride, Ring analogues of Phenothiazines includes Thioxanthenes, Dibenzoxazepines, and Dibensodiazepines such as Thiothixene, Loxapine succinate and clozpine, Fiuoro butyrophenones such as Haloperidol, Droperidol, Risperidone, Pimozide, Penfluridol, β-Ammoketones such as Molindone hydrochloride, Benzamides includes emoxipride, Olanzapine and Quetiapine, Antimanic agents such as Lithium Salts such as Lithium carbonate, Lithium Citrate.

[0061 ] Preferred nanoparticles can be associated with Anticonvulsants or Antiepileptic Drags, such as Barbiturates such as Mephobarbital, Hydantoins includes Phenytoin, Mephenytoin and Ethotoin, Oxazolidinediones such as Trimethadione, Suceinimides includes Phensuximide, Methsuximide, Ethosuximide, Ureas and Monoacyl ureas includes Carbarn azepine, Miscellaneous agents like Valproic acid, Gabapentin, Tiagabine, Felbamate, Lamotrigme, Zonisamide, Topi.ram.ate (Toparnax), Benzodiazepines includes Clonazepam and Diazepam and Chloazepate etc.

[0062] Preferred nanoparticles can be associated with Antiarrhythmic agents, which includes such as Membrane Depressant Drugs such as Quinidine, Procainamide, Disopyramide, Lidocaine, Phenytoin sodium, Mexiietine, Toeainide, Flecainide Acetate, Moricizine, Propafenone, β-adrenergic Blocking agents such as Amiodarone, Bretylium Tosylate, Dofetilide, Ibutilide, Sotalol, Azimilide, Antiarrhythmics includes Verapamil, Diltiazem, Renin-Angiotensin system Inhibitors includes Lismopril, ACE inhibitor Prodrugs includes Enalaprii Maleate, Benazepril Hydrochloride, Quinapril Hydrochloride, Ramipril, Fosinopril sodium, Trandolapril, Angiotensin II blockers includes Losartan, Candesartan, Irbesartan, Valsartan, Adrenergic system Inhibitors includes Guanethidine derivatives such as Guanethidine Monosulfate, Guanadrel sulfate, Selective a-Adrenergic Antagonists includes Prazosin, Terazosin, Doxazosin, Centrally acting Adrenergic drugs includes Methyl dopate, Clonidine, Guanabenz acetate, Guanfacine hydrochloride, Vasodilating agents includes Hydralazine, Sodium Nitroprussi.de, Potassium Channel Agonists includes Diazoxide, Minoxidil, Positive Inotropic agents such as Digoxin, Digitalis, Amrinone, Milrinone, Antihyperiipidemic agents such as Clofibrate, Gemfibrozil, Fenofihrate, Dextrothyroxine sodium, Colesevelam, HMG-CoA Reductase inhibitors includes Lovastatin, Simvastatin, Pravastatin, Fluvstatin and Aton'astatin and Cerivastatm, Anticoagulants includes Protamine sulfate, Dicumaroi, Warfarin sodium, Anisindione, Hypoglycemic agents includes Sulfonylureas such as Tolbutamide, Chlorpropamide, Tolazamide, Acetohexamide, Glipizide, Glyburide, Glimepiride, Gliclazide, Nonsulfonyl ureas includes Repaglinide, Nateglinide, Thiazolindion.es includes Rosiglitazone, Pioglitazone, Bisguanidines includes Metformin, a-Glucosidase inhibitors includes Acarbose Miglitol, etc,

[0063] Preferred nanoparticles can be associated with Antibiotics, which includes β-Lactam

Antibiotics includes Penicillin G, Penicillin V, Nafciilin, Oxacillin, Cloxacillin, Dicloxacillin, Ampicillin, Amoxicillin, Cyclacillin, Carbenicillin, Ticarcillin, Piperacillin, Mezlocillin, Clavulanate Potassium USP, Sulbactam, Tazobactam, Carbapenems includes Thienamycin, Imipenem-Cilastatin, Meropenem, Biapenem, Cephalosporins includes Cephalexin, Cephradine, Cefadroxil, Cefachlor, Cefprozil, Loracarbef, Cefuroxime axetil, Cefixirne, Cephalothin, Cephapirin, Cefaz.ol.in, Cefamandole, Cefonicid, Ceforamide, Cefuroxime, Cefotaxime, Ceftizoxime, Ceftriaxone, Ceftazidime, Cefoperazone,, Cefoxitin, Cefotetan, Cefmetazole, Monobactams derivatives includes Stretomycin sulfate, Neomycin Sulfate, Paromomycin Sulfate, Kanamycin, Amikacin, Gentamicin sulfate, Netilmicin sulfate Sisomicin sulfate and Spectinomycin. Hydrochloride, Tetracyclines derivatives includes Tetracycline, Roiitetracyeiine, Oxytetracycline hydrochloride, Chlortetracycline Hydrochloride, Methacycline Hydrochloride, Demeclocycline USP, Meclocycline sulfosalicylate, Doxycycline and Minocycline, Macro lides derivatives includes Erythromycin, Erythromycin Stearate, Erythromycin Ethylsuccinate, Erythromycin Estolate, Erythromycin Gluceptate, Erythromycin Lactobionate, Clarithromycin, Azithromycin, Dirithromycin, Troleandomycin, Lincomycins derivatives includes Lincomycin, Clindamycin Hydrochloride, palmitate and Phosphate, Polypeptide derivatives includes Vancomycin Hydrochloride, Teicoplanin, Bacitracin, Polymyxin sulfate B, Colistin Sulfate, Colistimethate sodium, Gramicidin, Chloramphenicol, Novobiocin sodium, Mupirocin, Quinupristin/Dalfopristin, Linezolid and Fosfomycin Trometh amine.

[0064] Preferred nanoparticles can be associated with diagnostic agents, which includes

Technetium ( ^99m Tc), Fluorine ( ^{l S} F), Gallium ( ^/ Ga), Iodine Indium ( ^{l l f} In),

Oncoscint CR/OV, Thallium ( ²⁰¹ Τ') and Xenon Compounds ( ^Ll Xe

[0065] Preferred nanoparticles provide biocompatibility in all its states-i.e., in its intact state, its synthesized state, and in its decomposed state i.e., its degradation products— to perform its desired function with respect to a medical therapy, without eliciting undue undesirable local or systemic effects in the recipient or beneficiary of that therapy.

[0066] Preferred nanoparticles can be administered in vivo via systemic and nonsystemic delivery and/or administration of nanoparticles to a subject. Administration can include, but is not limited to, injection, intravenous, subcutaneous, intramuscular, and intra depot formulations, oral, buccal, sublingual, transdermal, topical, ocular, nasal, pulmonary, and rectal formulations.

[0067] Preferred particular in vivo payload release methods including internal release trigger mechanism like cleavage of nanoconstruct through enzymatic, protein or other chemical action within physiological conditions and external trigger methods including Highly Focused ultrasound (HIFU), laser assisted ablation, or any other externally applied energy to trigger the drug delivery and diagnostic deliver}' in vivo.

[0068] Preferred nanoparticles can be associated with pharmaceutical composition payloads that can optionally contain other non-essential ingredients. For example, the composition can contain up to 10 weight percent of conventional pharmaceutical adjuvants. These adjuvants or additives include preservatives, stabilizers, antioxidants, pH adjusting agents, and viscosity modifying agents.

[0069] Particular example experiments and embodiments will now be discussed. Artisans will recognize broader aspects of the invention from the description of the experiments.

[0070] EXPERIMENTS

[0071 ] The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

[0072] MATERIALS

[0073] Poly (methylmethacrylate-co-eth acrylic acid) (PMMA-COOH, Mw 34 Da), N-(3- dimethyiaminopropyi)~N'~ethylcarbodiimide hydrochloride (EDC), N~ hydroxysuccinimide (NHS), acetone, chloroform and indocyanine green (ICG) were obtained from Sigma-Aldrich (St. Louis, MO). Carboxyl-polyethylene glycol-amine terminated (cPEG-NH2, Mw 3 Da) was purchased from Laysan Bio Inc.(Arab, AL). All materials were used without any further purification.

Synthesis of PMMA-COOH nanoparticles

FIG. 1 illustrates the example preferred method. A polymer solution is prepared via normal techniques 10, suc as in a DCM methanol. An e!ectrohydrodynamic electrospray process 12 forms nanoparticles by driving the polymeric solution through a syringe pump at a constant flow rate. The present composition controlled high field eiectroiiydrodynamic process method drove the polymeric solution through a syringe pump at a constant flow rate. The solution ejected through the tip of an insulated stainless-steel nozzle (gauge 21 in the experiments). A high positive potential field 14 is applied at the nozzle. A sufficient field is created by applying, for example, ~10(Kilovolt) to ~30(Kilovolt) to the nozzle. Similar fields can be created by less direct techniques, but the voltage application is direct and convenient. A preferred collector 16 is grounded de-Ionized water. Using a liquid collector instead of a solid collector helps to avoid agglomeration of the particles due to the residual electrostatic forces present on the surface of the particles. Constant stirring of the collector is preferred to assists in producing a homogenous suspension of the nanoparticles. In an alternative process, the nanoparticles are collected onto a solid substrate and subsequently suspended the particles in aqueous media.

In the experiments, nanoparticles were electrosprayed using PMMA-COOH dissolved in Dichioromethane (DCM)/Methanol (Me) solvent. Different samples of nanoparticles included (1) 0.5% of PMMA-COOH and (2) 0.5% PMMA-COOH with encapsulated ICG (indocyanine green) were fabricated.

The experimental method was carried out at room temperature and ambient humidity. The parameters of the present composition controlled high field electro hydrodynamic experimental method are described in Table 1.

Table 1.

S.NO. PMMA- ICG So lvent Fk lie Voltage/TCD COOH (mg) m) (m 1 hr) (KV/cm)

(mg)

_ 1 __ 30___ __ 0__ (■ 2 2.85

9 2.85 ] Post-Processing

] The nanoparticle suspension was then centrifuged 18 at 10,000G for a period of 15 minutes to remove the small amount of larger particles (>150nm). This produces a supernatant 18, The supernatant was then subjected to additional centrifuge 22 at 30,000G for Ihr to produce a precipitate 24. The precipitated pellet obtained from the centrifugation is soiubilized 26 and then sonicated 28 for 15mins. This produces monodisperse nanoparticles 30, which include a COOH surface functionality 32. Surface modifications 34 can then be performed, such as to associate a payload via surface attachment.

] Various adjustments can modify the size of the particles. The centrifugal speed is an example. It is possible to carry out size separation using various different media at various different speed and time. In addition, other forms of purification including filtration and subjecting to various gyration forces will also yield similar results.

] Encapsulation

] Encapsulation of therapeutic agents including drugs, proteins, and diagnostic agents including dyes and contrast agents was carried out experimentally. The agent(s) (individually or in combination), are dissolved or suspended homogenously in the solvent along with the polymers in step 10. Complete entrapment of molecules within nanoparticles during the experimental method was achieved. Payloads have different properties have been incorporated to demonstrate the robust nature of the present method, including two different payloads, such as therapeutic and contrast payloads. A nanoparticle 40 is represented in FIG. 2 with COOH groups 42 and first 44 and second 46 payload molecules,

] Surface modification - PEGylation

] The inherent presence of carboxyl group (-COOH) present on the surface of the nanoparticles resultant from the formation technique and materials was utilized for the surface modification. FIG. 3A illustrates the process. Polyethylene glycol with one end group consisting of amine was conjugated to the carboxyl group of nanoparticles through EDC/NHS reaction. In brief the nanoparticles pellet, obtained from the postprocessing step, was suspended in 2-(N-morpholino)ethanesulfonic acid (2-(N- moq3hoiino)ethanesulfonic acid (MES) buffer. The concentration of the nanoparticles in the buffer was approximately Img/ml. 17mg of EDC and lOmg of NHS dissolved in 1ml of MES buffer and was then added to the nanoparticles solution to produce an intermediate 50. The reaction was carried out for 3hrs. Thereafter, the carboxyl activated nanoparticles were washed with MES and the excess EDC and NHS were removed to produce a second intermediate 52.

In order to conjugate PEG to the surface of the nanoparticles, the nanoparticles were re-suspended in PBS buffer and NH2-PEG-COOH was added in excess. Overnight reaction allowed the chemical conjugation of PEG onto the surface of the nanoparticles through NH+-COO- linkage between PEG and nanoparticles 54. The presence of COOH group present as end termination in PEG can further be uti lized for antibody or ligand attachment in further fuiictionalizatioii 56. Alternatively, antibody and/or liga d could be functionalized to the surface of nanoparticles during the PEGylation step as a simultaneous reaction. FIG. 3B shows the alternative, where the encapsulated compound polymer particles are form in a first stage, the PEGylation is a second stage that includes antibody additional in a third stage.

Particle size characterization

The hydrodynamic size of the nanoparticles was characterized using dynamic light scattering method. Malvern Zetasizer Nano ZS was used for determining the particle size distribution. In addition, Transmission Electron Microscopy (TEM) was used to confirm the results from DLS measurements.

The size of the nanoparticles with encapsulated as well as pristine nanoparticles (with no encapsulated compound) is detailed in Table 2. Representative TEM images and Dynamic Light Scattering (DLS) results of the nanoparticles are shown in FIGs. 4A, 4B and 5. Various nanoparticles synthesized using the present method were found to be in the average size ranging from 50-90nm, with low polydispersity index (PDI). The size of the nanoparticles increased by 15nm after PEGylation, as shown in FIG. 5, indicating the presence of surface bound PEG molecules. In addition, no major change in the size was observed even with five-fold increased concentration of encapsulated ICG. TEM images confirm highly dispersed, non-aggregated, spherically shaped uniform nanoparticles. T able 2

[0089] Loading efficiency

[0090] The loading efficiency of the encapsulated compound was computed UV-Vis-NIR.

spectroscopy. As an example, the amount of ICG present within PMMA-COOH was determined by dissolving the polymeric nanoparticles in methanol solution. The absolute value of absorption was then correlated to the calibration curve of ICG in methanol to determine the content of ICG present within the system. The % encapsulation was then calculated based on the fol lowing equation,

% Encapsulation = X 100,

[0091] where, Md is the mass of the ICG determined using spectroscopic analysis, and MdO is the initial dye loading during the start of the present composition controlled high field eleetrohydrodynamie method. FIG. 6 shows the UV-VIS spectroscopic analysis of ICG content present within the nanoparticles.

[0092] Nanoparticles synthesized through the present method with lOmg ICG and 30mg

PMMA-COOH (initial content) were collected in 20ml DI water. Theoretically, Img of nanoparticles, if 100% encapsulation were to be obtained, would contain 750p.g of polymer and 250,ug of ICG. Based on calibration curve of ICG, it was determined that the amount of ICG present, after washing the surface bound ICG, to be approximately 165mg. Thus, to confirm the amount of encapsulated compound, the solutions were suitable diluted to 10 μ§/ηη1. The final sample for analysis consisted of 950μ1 of methanol and 50μ1 of DI water for both ICG and nanoparticles. It was evident from the analysis, as shown in Figure 6, that equal amounts of ICG, namely, I65ug, is present in both the sample solutions. Hence, the encapsulation efficiency was computed to be 65%.

[0093] Stability studies

[0094] Stability of the nanoparticles was characterized by incubating the nanoparticles in DI water at 25°C for a period of 7 days. The size and the zeta potential of the nanoparticles were investigated at period intervals of 24hrs to determine if any form of degradation or aggregation had occurred. For this study 0.5% w/w polymer concentration was used in the present composition controlled high field electrohydrodynamic method and the nanopartieuiate suspension was filtered through 0.2 micron Cellulose Acetate filters. The stability analysis of pristine nanoparticles in detailed in FIG. 7.

[0095] It can be observed from the data in FIG. 6 that the Pristine PMMA-COOH nanoparticles are highly stable and experience almost no size range (mono disperse nanoparticles are obtained). The slight increase in the size of the nanoparticles suspended in DI water could be attributed to swelling of the nanoparticles. Lack of aggregation of the nanoparticles is shown due to (i) no significant size increase is observed, and (ii) the absolute value of PDI below 0.2 remains almost constant as well.

[0096] In- Vivo studies

[0097] Near Infrared based florescent imaging was carried out in nude mice through IVIS in- vivo imaging system. Briefly, Ι ΟΟμΙ of samples of free ICG solution (0.15mg/ml) , PMMA-COOH (0.15mg/ml of ICG present in nanoparticles) and Pegylated nanoparticles containing ICG (Q.l Smg/ml) were injected once and their florescence were recorded at various time points as shown in FIGs. 8A-8C. The results showed that the florescence of free ICG diminished within 6hrs and was completely reduced to almost zero within 24hrs; whereas, the NIR florescence of PMMA-COOH was retained for 12hrs before completely diminishing. On the other hand, Pegylated nanoparticles showed florescence for a longer period of time with low florescence present even after 48hrs. There are three possible reasons for florescence quenching; namely, (i) degradation of free ICG in physiological conditions, or (ii) rapid clearance of free ICG from the body, or (iii) a combination of both processes.

[0098] It can be inferred from FIG. 7 that Pegylated nanoparticles show higher florescence than the non Pegylated nanoparticles and free ICG solution, for the following reasons. Firstly, had there been a release of ICG from the nanoparticles, the florescence should have quenched within 6 hours, which did not occur, as observed in free ICG solution. Second, when nonPEG-nanoparticles is compared with ICG solution, the florescence was intact for a longer period of time for nanoparticles. Therefore, the following conclusions could be drawn by the above two observations: (i) ICG remained intact and encapsulated within the nanoparticles, and (ii) PEGylation of nanoparticles increased the blood circulation time.

Quantitative analysis of mean intensity with respect to time confirmed the above observations as shown in FIG. 9, These results are a very positive indication for utilization of the candidate for selective and targeted release. A matrix which does not allow the leakage of the encapsulated molecule can be used for releasing the therapeutic agent at the desired locations. In other words, even if certain percentage of the nanoparticle complex does not target the desired locations, the therapeutic agent would not release and hence would not cause undesired harm to healthy cells.

While specific embodiments of the present invention have been shown and described, it should be understood that other modifications, substitutions and alternatives are apparent to one of ordinary skill in the art. Such modifications, substitutions and alternatives can be made without departing from the spirit and scope of the invention, which should be determined from the appended claims.

Various features of the invention are set forth in the appended claims.