FLUID SAMPLE COLLECTION DEVICE

CROSS-REFERENCE

[0001] This application claims the benefit of Chinese patent Application No 200710068555 X, filed May 1 1 , 2007, which application is incorporated herein by reference in its entirety

BACKGROUND OF THE INVENTION

[0002] Fluid sample collection devices are widely used in clinics and hospitals to collect from patients bodily fluids, such as saliva, unne, blood, and other samples However, the conventional collection devices particularly saliva collection devices, suffer fiom a number of profound drawbacks For example, a typical saliva collection device permits reflux of saliva fluid collected, which often causes contamination with other chemical reagents contained in the device A conventional design typically uses a swab which is softened after absorbing saliva When an external force is applied to the softened swab, collected saliva sample can be squeezed out and leflux takes place Such pheromone not only affects the subsequent test to be run with the collected sample, but also can cause significant psychological distress to the individual from which the sample is to be collected In addition, using certain conventional saliva collection devices, it is often difficult to determine whether a sufficient amount of sample has been collected. Insufficiency of sample volume is often a pioblem when testing for drug abuse These individuals usually have relatively dry mouths and they often intentionally provide insufficient saliva for testing

SUMMARY OF THE INVENTION

[0003] The piesent invention provides devices and kits useful foi collecting fluid samples [0004] Accordingly, in one embodiment provided is a fluid sample collection device comprising (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material, wherein the collection member and the indicator assembly are in fluid communication, and wherein the indicator assembly has a fluid-retention capability greater than that of the collection member Where desired, the first absorbent material and the second absorbent material are the same or different material

[0005] In another embodiment provided is a fluid sample collection device comprising (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material different from the first absorbent material, wherein the device is configured to permit a fluid sample to flow from the collection member to the indicator

assembly, and wherein the device is configured to restrict substantially all of the flow of the fluid from the indicator assembly to the collection member.

[0006J In one aspect, the first absorbent material and the second absorbent material of any of the subject devices have different porosity. In another aspect, the first absorbent material is more porous than the second absorbent material. In another aspect, the first absorbent material has larger pores than the second absorbent material. Where desired, the first absorbent material is selected from the group consisting of polyvinyl alcohol, foaming polyvinyl alcohol, resin, crosslinked polyacrylic acid sodium salt, polyacrylic acid, polyvinyl alcohol - polyacrylic acid copolymer, polyacrylonitrile, polyacrylonitrile with saponification, styrene-acrylonitrile, vinyl polymers, cotton fiber, sponge, and any combination thereof. The first absorbent can be made of a material for absorbing and storing the fluid sample using at least one chemical absorption method. The chemical absorption means can involve hydrogen bonding and/or van der waals force. In another aspect, the second absorbent material is selected from the group consisting of filter paper, Bolivian filament, adhesive-bonded cloth, acetate fiber, and any combination thereof. The second absorbent can be of a material that absorbs fluid by capillary action. Where desired, the second absorbent material comprises filter paper.

[0007] In yet another aspect, the indicator assembly of a subject device comprises at least one indicator. The indicator can comprise at least one coloring reagent for showing that sufficient fluid sample has been collected. The indicator can also comprise at least one pigment (e.g., food coloring). A suitable coloring reagent can be any reagent that has one or more of the following characteristics: (i) capable of creating significant color change; (ii) capable of maintaining color within an amount of time sufficient for diagnostic purpose; (iii) capable of showing stable color insensitive to light; (iv) non-toxic to animals including human; and (v) substantially incapable of interfering with a diagnostic assay for detecting an analyte suspected to be present in said sample. In some aspects, the indicator comprises a substrate of an enzyme (e.g., amylase) that is expected to be found in the fluid sample. In another aspect, the indicator comprises a colored material covered by an opaque layer, wherein said opaque layer becomes transparent upon being wetted by the fluid sample for showing that sufficient fluid sample has been collected. The opaque layer can be the second absorbent material. In yet another aspect, the indicator used in any of the subject device comprises a pH indicator that can detect the pH value of the fluid sample to be collected. A desirable pH indicator changes color after interacting with the fluid sample. In still another aspect, the indicator can be a temperature indicator. Where desired, the temperature indicator comprises a temperature-sensitive reagent capable of showing temperature of the fluid sample. The temperature-sensitive reagent can be a polyamide.

[0008] In some instances, the indicator comprises a conjugate configured to bind to an analyte of interest that is expected to be found in the fluid sample The analyte can include but are not limited to drugs, prodrugs, pharmaceutical agents, drug metabolites, biomarkers such as expressed proteins and cell markers, antibodies, serum proteins, cholesterol, polysaccharides, nucleic acids, biological analytes, biomarker, gene, protein, viral antigens, or hormone, or any combination thereof At a molecular level, the analytes can be polypeptide glycoprotein, polysaccharide, lipid, nucleic acid, and a combination thereof

[0009] Where desired, the subject sample collection device can be configured to comprise a plurality of indicators The plurality of indicators can be of the same or different kind for indicating the same or different physical and/or chemical properties of the fluid sample collected The plurality of indicators can be selected from the group consisting of a pH indicator, a temperature- sensitive reagent, a colored material, and a substrate of an enzyme that is expected to be found in the fluid sample [0010] In some instances, the subject device further comprises a window for viewing the indicator The window can be a hole or a transparent region made of transparent material Where desired, the indicator assembly compπses a reading region comprising a plurality of zones, wherein at least one zone is a sample receipt zone, a marker zone, a result control zone, and a sample retaining zone [0011 ] In some other instances, the subject device comprises a handle In some instances, at least a portion of the handle is transparent

[0012] The present invention also provides methods of using the subject devices to collect fluid sample Accordingly, provided is a method for collecting fluid sample fiom a subject into a fluid sample collection device that comprises a collection member and an indicator assembly The method typically comprises the step of contacting a fluid with a first absorbent material of the collection member, the first absorbent material collecting the fluid sample from the fluid, the fluid flowing from the first absorbent material to a second absorbent material of the indicator assembly, and the indicator assembly indicating the presence of a sufficient amount of the fluid sample collected by the collection member [0013) In another embodiment, the present invention provides a method for collecting a fluid sample from a subject The method typically compπses the step of contacting a fluid with a first absorbent mateπal of the collection member, the first absorbent material collecting the fluid sample from the fluid, and the fluid flowing from the first absorbent material to a second absorbent mateπal of the indicator assembly, wherein the indicator assembly has fluid-retention capability greater than the fluid-retention capability of the collection member

[0014] Any of the devices disclosed herein can be utilized to practice the subject methods. The subject methods can be applied for collection of a variety of fluid samples. Non-limiting examples of bodily fluid that can be collected by the subject methods include blood, serum, saliva, urine, gastric and digestive fluid, tears, semen, sweat, vaginal fluid, interstitial fluids, and cerebrospinal fluid.

[0015] Also provided in the present invention is a kit comprising a sample collection device disclosed herein. A subject kit typically further comprises instructions instructing how to use the device. The subject kit can further a container for protecting the collection member from contamination at least prior to use.

INCORPORATION BY REFERENCE

[0016] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS [0017] The novel features of the invention are set forth with particularity in the appended claims.

A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:

[0018] Figure 1 shows an exemplary embodiment of disclosed fluid collection device. [0019] Figure 2 shows various parts of an exemplary embodiment of disclosed fluid collection device in explosive view.

[0020] Figure 3 shows various parts of an exemplary embodiment of disclosed indicator assembly in explosive view.

[0021] Figure 4A shows an exemplary embodiment of disclosed fluid collection device before use. Figure 4B shows the same device after use where sufficient fluid sample has been collected.

[0022] Figure 5 shows another view of an exemplary embodiment of disclosed fluid collection device.

DETAILED DESCRIPTION OF THE INVENTION Devices [0023] Disclosed are devices, kits, and methods for fluid sample collection to substantially prevent reflux of the fluid sample from the indicator assembly of the device back to the collection member of the device and/or to ensure collection of sufficient fluid sample.

[0024] Accordingly, in one embodiment the present invention provides a fluid sample collection device comprising: (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material, wherein the collection member and the indicator assembly are in fluid communication, and wherein the indicator assembly has fluid- retention capability greater than the fluid-retention capability of the collection member. In one aspect, the indicator assembly has fluid-retention capability that is at least about 50%, 100%, 200%, 300%, 400%, 500%, 1000% or greater than that of the collection member. [0025] In some embodiments, the first absorbent material and the second absorbent material are of different materials. In some embodiments, the first absorbent material and the second absorbent material are the same material.

[0026] Additionally provided herein is a fluid sample collection device comprising: (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material different from the first absorbent material, wherein the device is configured to permit a fluid sample to flow from the collection member to the indicator assembly, and wherein the device is configured to restrict substantially all of the flow of the fluid from the indicator assembly to the collection member.

[0027] As used herein, restricting substantially all of the flow of the fluid from the indicator assembly to the collection member (i.e. to substantially prevent reflux) can mean at least one of the following: only an undetectable amount of the fluid flows from the indicator assembly to the collection member, an amount not noticeable to the subject of the fluid flows from the indicator assembly to the collection member, no more than 1/1000 of the fluid sample flows from the indicator assembly to the collection member, no more than 1/500 of the fluid sample flows from the indicator assembly to the collection member, no more than 1/200 of the fluid sample flows from the indicator assembly to the collection member, no more than 1/100 of the fluid sample flows from the indicator assembly to the collection member, no more than 1/50 of the fluid sample flows from the indicator assembly to the collection member, no more than 1/20 of the fluid sample flows from the indicator assembly to the collection member, no more than 1/10 of the fluid sample flows from the indicator assembly to the collection member. [0028] In some embodiments of the fluid sample collection devices disclosed herein, the first absorbent material and the second absorbent material having different porosity. The first absorbent material may be more porous than the second absorbent material. The first absorbent material may have larger pores than the second absorbent material.

[0029] In some embodiments, the devices disclosed use the same material having different physical dimensions and/or properties, for non-limiting example, different sizes of pores, for

absorbing fluid differently. In one example of the disclosed devices, the collection member is made of a filter paper having relatively large pores for absorbing large amount of fluid In the same example, the indicator assembly comprises a filter paper having relatively small pores for absorbing small amount of fluid where the filter paper having small pores has stronger capability for retaining fluid According, after the fluid moves from the collection member to the indicatoi assembly, the fluid will be retained within the indicator assembly (due to the stronger capability for retaining fluid) and the fluid retained by the indicator assembly will be substantially prevented from reflux back to the collection member Even the collected fluid is squeezed out of the collection member later, substantially all of the fluid that flowed to the indicator assembly will still be retained within the indicator assembly and not flow back to the collection member [0030| In some embodiments of the fluid sample collection devices disclosed herein, the fust absorbent material comprises foaming polyvinyl alcohol, and the second absorbent material comprises filter paper. Foaming polyvinyl alcohol absorbs fluid mainly by way of hydrogen bonding and Van der Waals force After being wetted by fluid, foaming polyvinyl alcohol becomes softening and flexible When the foaming polyvinyl alcohol of the collection member is saturated for retaining a fluid, the fluid flows to the filter paper of the indicator assembly, where the filter paper absorbs the fluid mainly using capillary action [0031] Capillary action refers to an ability of a substance to draw fluid into it Typically capillary action occurs when the adhesive intermolecular force between the substance and the fluid is greater than the cohesive forces inside the fluid Surface tension can pull the fluid into a porous substance. Filter papers have many tiny porous structures for absorbing fluid using capillary action The fluid in the foaming polyvinyl alcohol of the collection member typically forms a concave meniscus and the surface tension can push the fluid into the filter paper's porous structures. When the force created by the surface tension equals to the gravitational force, the fluid stops flowing and the filter paper stop absorbing the fluid. Because the filter paper's porous structures form a web-like arrangement and the absorbed fluid is free to flow in any direction within the web-like arrangement, the filter paper has fluid-retention capability greater than the fluid-retention capability of foaming polyvinyl alcohol [0032] In a separate but related embodiment, provided herein is a fluid sample collection device comprising a collection member comprising a first absorbent mateπal, and an indicator assembly comprising a second absorbent mateπal different from the first absorbent material, wherein the collection member and the indicator assembly are in fluid communication, and wherein said indicator assembly is configured to indicate the presence of a sufficient amount of fluid sample collected by the collection member

[0033] In some embodiments, the indicator assembly comprises a coloring material covered by an opaque layer, wherein said opaque layer becomes transparent by interacting with the fluid sample. In some embodiments, before collection of a fluid sample, the coloring material is not visible due to the coverage of the opaque layer. When sufficient amount of the fluid sample has been collected, in some embodiments, the opaque layer interacts with the fluid sample and becomes transparent. As a consequence, the coloring material becomes visible showing that sufficient amount of the fluid sample has been collected and the collection process can be stopped. [0034) A sufficient amount of fluid sample refers to a sample volume that is sufficient to trigger a signal from the indicator of the device. This occurs, for example, when the sample collected triggers a showing of (i) colored material of the indicator; (ii) the expected temperature; (iii) the expected pH of the fluid sample; (iv) reaction with enzyme in the fluid sample; (v) transparent layer; or (vi) any combination thereof. In one aspect, an amount of fluid sample is sufficient if it contains enough of an analyte of interest for subsequent testing. [0035| In some embodiments, the indicator assembly of the subject device comprises at least one indicator. The indicator may include at least one coloring reagent for showing that sufficient fluid sample has been collected. The coloring reagent may include a single pigment or a plurality of pigments. The pigment may be food coloring, or another pigment that is visually distinguishable. The pigment may be, for non-limiting example, food coloring or another pigment. The food coloring can be either natural product or synthetic product (artificial coloring). Examples of food coloring include Brilliant Blue FCF (FD&C Blue No. 1 , E133), Indigotine (FD&C Blue No. 2, E 132), Fast Green FCF (FD&C Green No. 3, E 143), Allura Red AC (FD&C Red No. 40, E129), Erythrosine (FD&C Red No. 3, E127), Tartrazine (FD&C Yellow No. 5, El 02), and Sunset Yellow FCF (FD&C Yellow No. 6, El 10). The coloring reagent may be capable of creating significant color change. The coloring reagent may be capable of maintaining color within a reasonable amount of time for diagnostic purpose, for example, for at least ten minutes. The coloring reagent may be capable of showing stable color insensitive to light. The coloring reagent may be non-toxic to animals including human. The coloring agent may be substantially incapable of interfering with subsequent testing. [0036] In some embodiments of the fluid sample collection device, the indicator comprises a substrate of an enzyme that is expected to be found in the fluid sample. The enzyme may be, for non-limiting example, amylase. In some embodiments, the at least one coloring reagent comprises a substrate of an enzyme in the fluid sample. The substrate of enzyme can be specific to a particular type of fluid sample. For example, human saliva samples contain amylase and

salivary lipase where both cannot be found in human urine samples. By using a substrate specific to amylase as the coloring reagent, color change will only be observed when saliva samples are collected but not urine samples.

[0037] In some embodiments of the fluid sample collection device, the indicator comprises a colored material covered by an opaque layer, wherein said opaque layer becomes transparent upon being wetted by the fluid sample for showing that sufficient fluid sample has been collected. In some embodiments of the fluid sample collection device, the indicator comprises a colored material covered by an opaque layer, wherein said opaque layer becomes transparent upon being wetted by the fluid for showing that sufficient fluid sample has been collected. The opaque layer may be the second absorbent material, or it may be another material that becomes transparent upon being wetted by a fluid. In some embodiments, the colored material is water- absorbent. In some embodiments, the colored material is not water absorbent. In some embodiments, the opaque layer undergoes an interaction with the fluid and/or the fluid sample upon being wetted by the fluid and/or the fluid sample to reveal the colored material. In some embodiments, before collection of a fluid sample, the coloring material is not visible due to the coverage of the opaque layer. When sufficient amount of the fluid sample has been collected, in some embodiments, the opaque layer interacts with the fluid sample and becomes transparent. As a consequence, the coloring material becomes visible showing that sufficient amount of the fluid sample has been collected and the collection process can be stopped. [0038] In some embodiments of the fluid sample collection device, the indicator comprises a pH indicator. The pH indicator may be capable of changing color after interacting with the fluid sample. The color change of the pH indicator may show pH value of the fluid sample. For non- limiting example, human's saliva samples usually have a pH value around 7 during fasting and a lower pH value after a meal. Human's urine samples usually have a pH value between 5 to 7. Human's blood samples usually have a pH value around 7.35. The pH indicator can indicate the pH to the accuracy desired for the specific sample taken. For non-limiting, for pH testing of urine, the pH indicator could range from about 5 to 7, with increments of about 0.1 to 0.5. For non-limiting example, for pH testing of saliva, the pH indicator could range from about 6 to 8, with increments of about 0.1 to 0.2. For non-limiting example, for pH testing of blood, the pH indicator could range from about 6.5 to 7.5, with increments of about 0.01 to 0.05.

[0039] In some embodiments of the fluid sample collection device, the indicator comprises a temperature indicator. The temperature indicator may be, for non-limiting example, a temperature-sensitive reagent showing temperature of the fluid sample. The temperature indicator may be, for non-limiting example, polyamide.

[0040] In some embodiments of the fluid sample collection devices disclosed herein, the indicator assembly further comprises a plurality of indicators, e.g., 2, 3, 4, 5, or more indicators of the same or different types. One or more of the indicators can be selected from the following types: (i) a pH indicator; (ii) a temperature-sensitive reagent; (iii) a colored material; (iv) a substrate of an enzyme that is expected to be found in the fluid sample; or (v) a combination of one or more types from (i)-(iv).

[0041] In some embodiments of the fluid sample collection devices disclosed herein, the indicator assembly comprises a reading region, wherein the reading region comprises a plurality of zones, wherein at least one zone is a sample receipt zone, a marker zone, a result control zone, and a sample retaining zone. The sample receiving zone may be connected to the collection member. The marker zone may contain at least one reagent showing temperature and/or pH of the fluid sample. The result control zone can show that sufficient amount of the fluid sample has been collected. The result control zone can also contain at least one reagent for a diagnostic purpose. The sample retaining zone can retain excess fluid, for non-limiting example, where the device disclosed prevents reflux back to the collection member.

[0042] In some embodiments, the indicator of the subject device may test for drug presence, for non-limiting example, nicotine, cocaine, amphetamine (e.g. black beauties, white bennies, dextroamphetamines, dexies, beans), methamphetamine (e.g. crank, meth, crystal, speed), sedatives (e.g. sleep aids), narcotics, barbituates, lysergic acid diethylamide (LSD), opiates (e.g. morphine, opium, codeine, heroin, oxycodone), antidepressants (e.g. TCA, imipramine, amitriptyline, doxepin), depressants (downers, goofballs, barbs, blue devils, yellow jackets, hides), phencyclidine (PCP), tetrahydrocannabinol (e.g. TCH, marijuana, pot, dope, hash, weed), and/or pain medications. For example, employers may wish to determine if an employee or a potential employee is using illegal drugs. Emergency rooms may want to determine what drug an overdose patient has used. Probation officers may want to determine if a parolee is using illegal drugs. In some embodiments of the fluid sample collection devices disclosed herein, the indicator may test for medical conditions, for non-limiting example, hepatitis (A, B, and/or C), HIV, cancer, fertility, an allergy. The devices disclosed herein may be used for collecting samples for screening and/or diagnostic purposes. [0043] In some embodiments, the indicator comprises a conjugate configured to bind to an analyte of interest. In some embodiments the analyte is an antigen, in which case, the indicator comprises an immobilized antibody. In some embodiments, the analyte is an antibody, in which case, the indicator comprises an immobilized antigen.

[0044] An analyte of interest (or analyte) is any molecule or compound whose presence is to be identified in the fluid sample. An analyte may include, without limitation, viral antigens, bacterial antigens, hormones, such as insulin, follicle stimulating hormone, thyrotropin, relaxin, somaotropin and gonadotropin, enzymes, immunoglobulins, cytokines, drugs, cancer antigens, antigenic polysaccharides, and nucleic acids. Others may include anti-HIV antibodies. In other embodiments, and analyte is a compound or composition to be measured that is capable of binding specifically to a ligand, receptor, or enzyme, usually an antibody or antigen such as a protein or drug, or a metabolite. Analytes can include antibodies and receptors, including active fragments or fragments thereof. An analyte can include an analyte analogue, such as, for non- limiting example, an analyte altered by chemical or biological methods, such as by the action of reactive chemicals, such as adulterants or enzymatic activity.

[0045] A conjugate is a composition that is configured to bind to an analyte of interest and produce a detectable signal. The conjugate typically comprises a binding component conjugated to a label. The binding component allows the conjugate to bind to the analyte of interest and optionally to a control compound. The label produces a detectable signal, preferably a visual signal. In one embodiment, the visual signal is produced only upon binding of the conjugate to the analyte. In another embodiment, the analyte of interest is an antibody, and the conjugate comprises a binding component that is able to bind to antibodies. In another embodiment, the analyte of interest is an antigen, and the binding component of the conjugate comprises an antibody that is able to bind to the antigen. The antibody may be a monoclonal antibody.

[0046] In some embodiments, the subject fluid sample collection devices are made of at least two different types of absorbent materials. For instance, the collection member is made of a first absorbent material and the indicator assembly is made of a different material. The first absorbent material can be, e.g., at least one of polyvinyl alcohol, foaming polyvinyl alcohol, resin, crosslinked polyacrylic acid sodium salt, polyacrylic acid, polyvinyl alcohol - polyacrylic acid copolymer, polyacrylonitrile, polyacrylonitrile with saponification, styrene-acrylonitrile, vinyl polymers, cotton fiber, sponge, and any combination thereof. The first absorbent can also be made of materials capable of absorbing and storing the fluid sample by way of a chemical absorption method. The chemical absorption method includes but is not limited to hydrogen bonding and/or van der waals force to facilitate interactions between fluid and hydrophilic substances.

[0047] The first material can comprise high molecular compound which is hydrophilic for collecting and storing fluid samples. Many hydrophilic polymers can collect fluid using hydrogen bond and/or Van der Waals force with limited help from capillary method. When

certain hydrophihc groups hydrolyze, cations and anions will repel each other to create osmosis pressure to further attract fluid When the repelling forces between cations or anions reach equilibrium, no more fluid will be further attracted and therefore the collected fluid reaches a saturation status

^ [0048] In some embodiments, the collection member can be made of a materials selected from the group consisting of polyvinyl alcohol, foaming polyvinyl alcohol, resin, crosslinked polyacrylic acid sodium salt, polyvinyl alcohol - polyacrylic acid copolymer, polyacrylonitπle, polyacrylonitπle with saponification, styrene-acrylonitπle, vinyl polymers, and any combinations thereof Certain polymers containing polyvinyl alcohol can absorb fluid relatively fast - reaching 50% saturation within two or three minutes Other suitable materials for the collection member include high molecular polymers derived from proteins (amino acids), carbohydrates (polysaccharides), or fibers Examples of polysaccharides suitable for the collection member include polymer containing agarose and/or chitin [0049] In some embodiments, the collection member is made of forming polyvinyl alcohol Dry forming polyvinyl alcohol has a hard and solid texture After absorbing fluid, wet forming polyvinyl alcohol becomes soft and flexible Forming polyvinyl alcohol is also strong and stable enough to endure most sterilization procedures In some embodiments, the collection member comprises at least one reagent for stimulating a patient's saliva gland The use of the reagent for stimulating a patient's saliva gland can facilitate and accelerate the collection of saliva samples In some embodiments, the reagent for stimulating a patient's saliva gland is citric acid

[0050] In some embodiments, the indicator assembly of the subject fluid sample collection is made of a material that different from that of the collection member This second material for the indicator assembly can include without limitation filter papei, Bolivian filament, adhesive- bonded cloth, acetate fiber, and any combination thereof In some embodiments, the absorbent material for the indicator assembly comprises filter paper In some embodiments, the mateπal for the indicator assembly absorbs fluid using capillary action

[0051 ] In some embodiments of the fluid sample collection devices disclosed herein, the device further comprises a handle At least a portion of the handle may be transparent The device may additionally and/or alternatively comprise a window for viewing an indicator The window may include a hole. The window may include a transparent material In some embodiments, the window is for viewing a signal when sufficient fluid sample has been collected In some embodiment, the signal results from movement of pigment in the indicator assembly

Methods of Use

[0052] The subject devices provide an effective means for collecting fluid samples. The subject devices have a broad spectrum of utility in, e.g. drug screening, disease diagnosis, phylogenetic classification, parental and forensic identification. The subject devices are also particularly useful for advancing preclinical and clinical stage of development of therapeutics, improving patient compliance, monitoring adverse drug response associated with a prescribed drug, and developing individualized medicine.

[0053] Accordingly, provided herein is a method for collection of a fluid sample from a subject into a subject fluid sample collection device. The method comprises the step of contacting a fluid with a first absorbent material of the collection member, the first absorbent material collecting the fluid sample from the fluid, the fluid flowing from the first absorbent material to a second absorbent material of the indicator assembly, and the indicator assembly indicating the presence of a sufficient amount of the fluid sample collected by the collection member. [0054] In a separate but related embodiment, the present invention provides a method for collection of a fluid sample from a subject into a fluid sample collection device, wherein the device comprise collection member and an indicator assembly. The method involves the step of contacting a fluid with a first absorbent material of the collection member, the first absorbent material collecting the fluid sample from the fluid, and the fluid flowing from the first absorbent material to a second absorbent material of the indicator assembly, wherein the indicator assembly has fluid- retention capability greater than the fluid-retention capability of the collection member. [0055] In another embodiment, provided is a method for collection of a fluid sample from a subject into a fluid sample collection device which comprises a collection member and an indicator assembly. The method involves contacting a fluid with a first absorbent material of the collection member, the first absorbent material collecting the fluid sample from the fluid, and the fluid flowing from the first absorbent material to a second absorbent material of the indicator assembly, wherein the device is configured to restrict substantially all of the flow of the fluid from the indicator assembly to the collection member.

[0056] The subject methods are applicable for collecting fluid samples from any subject. For example, such subject can be an animal, including but not limited to murines, simians, humans, farm animals, sport animals, and pets. [0057] The subject methods can be applied for collection of a wide range of fluids from a subject. Non-limiting examples of fluids include blood, serum, saliva, urine, gastric and digestive fluid, tears, semen, sweat, vaginal fluid, interstitial fluids, and cerebrospinal fluid. The blood sample may be whole blood, serum, plasma, and/or any combination of blood constituents.

[0058] Collection of a fluid sample with a subject device typically proceeds with contacting the device with the fluid to be collected. Fluid is allowed to contact the collection member first, which absorbs the fluid. The fluid then flows from the collection member into the indicator assembly. In some aspects, the indicator assembly has a higher fluid-retention capability that that of the collection member. As a result, fluid absorbed is more likely to be retained in the indicator assembly, and reflux flow of the collected fluid is substantially reduced or prevented. When using a subject device comprising an indicator capable of showing a sufficient amount of fluid has been detected, one will remove the device from the source of the fluid once such indicator is turned on. [0059] In some embodiments, the method comprises the indicator coloring to indicate that sufficient fluid sample has been collected, wherein the indicator comprises at least one coloring reagent. The coloring may comprise at least one of intensifying color, and changing color. The coloring reagent may comprise, for non-limiting example, a pigment. The pigment may be, for non-limiting example, food coloring or another pigment. The food coloring can be either natural product or synthetic product (artificial coloring). Examples of food coloring include Brilliant Blue FCF (FD&C Blue No. 1 , El 33), Indigotine (FD&C Blue No. 2, El 32), Fast Green FCF (FD&C Green No. 3, E143), Allura Red AC (FD&C Red No. 40, E129), Erythrosine (FD&C Red No. 3, E127), Tartrazine (FD&C Yellow No. 5, E102), and Sunset Yellow FCF (FD&C Yellow No. 6, El 10). The method may comprise revealing a colored material to indicate that sufficient fluid sample has been collected. The method may include the coloring reagent creating significant color change. The method may include the coloring reagent maintaining color within a reasonable amount of time for diagnostic purpose, for example, for at least ten minutes. The method may include the coloring reagent showing stable color insensitive to light. The method may include the coloring reagent being non-toxic to animals including human. The method may include the coloring reagent not interfering with subsequent diagnostic assays. [0060] In some embodiments of the methods provided herein, the indicator reacting with an enzyme that is expected to be found in the fluid sample, wherein the indicator comprises a substrate of the enzyme. In some embodiments, the enzyme is amylase. In some embodiments, the at least one coloring reagent comprises a substrate of an enzyme in the fluid sample. The substrate of enzyme can be specific to a particular type of fluid sample. For example, human saliva samples contain amylase and salivary lipase where both cannot be found in human urine samples. By using a substrate specific to amylase as the coloring reagent, color change will only be observed when saliva samples are collected but not urine samples.

[0061] In some embodiments of the methods provided herein, the method comprises the indicator showing a colored material when an opaque layer covering the colored material is wet by the fluid sample, wherein said opaque layer becomes transparent upon being wetted by the fluid sample In some embodiments, the opaque layer is the second absorbent material. In some embodiments, the opaque layer is a material other than the second absorbent matenal In some embodiments, the opaque layer interacts with the fluid and/or the fluid sample to reveal the colored material. In some embodiments, the opaque layer dissolves when wetted by the fluid and/or the fluid sample In some embodiments, before collection of a fluid sample, the coloring material is not visible due to the coverage of the opaque layer When sufficient amount of the fluid sample has been collected, in some embodiments, the opaque layer interacts with the fluid sample and becomes transparent As a consequence, the coloπng matenal becomes visible showing that sufficient amount of the fluid sample has been collected and the collection process can be stopped [0062] In some embodiments of the methods provided herein, the method comprises the indicator interacting with fluid sample and the indicator showing the pH of the fluid sample, wherein the indicator comprises a pH indicator. The showing of the fluid sample pH may be achieved, for non-limiting example, by the pH indicator changing color after interacting with the fluid sample In some embodiments, the color change of the pH indicator shows pH value of the fluid sample For non-limiting example, human's saliva samples usually have a pH value around 7 during fasting and a lower pH value after a meal Human's urine samples usually have a pH value between 5 to 7. Human's blood samples usually have a pH value around 7.35 The pH indicator could indicate the pH to the accuracy desired for the specific sample taken. For non- hmiting, for pH testing of urine, the pH indicator could range from about 5 to 7, with increments of about 0 1 to 0 5 For non-limiting example, for pH testing of saliva, the pH indicator could range from about 6 to 8, with increments of about 0.1 to 0 2 For non-limiting example, for pH testing of blood, the pH indicator could range from about 6.5 to 7 5, with increments of about 0.01 to 0 05

[0063] In some embodiments of the methods piovided herein, the method comprises the indicator showing temperature of the fluid sample, wherein the indicator comprises a temperature-sensitive reagent The temperature-sensitive reagent may comprise, for non- hmiting example, polyamide

[0064] In some embodiments of the methods provided herein, the indicator assembly comprises a plurality of indicators of the same or different types

[0065] In some embodiments of the methods provided herein, the indicator assembly may comprise a reading region, wherein the reading region comprises a plurality of zones, wherein at least one zone is a sample receipt zone, a marker zone, a result control zone, and a sample retaining zone. The sample receiving zone may be connected to the collection member. The marker zone may contain at least one reagent showing temperature and/or pH of the fluid sample. The result control zone can show that sufficient amount of the fluid sample has been collected. The result control zone can also contain at least one reagent for a diagnostic purpose. The sample retaining zone can retain excess fluid, for non-limiting example, where the device disclosed prevents reflux back to the collection member.

Kit

[0066] The present invention further provides a kit comprising a subject fluid sample collection device and instructions for use of the device by an end user. In one embodiment, a subject kit comprises a device which contains (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material different from the first absorbent material, wherein the collection member and the indicator assembly are in fluid communication, and wherein said indicator assembly is configured to indicate the presence of a sufficient amount of fluid sample collected by the collection member. [0067] In another embodiment, a subject kit comprises a device that contains (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material, wherein the collection member and the indicator assembly are in fluid communication, and wherein the indicator assembly has fluid-retention capability greater than the fluid-retention capability of the collection member, and the kit further comprising instructions for use of said device by an end user. In some embodiments, the first absorbent material and the second absorbent material are the same material. In some embodiments, the devices disclosed use the same material having different physical dimensions and/or properties. In yet another embodiment, a subject kit comprises a device that contains (i) a collection member comprising a first absorbent material, and (ii) an indicator assembly comprising a second absorbent material different from the first absorbent material, wherein the device is configured to permit a fluid sample to flow from the collection member to the indicator assembly, and wherein the device is configured to restrict substantially all of the flow of the fluid from the indicator assembly to the collection member.

[0068] Where desired, any subject kit may comprise a container for protecting the collection member from contamination at least prior to use. In some embodiments of the kits provided

herein, the devices in the kits comprise any combination of the elements of the devices disclosed herein In some embodiments, the container is capable of preserving the liquid sample [0069] Figure 1 shows a three dimensional view of an exemplary embodiment of disclosed fluid collection device. At one end of the device, there is a collection member 3 foi absorbing a fluid sample The collection member 3 is affixed to a base 12 The base 12 is connected to a handle 1 In the middle of handle 1 , there is a window 1 1 for observing results displayed by an indicator assembly The indicator assembly (not shown) is within the handle 1, in this embodiment A function of the base 12 is to engage the collection member 3 The engagement can be of physical means, for example, screw engagement The engagement can also be of chemical means, for example, glue or adhesive

[0070] Figure 2 shows various parts of an exemplary embodiment of disclosed fluid collection device in an exploded view. The collection member 3 has an affixing end 3 1 for engaging with the base 12 The indicator assembly can reside within an opening 13 as part of the base 12 and handle 1 The indicator assembly has two ends one end is a sample receiving zone 22 and the other end is a sample retaining zone 21 The major function of the opening 13 is to provide a housing for the indicator assembly 2 and allows the connection between the collection member 3 and the indicator assembly 2 at the same time Typically the opening 13 is connected to the window 1 1 because the indicator assembly 2 resides within the opening 13 and the window 1 1 allows observation of signal(s) from the indicator assembly [0071 ) Figure 3 shows vanous parts of an exemplary embodiment of disclosed indicator assembly in an exploded view. A covering layer 23 is typically opaque before interacting with a fluid sample In some embodiments, after collection of a fluid sample, the absorbent member will absorb the fluid sample from the collection member 3 and the covenng layer will become transparent after interacting with the fluid sample The indicator member 24 can comprise a coloring material and/or a coloring reagent In some embodiments, the coloring reagent can change color aftei interacting with the fluid sample

[0072] Figure 4A and 4B show that a color change can be observed via the window 1 1 after sufficient fluid sample has been collected. [0073] Figure 5 shows a top view of another exemplary embodiment of disclosed device The indicator assembly 2 resides within the handle 1 The base 12 is between the handle 1 and the collection member 3.

Examples

Example 1 - an exemplary embodiment having a window

[0074] As shown in Figures 1-4, one exemplary device has three major parts - a handle 1, an indicator assembly 2, and a collection member 3. In this case the handle 1 is made of opaque material and the collection member 3 is made of forming polyvinyl alcohol.

[0075] On one end, the indicator assembly 2 has a sample receiving zone 21 in connection with the collection member 3. On the other end, the indicator assembly has a sample retaining zone 22 which can reside within opening 13 of the handle 1. The handle 1 has a window 1 1 and a base 12, where the base 12 is connected with the collection member 3. [0076] The indicator assembly 2 contains a covering layer 23, an indicator member 24, and an absorbent member 25. In this case the indicator member 24 contains food coloring Brilliant Blue FCF and the absorbent member 25 is a filter paper. The absorbent member 25 is connected to the collection member 3 via the sample receiving zone 21. The sample receiving zone can be part of the absorbent member 25, resulting a "direct connection" between the absorbent member 25 and the collection member 3. In another embodiment, the sample receiving zone can be of different material and different part from the absorbent member 25, resulting an "indirect connection" between the absorbent member 25 and the collection member 3 (where the fluid sample flows from the collection member 3 to the sample receiving zone 21, and then flows from the sample receiving zone 21 to the absorbent member 25). [0077] The covering layer 23 is opaque before a fluid sample is collected. After a sufficient amount of fluid sample is collected, the fluid sample flows into the absorbent member 25 from the collection member 3. The fluid sample absorbed by the absorbent member 25 will then interact with the covering layer 23. The covering layer 23 then becomes transparent after interacting with the fluid sample and the Brilliant Blue FCF becomes visible though the window 1 1.

[0078] Accordingly, a user collecting the fluid sample can stop the collecting process after observing the Brilliant Blue FCF through the window 11, because sufficient amount of the fluid sample has been collected. [0079] In another embodiment, the covering layer 23 remains transparent always and the indicator member changes color after interacting with the sample fluid.

[0080] Because the filter paper of the absorbent member 25 uses capillary method to absorb the fluid sample and the forming polyvinyl alcohol of the collection member 3 uses hydrogen bond and Van der Waals force to absorb the fluid sample, there is no reflux of the fluid sample from the absorbent member 25 back to the collection member 3.

Example 2 - an embodiment having a transparent handle

[0081] As shown in Figure 5, another exemplary device has three majoi parts - a handle 1, an indicator assembly 2, and a collection member 3 In this case the handle is always transparent and there is no need for a window. Duπng the collection process, the fluid sample is absorbed by the collection member 3. After sufficient amount of the fluid sample has been collected, the fluid sample flows into the indicator assembly 2 via capillary method. The fluid sample interacts with an indicator member within the indicator assembly 2, resulting a color change of the indicator member Thus, a user collecting the fluid sample can stop the collecting process after observing the color change through the transparent handle 1 , because sufficient amount of the fluid sample has been collected

Example 3 - an embodiment having a pH indicator

[0082] This embodiment has all the features described in the embodiment of Example 2 In addition, the indicator assembly of this embodiment also has a pH indicator As a consequence, a use can observe whether sufficient amount of the fluid sample has been collected and observe the pH of the collected fluid sample at the same time

Example 4 - a saliva sample collection device having a substrate for amylase [0083] This embodiment has all the features described in the embodiment of Example 2. In addition, the indicator assembly of this embodiment also has a substrate for amylase. When the saliva sample flows into the indicator assembly via the collection member, amylase in the saliva sample will convert the substrate in the indicator assembly and show blue color Example 5 - a method for collecting saliva using a disclosed device

[0084] The first step is placing the collection member side of the device into a patient's mouth The patient will feel the collection member's texture change from hard to flexible [0085] The second step is observing the color change in the indicator assembly for showing that sufficient amount of the saliva sample has been collected.

[0086] The third step is removing the device from the patient's mouth The collected saliva sample can be physically squeezed out into a reservoir or test tube for subsequent diagnostic testes) There is no reflux of the saliva sample from the indicator assembly back to the collected member [0087] While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing

the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.