Gelled films, articles containing gelled films, and methods for manufacturing and using the same

Abstract

A film with a surprisingly high coat weight, comprising a plurality of particles of a water-soluble gum and a water-soluble polymer that contacts at least a portion of the surface of the particles of the water-soluble gum. An article comprising such a film on a substrate. Methods of making and using such films and articles. A dispersion useful in the manufacture of such films and articles.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the benefit of U.S. Patent Application No. 63 / 348,495, filed on June 3, 2022, and the entire content thereof is incorporated herein by reference.

[0002] Field of the Invention The field of the invention generally relates to polymer films, as well as their production and use.

[0003] Background Patent Document 1 discloses a thin - film culture plate having medium particles containing a mixture of nutrients and a gelling agent. The gelling agent is a substance such as a carbohydrate, specifically, a mixture of xanthan gum, locust bean gum, and guar gum.

[0004] Patent Document 2 discloses a dry - powder cell - culture medium containing a polymer - embedded component.

[0005] Patent Document 3 discloses a device for separately counting colonies of coliform bacteria and Escherichia coli microorganisms. This device includes a first sheet to which a first cold - water - soluble gelling agent is attached and a second sheet to which a second cold - water - soluble gelling agent is attached. Guar gum, polyacrylamide, locust bean gum, and agar are mentioned as gelling agents, and guar gum and xanthan gum alone or in combination are preferred, with guar gum being exemplified.

[0006] Patent Document 4 teaches a method for producing a fluidized agglomerated nutrient medium using a fluidized - bed agglomeration chamber. A gelling agent can be included. A binder is optionally included. PEG, polyvinylpyrrolidone, polyvinyl alcohol, polysaccharides, dextran, dextrin, maltodextrin, microcrystalline cellulose, HPMC, methylcellulose, starch, and sugars are mentioned as binders.

[0007] In Patent Document 5, a culture device for counting colonies of microorganisms is provided. A cold water-soluble gelling agent, a dry buffer system, a dry carbon dioxide generation system, and a dry oxygen removal reagent are arranged in the growth section. The gelling agents mentioned include algin, carboxymethyl cellulose, tara gum, hydroxyethyl cellulose, guar gum, locust bean gum, xanthan gum, polyacrylamide, polyurethane, and polyethylene oxide. Guar gum, locust bean gum, and xanthan gum, individually or in combination, are preferred.

[0008] Feng et al. disclose in Non-Patent Document 1 an experiment "to determine the potential enzymatic degradation of guar gum, the gelling agent used in Petrifilm (trademark) plates". This paper concludes that liquefying organisms may hydrolyze guar gum, which may have "two effects on the [counting] accuracy: (i) the liquefied area may allow the movement and growth of motile organisms, resulting in the formation of two or more colonies from a single cell, leading to an overestimation of the microbial load, and (ii) the unclear area may obscure other colonies, leading to a potential underestimation".

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Non-Patent Documents

[0010]

Non-Patent Document 1

[0011] Detailed Description of Exemplary Embodiments In the present application, terms such as "a", "an", and "the" are not intended to refer only to singular entities, but include general classes for which specific examples may be used for illustration. The terms "a", "an", and "the" are used interchangeably with the expressions "at least one" and "one or more". The expressions "at least one of" and "including at least one of" with a list refer to any one of the items in the list and any combination of two or more items in the list.

[0012] Terms such as "general", "generally", "often", "frequent", and "frequently" are used to refer to features typically used in the present invention, but are not intended to imply that the features so described were known or common prior to the present disclosure, unless otherwise indicated.

[0013] The use of "or" means "and / or" unless specifically stated otherwise.

[0014] The uses of "comprise", "comprises", "comprising", "include", "includes", and "including" are interchangeable and are not intended to be limiting. Further, when the term "comprising" is used in the description of one or more embodiments, those skilled in the art will understand that in some specific examples, the singular or plural embodiments may alternatively be described using the expressions "consisting essentially of" and / or "consisting of".

[0015] As used herein, the term "about" refers to a variation of ±10% from a nominal value. It should be understood that such variations are always included in any given value presented herein, whether or not such variations are specifically recited.

[0016] Any range given either in absolute terms or in approximate terms is intended to cover both, and any definitions used herein are intended to clarify rather than limit. Numerical ranges and parameters defining the broad scope of the invention are approximations, although the numerical values recited in specific examples are reported as accurately as possible. Further, all ranges disclosed herein are to be understood to encompass any and all sub-ranges subsumed therein (including all fractional and integral values).

[0017] "PEO" refers to a water-soluble organic polymer having repeating units of the chemical formula -OCH2CH2-. PEO as used herein refers simply to the chemical structure of the polymer and includes not only polymers known as polyethylene oxide but also polymers known as poly(ethylene glycol) or PEG having repeating units of the same chemical formula as polyethylene oxide and which may have different end groups, although not necessarily so. PEO may have various end groups including, but not limited to, hydroxy and alkoxy. When one or more of the end groups are alkoxy, the alkoxy may be C1-C4 alkoxy or generally C1 alkoxy. A mixture of end groups is also possible. PEO is most commonly linear, although minor branching is possible.

[0018] "PVP" refers to poly(vinylpyrrolidone), a water-soluble polymer.

[0019] "Total coat weight" refers to the coat weight (g / 24 in 2 ) of a dry film containing a water-soluble gum and a water-soluble polymer, prepared according to the method disclosed herein.

[0020] Unless otherwise specified, all particle sizes in this disclosure and the appended claims refer to the average particle size determined by light scattering.

[0021] Unless otherwise specified, all pH values in this disclosure and the appended claims refer to the pH value measured at about 20 °C.

[0022] Unless otherwise specified, the molecular weight of all polymer materials in this disclosure and the appended claims is reported in daltons (D) or kilodaltons (kD) as appropriate, and is the weight-average molecular weight determined by gel permeation chromatography in tetrahydrofuran by comparison with a narrow poly(styrene) standard.

[0023] Thin film culture devices, such as those disclosed in, for example, U.S. Patent No. 5,869,321, U.S. Patent No. 9,988,600, and U.S. Patent Application Publication No. 2020 / 001943, typically include a substrate having a film incorporating a water-soluble gum, such as guar gum, xanthan gum, or locust bean gum. These gums are commercially available in the form of particles that dissolve in water to produce a viscous solution. Forming a film of a water-soluble gum on a substrate is difficult, especially in a manufacturing environment where it is necessary to consistently and repeatedly form films having precisely defined coating weights. Current methods of forming films of gums involve powder coating, a high-cost process that requires very specialized equipment and demanding operating conditions, especially when carried out on a commercial scale.

[0024] Prior to the advancements described herein, solvent coating (as used herein, including coatings from any dispersion of solids in a liquid and not limited to coatings from solutions of solutes dissolved in a liquid), which is generally easy to perform repeatedly on a commercial scale, was considered unacceptable. Prior to the advancements described in the present disclosure, to coat an aqueous solution of a high molecular weight gum with a low gum concentration to a sufficient thickness, a large amount of aqueous coating solution was required, which meant that a large amount of water had to be removed to form a dry film. The removal of a large amount of water required a large amount of heat and time, and thus, the manufacturing was slow, or an excessive amount of energy was required for heating, or both, resulting in exorbitant costs. At higher concentrations where less water can be used, the gum raises the viscosity of the coating solution to a level where coating is impossible.

[0025] Thus, the problem to be solved can be stated as a method of providing a film comprising a gum to be solvent coated. The problem can alternatively be stated as a method of preparing a concentrated dispersion of a gum that is sufficiently low in viscosity to be usable in a solvent coating process.

[0026] Film Briefly stated, the solution to one or more of these problems and other problems lies in a film comprising a plurality of water-soluble gum particles and a water-soluble polymer in contact with at least a portion of the surface of the water-soluble gum particles, as well as a method of manufacturing the film, an article comprising the film, and a method of using the film.

[0027] Any water-soluble gum can be used, regardless of whether the gum swells upon contact with water. Without wishing to be bound by any particular theory, the gum is capable of swelling when contacted with water and may gel (for example, when the amount of water used is insufficient to dissolve all or part of the gum). Most commonly, the gum is a natural gum, although synthetic gums may also be used. The most commonly used gums are xanthan gum, locust bean gum, and guar gum, and mixtures thereof. Guar gum is most commonly used.

[0028] The gum is in particulate form. Gum particles are commercially available under the trade names of, for example, MEYPROGAT (Danisco, Switzerland) and VISCOGUM (Cargill, Minnesota, USA). In principle, the particle size of the gum is limited only by its ability to form a film, for example, by the methods described herein. In some embodiments, the particle size can be from about 25 to about 200 microns. In further embodiments, the particle size can be from about 25 to about 200 microns, from about 50 to about 175 microns, from about 75 to about 150 microns, or from about 100 to about 125 microns.

[0029] In principle, any water-soluble polymer can be used, but most commonly, the water-soluble polymer is a synthetic polymer. In some cases, it is advantageous for the water-soluble polymer to also be soluble in a solution of water and a water-soluble (or more preferably, water-miscible) organic solvent, since such a solution (i.e., a solution of a water-soluble polymer in water and a water-soluble, especially water-miscible, organic solvent) is more convenient to use in the context of the present disclosure than a solution of the water-soluble polymer in water alone. For this reason, most water-soluble polymers used are water-soluble polymers that are also soluble in a mixture of water and at least one water-soluble, especially water-miscible, organic solvent. The water-miscible organic solvents mentioned can be selected from the group consisting of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether, and acetone. More generally, the water-miscible organic solvent is selected from the group consisting of isopropanol, ethanol, and methanol. Most often, the water-miscible organic solvent mentioned in this section is isopropanol. However, it should be noted that the water-soluble polymer does not need to be soluble in a water-soluble or water-miscible organic solvent, and even if the water-soluble polymer is also soluble in a water-soluble or water-miscible organic solvent, it is not necessary to use a water-soluble or water-miscible organic solvent. On the other hand, even if the polymer is water-soluble, a water-soluble or water-miscible organic solvent may be used and water may not be used.

[0030] Regarding the chemical identity of the water-soluble polymer, it can be selected from a wide variety of polymers including polymeric surfactants, polyelectrolytes such as polyanions, polycations, and polyzwitterions, and polar polymers. The water-soluble polymer can be selected from PVP and PEO, and PEO is used somewhat more commonly.

[0031] Water-soluble polymers and gum particles can, in principle, be in any ratio in the film. In some embodiments, the ratio (w / w) of the polymer to the gum is from about 1:200 or more to about 2:1 or less, optionally from about 1:100 or more to about 1:1 or less, for example from about 1:50 or more to about 1.5:1 or less, or from about 1:100 or more to about 1:1 or less, or from about 1:40 or more to about 1:1 or less. Water-soluble polymers of various molecular weights can be used. The molecular weight is mainly determined by factors related to the film manufacturing method, which will be detailed below.

[0032] In some embodiments, the water-soluble polymer and the gum particles can be in any ratio in the film. For example, the ratio (w / w) of the polymer to the gum is from about 1:200 to about 2:1, from about 1:100 to about 1:1, from about 1:50 to about 1.5:1, from about 1:100 to about 1:1 or from about 1:40 to about 1:1.

[0033] The water-soluble polymer contacts at least the surface of the gum particles. Depending on the ratio of the water-soluble polymer to the gum particles, the gum particles can be partially or completely entrained in the matrix of the water-soluble polymer. For example, if at least a portion of the gum particles is completely surrounded by the matrix, the gum particles can be partially entrained in the water-soluble polymer matrix. If more than half of the gum particles, and in some cases substantially all of the gum particles (i.e., about 80% or more, about 85% or more, about 90% or more, about 95% or more or even about 99% or more) are completely surrounded by the matrix, the gum particles can be completely entrained in the matrix. The gum particles can be entrained in the matrix from about 80% to about 99%, from about 85% to about 95%, or about 90%.

[0034] The water-soluble polymer may be a partial or complete coating on the surface of the gum particles (e.g., water-soluble coated gum particles). The particles may optionally be partially or completely entrained in the matrix of the water-soluble polymer. The water-soluble polymer need not be present as a matrix, as at least some of the desired results can be achieved when the water-soluble polymer simply contacts at least a portion of the surface of the gum particles that are insoluble in the water-organic solvent mixture or organic solvent.

[0035] It is possible to include additional components in the film. For example, when the film is used as part of a culture device, one or more of nutrients (for one or more microorganisms), dyes, in particular indicator compounds such as redox dyes, and selection agents such as antibiotics can be included.

[0036] Article An article comprising any of the above-described films may include a substrate including a first major surface and any of the above-described films contacting at least a portion of the first major surface of the substrate. Any suitable substrate can be used as long as the film is laminated to the substrate well enough to maintain its integrity until used. The substrate can be plastic, metal, or glass. Plastic is the most common.

[0037] One or more portions of the first major surface that contact the film can be the outermost layer of one or more layers of the substrate and do not necessarily have an adhesive on the first major surface of the substrate. This is often because the film can be laminated to the substrate during the coating process without the need for an adhesive on the film. In other cases, one or more portions of the first major surface that contact the film may include an adhesive on the first major surface of the substrate. For the purposes of the present disclosure and the appended claims, it should be noted that even if an adhesive layer such as an adhesive film is present on all or part of the first major surface of the substrate, the first major surface is considered to be in contact with the film. This is because in this case, the adhesive layer or film is considered to be part of the first major surface of the substrate. While it may be advantageous to omit the adhesive when it is not needed as it can lower the cost of the article or make it easier to manufacture without an adhesive, in many cases the adhesive is used to improve the durability or shelf life of the article, ensure a complete and reproducible adhesion between the film and the first major surface, or for other considerations.

[0038] When the article is a cell culture device such as a thin film culture device, the film can be disposed within the growth compartment of the thin film culture device.

[0039] Manufacturing method The film can be manufactured by any suitable method. For example, a plurality of water-soluble gum particles are dispersed in water, at least one water-soluble organic solvent, particularly at least one water-miscible organic solvent, or a mixture of water and at least one water-soluble organic solvent. The water-soluble organic solvent is, in most cases, the one discussed herein with respect to water-soluble polymers. Most commonly, when using water and at least a water-soluble organic solvent, this is a single-phase mixture, but if at least one water-soluble organic solvent is immiscible with water, a two-phase mixture may be used. A mixed solvent system of water and at least one water-soluble organic solvent is generally required when at least one water-soluble polymer does not dissolve well in a water-free system. If at least one water-soluble polymer dissolves in the organic solvent alone, the organic solvent alone can be used, but even in this case, it may be desirable to use a mixed solvent system to reduce the amount of organic solvent used in the process.

[0040] In some embodiments, the solids percentage of the plurality of water-soluble gum particles is from about 5 wt% to about 60 wt%, such as about 5 wt% or more, about 10 wt% or more, about 20 wt% or more, about 15 wt% or more, about 30 wt% or more, or about 40 wt% or more (regardless of the solvent system used). In further embodiments, the solids percentage of the plurality of water-soluble gum particles is about 50 wt% or less, about 40 wt% or less, about 30 wt% or less, about 25 wt% or less, about 20 wt% or less, about 15 wt% or less, or even about 10 wt% or less.

[0041] In some embodiments, the solids percentage of the plurality of water-soluble gum particles is about 5 wt% to about 50 wt%, about 5 wt%, about 10 wt%, about 15 wt%, about 20 wt%, about 25 wt%, about 30 wt%, about 35 wt%, about 40 wt%, about 45 wt%, or about 50 wt%.

[0042] Normally, at least one water-soluble polymer that is also soluble in a mixture of water and an organic solvent and, in some cases, soluble in the organic solvent alone is added to the dispersion in this case and may be dissolved in the dispersion. The addition of the water-soluble polymer and the addition of the gum particles can be sequential in any order, or the water-soluble polymer and the gum particles can be added simultaneously. If any additional agent is included in the film, this agent can also be added to the dispersion as a dissolved solute or dispersed particles.

[0043] The organic solvent is at least partially dissolved in water. This process may be a single-phase process in which no other solvent phase is present. In some cases, it may be possible to carry out the process in a multiphase system such as an emulsion system.

[0044] In some cases, it may be beneficial to stir the resulting dispersion of the dissolved water-soluble polymer and the dispersed gum particles for, for example, about 1 minute to about 1 hour to disperse any aggregated particles. In some embodiments, the resulting dispersion of the dissolved water-soluble polymer and the dispersed gum particles is stirred for about 2 minutes to about 55 minutes, about 3 minutes to about 50 minutes, about 4 minutes to about 45 minutes, about 5 minutes to about 40 minutes, about 10 minutes to about 35 minutes, about 15 minutes to about 30 minutes, or about 20 minutes to about 25 minutes. When stirring is carried out, it may be done by hand or using standard laboratory equipment such as a stirrer, roller, or shaker. Since aggregation does not always occur, it is not always necessary to stir the dispersion.

[0045] The ratio of the water-soluble polymer to the gum particles is the same as the ratio in the resulting film. This ratio is discussed herein with respect to the film.

[0046] Water-soluble polymers of any suitable concentration can be used. The concentration is limited by the solubility of the water-soluble polymer in a mixture of water and an organic solvent or in the organic solvent, or, if the viscosity is excessively high, by the viscosity of the dispersion or solution of the water-soluble polymer since processing of the resulting liquid or coating on a substrate becomes difficult, or is limited by a combination of solubility and viscosity. The molecular weight of the water-soluble polymer can also vary. Without wishing to be bound by any particular theory, as the molecular weight of the water-soluble polymer increases, the solution viscosity at the same polymer concentration (mass / mass) increases. To what extent this holds true depends on the nature of the polymer. For this reason, although the molecular weight and concentration of the water-soluble polymer can vary, the combination of the molecular weight and concentration of the water-soluble polymer is selected such that the water-soluble polymer dissolves. Examples of suitable molecular weights include from about 100 kD to about 7000 kD. For example, a molecular weight in the range of about 100 kD to about 7000 kD can be used. In some embodiments, the molecular weight includes about 100 kD or more, about 1000 kD or more, about 2000 kD or more, about 4000 kD or more, or about 5000 kD or more can be used. Other exemplary molecular weights are about 7000 kD or less, about 5000 kD or less, about 4000 kD or less, about 2000 kD or less, and about 1000 kD or less. However, these molecular weights are merely illustrative, and other molecular weights can be used as long as the final viscosity is acceptable.

[0047] The concentration of the water-soluble polymer is from about 0.25 wt% to about 20 wt%. For example, the concentration of the water-soluble polymer can be in the range of about 0.25 wt% to about 20 wt%. In some embodiments, the concentration can be about 0.5 wt% or more, about 1 wt% or more, about 5 wt% or more, about 10 wt% or more, about 15 wt% or more, about 20 wt% or less, about 15 wt% or less, about 12.5 wt% or less, about 10 wt% or less, or about 5 wt% or less.

[0048] In some embodiments, the molecular weight of the water-soluble polymer can be from about 100 kD to about 7000 kD. In some embodiments, the molecular weight can be in the range of about 1000 kD to about 7000 kD, 2000 kD to about 5000 kD, 3000 kD to about 5000 kD, about 500 kD, about 1000 kD, about 2000 kD, about 3000 kD, about 4000 kD or about 5000 kD.

[0049] In some embodiments, the concentration of the water-soluble polymer is from about 0.25 wt% to about 20 wt%. In further embodiments, the concentration is about 0.25 wt%, about 0.5 wt%, about 1 wt%, about 5 wt%, about 10 wt%, about 12.5 wt%, about 15 wt% or about 20 wt%.

[0050] The resulting dispersion can subsequently be solvent-coated onto a substrate, such as plastic, glass, etc. Any suitable solvent coating method can be used depending on the desired characteristics of the product. Examples of coating methods include die coating, knife coating, solvent casting and spin coating. Solvent coating is possible because the addition of gum particles at a suitable concentration does not increase the viscosity of the dispersion.

[0051] The viscosity of the dispersion is from about 200 cP to about 10000 cP. For example, the viscosity of the dispersion can be from about 200 cP to about 10000 cP. In some embodiments, the viscosity of the dispersion is from about 1000 cP to about 10000 cP, 200 cP to about 1000 cP, 1000 cP to about 5000 cP, or 4000 cP to about 10000 cP.

[0052] In some embodiments, the resulting dispersion has a viscosity that facilitates coating of the dispersion onto the substrate. For example, the dispersion is pumpable, i.e., the dispersion has a viscosity such that the dispersion can be supplied through a nozzle.

[0053] After coating, the article can be dried to remove water and organic solvents. The drying process can be carried out to a certain mass, but it is not always necessary, depending on the desired properties of the final product.

[0054] The total coat weight of the dry film can be from about 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to about 2500 mg / 154.84 cm 2 (2500 mg / 24 in 2 ) In some embodiments, the total coat weight is from about 600 mg / 154.84 cm 2 (600 mg / 24 in 2 ) to about 2400 mg / 154.84 cm 2 (2400 mg / 24 in 2 ) from about 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to about 2400 mg / 154.84 cm 2 (2400 mg / 24 in 2 ) from about 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to about 2000 mg / 154.84 cm 2 (2000 mg / 24 in 2 ) from about 800 mg / 154.84 cm 2 (800 mg / 24 in 2 ) to about 2200 mg / 154.84 cm 2 (2200 mg / 24 in 2 ) from about 900 mg / 154.84 cm 2 (900 mg / 24 in 2 ) to about 2100 mg / 154.84 cm 2 (2100 mg / 24 in 2 ) from about 1000 mg / 154.84 cm 2 (1000 mg / 24 in 2 ) to about 2000 mg / 154.84 cm 2 (2000 mg / 24 in 2 ) from about 700 mg / 154.84 cm 2 (700 mg / 24 in 2) to approximately 16000 mg / 154.84 cm 2 (16000 mg / 24 in 2 )、 approximately 1100 mg / 154.84 cm 2 (1100 mg / 24 in 2 ) to approximately 1900 mg / 154.84 cm 2 (1900 mg / 24 in 2 )、 approximately 1200 mg / 154.84 cm 2 (1200 mg / 24 in 2 ) to approximately 1800 mg / 154.84 cm 2 (1800 mg / 24 in 2 )、 approximately 1300 mg / 154.84 cm 2 (1300 mg / 24 in 2 ) to approximately 1700 mg / 154.84 cm 2 (1700 mg / 24 in 2 )、 approximately 1400 mg / 154.84 cm 2 (1400 mg / 24 in 2 ) to approximately 1600 mg / 24 in 2 ) or approximately 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to approximately 1000 mg / 154.84 cm 2 (1000 mg / 24 in 2 ) is.

[0055] In some embodiments, the present invention is a film comprising a plurality of particles of a water-soluble gum and a water-soluble polymer in contact with at least a portion of the surface of the water-soluble gum particles, approximately 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to approximately 2500 mg / 154.84 cm 2 (2500 mg / 24 in 2 ) having a total coat weight in the range of, relating to a film.

[0056] In a further embodiment, the present invention is a film comprising a plurality of particles of guar gum and a water-soluble polymer in contact with at least a portion of the surface of the guar gum particles, approximately 500 mg / 154.84 cm 2 (500 mg / 24 in 2) to approximately 2500 mg / 154.84 cm 2 (2500 mg / 24 in 2 ) or approximately 700 mg / 154.84 cm 2 (700 mg / 24 in 2 to approximately 2400 mg / 154.84 cm 2 (2400 mg / 24 in 2 ) or approximately 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to approximately 2000 mg / 154.84 cm 2 (2000 mg / 24 in 2 ) having a total coat weight in the range of

[0057] In a further embodiment, the present invention is a film comprising a plurality of particles of guar gum and PVP in contact with at least a portion of the surface of the guar gum particles, approximately 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to approximately 2500 mg / 154.84 cm 2 (2500 mg / 24 in 2 ) or approximately 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to approximately 2400 mg / 154.84 cm 2 (2400 mg / 24 in 2 ) or approximately 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to approximately 2000 mg / 154.84 cm 2 (2000 mg / 24 in 2 ) having a total coat weight in the range of

[0058] In a further embodiment, the present invention is a film comprising a plurality of particles of guar gum and PEO in contact with at least a portion of the surface of the guar gum particles, approximately 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to approximately 1500 mg / 154.84 cm 2 (1500 mg / 24 in 2 ) or approximately 500 mg / 154.84 cm2 (500 mg / 24 in 2 ) to approximately 1000 mg / 154.84 cm 2 (1000 mg / 24 in 2 ) having a total coat weight in the range of. Regarding the film.

[0059] While not wishing to be bound by any particular theory, one advantage of the present invention is the prevention of the phenomenon of gel blocking in a substrate or film coated with a dispersion. Gel blocking is a phenomenon that occurs when the top layer of a substrate or film coated with a dispersion swells or gels completely upon rehydration, thereby causing a gel block in the top layer and preventing complete rehydration of the substrate or film coated with the dispersion.

[0060] Another advantage of the present invention is that the resulting film produced by the method encompassed by the present invention can achieve a high total coat weight while maintaining optimal swelling or gelling properties of the dispersed gum particles.

[0061] Usage method When the article is a cell culture device such as a thin film culture device, it can be manufactured by a prior art method and used in the same manner as a conventional cell culture device lacking a water-soluble polymer. The water solubility of the water-soluble polymer means that when the film portion of the cell culture device comes into contact with an aqueous sample containing one or more microorganisms and an inoculated article is formed, the water-soluble polymer dissolves and it becomes possible to hydrate the gum particles with the water in the aqueous sample.

[0062] The inoculated article can then be incubated for a period of time sufficient for the microorganism to undergo at least one growth cycle, and the presence of the microorganism is detected. The incubation time can vary widely depending on the type of microorganism and the temperature. Exemplary incubation times are disclosed, for example, in U.S. Patent No. 5,869,321, U.S. Patent No. 9,988,600, and U.S. Patent Application Publication No. 2020 / 001943. After incubation, one or more microorganisms can be detected or counted by any suitable means. For example, the Petrifilm(™) Plate Reader Advanced (available from 3M Company, St. Paul, Minnesota) is a commercially available device for counting thin film culture plates such as those commercially available under the trade name Petrifilm(™) (also from 3M Company).

[0063] Examples Material BACTO Tryptic Soy Broth (TSB) was obtained from Becton, Dickinson and Company, Franklin Lakes, New Jersey. Butterfield’s Buffer was obtained from 3M Company, Maplewood, Minnesota. 2,3,5-Triphenyltetrazolium chloride (TTC) was obtained from MilliporeSigma Company, St. Louis, Missouri. Isopropanol (IPA) was obtained from VWR International, Radnor, Pennsylvania.

[0064] Polyvinylpyrrolidone (PVP), K90 grade, was obtained from Ashland Incorporated, Wilmington, Delaware.

[0065] POLYOX WSR 301 polyethylene oxide (PEO) polymer (4000000 g / mol), POLYOX WSR 303 polyethylene oxide (PEO) polymer (7000000 g / mol), POLYOX WSR N12K polyethylene oxide (PEO) polymer (1000000 g / mol), and POLYOX WSR N60K polyethylene oxide (PEO) polymer (2000000 g / mol) were obtained from DuPont, Wilmington, Delaware.

[0066] Guar gum (Meyprogat 150) was obtained from Danisco, Copenhagen, Denmark. The guar gum was sterilized with ethylene oxide and carefully aerated to remove residual sterilizing agents.

[0067] Unless otherwise specified, water was obtained from a MILLI-Q water purification system (EMD Millipore, Billerica, Massachusetts).

[0068] Preparation Example 1 . Preparation of Inoculum The bacterial strains Escherichia coli (ATCC 25922), Escherichia coli (ATCC 8739), Escherichia coli (ATCC 51813), Staphylococcus aureus (ATCC 25923), Staphylococcus aureus (ATCC 6538), Acinetobacter spp. (ATCC 51819), and Chryseobacterium shigense (ATCC 51823) were obtained from Microbiologics, Incorporated (St. Cloud, Minnesota) or VWR International and individually incubated overnight at 37°C and 200 rpm in tryptic soy broth (TSB) in an INNOVA 44 incubator (New Brunswick Scientific, Enfield, Connecticut). Each inoculum was prepared by serially diluting a single culture sample in Butterfield’s Buffer. Each culture sample was diluted to obtain a final concentration of approximately 50 - 250 colony forming units (cfu) per mL of inoculum.

[0069] Examples 1 to 24 . Dispersion formulations of guar gum, PVP (K90), and isopropanol Twenty-four individual formulations were prepared using various amounts (in grams) of the components listed in Table 1. For each formulation, isopropanol (IPA) and PVP (K90) were added to a glass bottle (4 ounces) and mixed with a magnetic stir bar until the PVP was dissolved. Then, guar gum was added to the bottle and the mixture was stirred with a magnetic stir bar for 30 minutes, after which the capped bottle was placed on a laboratory roller for further mixing. Mixing using the roller was continued for at least 1 hour to remove any large visible aggregates.

[0070] [Table 1]

[0071] Examples 25 to 34 . Dispersion formulations of guar gum, POLYOX WSR Nl2K PEO polymer, isopropanol and water Ten individual formulations were prepared using various amounts (in grams) of the components listed in Table 2. For each formulation, isopropanol and POLYOX WSR Nl2K polyethylene oxide polymer were added to a glass bottle (16 ounces) and mixed with a magnetic stir bar until the polymer was dispersed. Water was added to the bottle and the contents were mixed with a magnetic stir bar for 1 hour. If the polymer was not completely dissolved, the capped bottle was placed on a laboratory roller until the polymer dissolved. Then, guar gum was added to the bottle and after first shaking the bottle by hand, the capped bottle was placed on a laboratory roller and mixed for at least an additional 1 hour. Mixing using the roller was continued for at least 1 hour to remove any large visible aggregates.

[0072]

Table 2

[0073] Examples 35 to 36 . Dispersion formulations of guar gum, POLYOX WSR N60K PEO polymer, isopropanol and water The same procedure as reported in Examples 25 - 34 was followed, except that the POLYOX WSR Nl2K polyethylene oxide polymer in the formulation was replaced with POLYOX N60K polyethylene oxide polymer. Two formulations were prepared using various amounts (in grams) of the components listed in Table 3.

[0074]

Table 3

[0075] Examples 37 to 38 . Dispersion formulations of guar gum, POLYOX WSR 301 PEO polymer, isopropanol and water The same procedure as reported in Examples 25 - 34 was followed, except that the complex POLYOX WSR Nl2K polyethylene oxide polymer was replaced with POLYOX WSR 301 polyethylene oxide polymer. Two formulations were prepared using various amounts (in grams) of the components listed in Table 4.

[0076]

Table 4

[0077] Examples 39 to 42 . Dispersion formulations of guar gum, POLYOX WSR 303 PEO polymer, TSB, isopropanol and water Four individual formulations were prepared using various amounts (in grams) of the components listed in Table 5. For each formulation, isopropanol and POLYOX WSR 303 polyethylene oxide polymer were added to a glass bottle (16 ounces) and mixed with a magnetic stir bar until the polymer was dispersed. Water was added to the bottle and the contents were mixed with an IKA Eurostar 60 overhead stirrer (IKA Works, Wilmington, North Carolina) equipped with a four - blade impeller until the polymer dissolved. After adding the TSB powder to the solution, the mixture was stirred with the overhead stirrer until the color and viscosity of the dispersion were uniform. Then, guar gum was added to the bottle and the contents were stirred with the overhead stirrer until the color and viscosity of the dispersion were uniform.

[0078]

Table 5

[0079] Examples 43 to 53 . Films prepared by coating the formulations of Examples 1 - 12 onto a PET substrate Twelve separate films were prepared by coating a single formulation selected from the formulations of Examples 1 to 12 on the surface of a polyethylene terephthalate (PET) film substrate (thickness 3.8 mils (0.1 mm)). Each PET substrate sample was coated using a 14 mil (0.35 mm) wet gap and a notch bar. The coated films were placed in an oven set at 85 °C for 12 minutes. The total coat weight (g / 24 in 2 ) of the resulting dry films was determined, and the coat weights of the individual components (PVP and guar gum) of each film were also calculated based on the weights of the individual components (PVP and guar gum) in the coating formulation. The results are reported in Table 6.

[0080]

Table 6

[0081] Examples 55 to 66 . Films prepared by coating the formulations of Examples 13 to 24 on a BOPP substrate A biaxially oriented polypropylene (BOPP) film (thickness 1.6 mils (0.04 mm)) with a pressure-sensitive adhesive [isooctyl acrylate / acrylic acid (weight ratio 98 / 2) containing a TTC indicator] laminated on one side was prepared according to the procedure described in Example 4 of U.S. Patent No. 5,409,838 (Wickert).

[0082] Twelve separate films were prepared by coating a single formulation selected from the formulations of Examples 13 to 24 on the adhesive surface of a BOPP film substrate. Each BOPP substrate sample was coated using a 14 mil (0.35 mm) wet gap and a notch bar. The coated films were placed in an oven set at 85 °C for 12 minutes. The total coat weight (g / 24 in 2 ) of the resulting dry films was determined, and the coat weights of the individual components (PVP and guar gum) of each film were also calculated based on the weights of the corresponding individual components (PVP and guar gum) in the coating formulation. The results are reported in Table 7.

[0083]

Table 7

[0084] Examples 67 to 76 . Films prepared by coating the formulations of Examples 25 - 34 onto a PET substrate Ten separate films were prepared by coating a single formulation selected from the formulations of Examples 25 - 34 onto the surface of a PET film substrate (3.8 mils (0.1 mm) thick). Each PET substrate sample was coated using a 14 - mil (0.35 mm) wet gap and a notch bar. The coated films were placed in an oven set at 85°C for 12 minutes. The total coat weight (g / 24 in 2 ) of the resulting dry films was determined, and the coat weights of the individual components (PEO and guar gum) of each film were also calculated based on the weights of the individual components (PEO and guar gum) in the corresponding coating formulation. The results are reported in Table 8.

[0085]

Table 8

[0086] Examples 77 to 78 . Films prepared by coating the formulations of Examples 35 - 36 onto a PET substrate Two separate films were prepared by coating a single formulation selected from the formulations of Examples 35 and 36 onto a PET film substrate (3.8 mils (0.1 mm) thick). Each PET substrate sample was coated using a 14 - mil (0.35 mm) wet gap and a notch bar. The coated films were placed in an oven set at 85°C for 12 minutes. The total coat weight (g / 24 in 2 ) of the resulting dry films was determined, and the coat weights of the individual components (PEO and guar gum) of each film were also calculated based on the weights of the individual components (PEO and guar gum) in the corresponding coating formulation. The results are reported in Table 9.

[0087]

Table 9

[0088] Examples 79 to 80 . Films prepared by coating the formulations of Examples 37-38 onto a PET substrate Two separate films were prepared by coating a single formulation selected from the formulations of Examples 37 and 38 onto a PET film substrate (thickness 3.8 mils (0.1 mm)). Each PET substrate sample was coated using a 14-mil (0.35 mm) wet gap and a notch bar. The coated films were placed in an oven set at 85 °C for 12 minutes. The total coat weight (g / 24 in 2 ) of the resulting dry films was determined, and the coat weights of the individual components (PEO and guar gum) of each film were also calculated based on the weights of the individual components (PEO and guar gum) in the corresponding coating formulation. The results are reported in Table 10.

[0089]

Table 10

[0090] Examples 81 to 84 . Films prepared by coating the formulations of Examples 39-42 onto a BOPP substrate Four separate films were prepared by coating a single formulation selected from the formulations of Examples 39-42 onto the adhesive surface of the BOPP film substrates described in Examples 55-66. Each BOPP substrate sample was coated using a 14-mil (0.35 mm) wet gap and a notch bar. The coated films were placed in an oven set at 85 °C for 12 minutes. The total coat weight (g / 24 in 2was determined, and the coat weights of the individual components (PEO, guar gum, and TSB) of each film were also calculated based on the weights of the individual components (PEO, guar gum, and TSB) in the corresponding coating formulations. The results are reported in Table 11.

[0091]

Table 11

[0092] Example 85 . Preparation of Thin-Film Culture Devices The coated BOPP film substrates of Examples 81 to 84 were cut into sections measuring 76 mm in width × 102 mm in length. The cover sheet (76 mm in width × 102 mm in length) was peeled off from a PETRIFILM Aerobic Count Plate (obtained from 3M Corporation, Maplewood, Minnesota). The thin-film culture device was assembled by attaching the cover sheet (like a hinge) along one side (76-mm side) of the coated film substrate to the coated film using double-sided adhesive tape. For each device, the cover sheet and the substrate were oriented such that their ends were aligned and the guar-coated surface of the cover sheet faced the coated surface of the coated film substrate.

[0093] Example 86 . Colony Counting Method Using the Device of Example 85 The thin-film culture device of completed Example 85 was inoculated with an inoculum of any one of Escherichia coli (ATCC 25922), Escherichia coli (ATCC 8739), Escherichia coli (ATCC 51813), Staphylococcus aureus (ATCC 25923), Staphylococcus aureus (ATCC 6538), Acinetobacter species (ATCC 51819), or Chryseobacterium shigense (ATCC 51823). The device was placed on a flat horizontal surface. The cover sheet of each device was lifted, and 1 mL of a single inoculum (i.e., the final dilution described in Preparation Example 1) was carefully added as a single application by pipette to a compact area in the center of the coated substrate. The cover sheet was gently returned to its original position. A 3M PETRIFILM Spreader (obtained from 3M Company) was applied to the outer surface of the cover sheet to spread the inoculum so as to form a circular area with a diameter of about 2 inches (5.1 cm). Each device was incubated at 32 °C for 48 hours. At the end of the incubation period, the devices were evaluated for bacterial colony formation. Red-colored dot-like colonies scattered over the entire surface of each device were counted by visual inspection. The results are shown in Table 12 as the average number of colonies (cfu / mL) for two tests (n = 2). Also, as a control, a 3M PETRIFILM Aerobic Count Plate was used to analyze the inoculum according to the manufacturer's instructions. The average number of colonies (cfu / mL) using the control plates (n = 2) is reported in Table 12.

[0094]

Table 12

[0095] List of Embodiments The following is a non-limiting list of embodiments: 1. A film comprising a plurality of particles of a water-soluble gum and a water-soluble polymer that contacts at least a portion of the surface of the particles of the water-soluble gum, having a total coat weight in the range of about 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to about 2500 mg / 154.84 cm 2 (2500 mg / 24 in 2 ), or about 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to about 2400 mg / 154.84 cm 2 (2400 mg / 24 in 2 ), or about 700 mg / 154.84 cm 2 (700 mg / 24 in 2 ) to about 2000 mg / 154.84 cm 2 (2000 mg / 24 in 2 ). 2. The film according to embodiment 1, wherein the water-soluble polymer is also soluble in a solution of water and a water-soluble organic solvent, the water-soluble organic solvent is optionally selected from the group consisting of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether, and acetone, the water-soluble organic solvent is further optionally selected from the group consisting of isopropanol, ethanol, and methanol, and further optionally, the water-soluble organic solvent is isopropyl alcohol. 3. The film according to embodiment 1 or 2, wherein the polymer is selected from PEO and PVP. 4. The film according to any one of embodiments 1 to 3, wherein the water-soluble gum is capable of gelling when contacted with cold water. 5. The film according to any one of embodiments 1 to 4, wherein the gum is selected from guar gum, locust bean gum, and xanthan gum, and optionally, the gum is guar gum. 6. The film according to any one of embodiments 1 to 5, wherein at least a portion of the particles of the water-soluble gum is completely entrained by the water-soluble polymer. 7. The film according to any one of Embodiments 1 to 6, wherein the ratio of the polymer to the gum is from about 1:200 or more to about 2:1 or less, optionally from about 1:100 or more to about 1:1 or less. 8. An article comprising a substrate and the film according to any one of Embodiments 1 to 7, which is in contact with at least a part of the first major surface of the substrate, wherein the substrate comprises at least one of plastic, metal or glass, and preferably, the substrate comprises plastic. 9. The article according to Embodiment 8, wherein the portion of the first major surface of the substrate in contact with the film does not have an adhesive. 10. The article according to Embodiment 8 or 9, wherein the film is disposed in the growth compartment of a thin film culture device. 11. The article according to any one of Embodiments 8 to 10, wherein the film further comprises at least one nutrient for promoting the growth of at least one microorganism. 12. The article according to any one of Embodiments 8 to 11, wherein the film further comprises at least one dye, optionally at least one redox dye. 13. A method for manufacturing an article, dispersing particles of at least one water-soluble gum in a liquid containing water, at least one water-soluble organic solvent, or a mixture of water and at least one organic solvent, and dissolving at least one water-soluble polymer in a liquid containing water, at least one water-soluble organic solvent, or a mixture of water and at least one organic solvent to form a dispersion of the particles of at least one water-soluble gum and at least one water-soluble polymer in the liquid to form a dispersion, solvent coating the dispersion on the substrate to form a film on the substrate and comprising, wherein the article is optionally the article according to any one of Embodiments 8 to 12, and the film is optionally the film according to any one of Embodiments 1 to 7. Method. 14. The method according to Embodiment 13, further comprising drying the article to a certain mass. 15. The method according to embodiment 13 or 14, wherein at least one organic solvent comprises one or more of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether, and acetone, or is optionally one or more thereof, and the water-soluble organic solvent is further optionally selected from the group consisting of isopropanol, ethanol, and methanol, and further optionally, the water-soluble organic solvent is isopropyl alcohol. 16. The method according to any one of embodiments 13 to 15, wherein the polymer is PEO, PVP, or a mixture thereof. 17. The method according to any one of embodiments 13 to 16, wherein the ratio of water to the water-soluble organic solvent is from about 2:1 to about 1:5. 18. The method according to any one of embodiments 13 to 17, wherein the dispersed gum particles are present in the dispersion at a solids concentration (wt / v) of from about 5% to about 50%. 19. The method according to any one of embodiments 13 to 18, wherein the concentration (wt / v) of the polymer dissolved in the dispersion is from about 20% to about 0.25%. 20. A method of using the article according to any one of embodiments 8 to 12, the method comprising contacting the article with an aqueous sample containing one or more microorganisms to form an inoculated article, incubating the inoculated article for a period sufficient for the microorganisms to undergo at least one round of growth, and detecting the presence of the microorganisms. 21. The method according to embodiment 20, further comprising counting the microorganisms. 22. A liquid component comprising water, a water-soluble organic solvent that is at least partially soluble in water, or both, gum particles dispersed in the liquid component, and a water-soluble polymer dissolved in the liquid component to form a dispersion. 23. The dispersion according to embodiment 22, wherein the gum particles comprise one or more of guar gum, xanthan gum, or locust bean gum. 24. The aqueous organic solvent is selected from the group consisting of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether, and acetone, optionally selected from the group consisting of isopropanol, ethanol, and methanol, and further optionally, the aqueous organic solvent is isopropyl alcohol, the dispersion according to embodiment 22 or 23. 25. The ratio of water to the aqueous organic solvent is from about 2:1 to about 1:5, the dispersion according to any one of embodiments 22 to 24. 26. The dispersed gum is present at a solids concentration (wt / v) of from about 5% to about 60%, or from about 30% to about 60%, or from about 50% to about 60%, the dispersion according to any one of embodiments 22 to 25. 27. The concentration (wt / v) of the dissolved polymer is from about 20% to about 0.5%, the dispersion according to any one of embodiments 22 to 26. 28. The organic polymer is PEO, PVP, or a mixture thereof, the dispersion according to any one of embodiments 22 to 27. 29. The dispersed gum is present at a solids concentration (wt / v) of from about 5% to about 60%, the dispersion according to any one of embodiments 22 to 28. 30. The concentration (wt / v) of the dissolved polymer is from 20% to 0.5%, the dispersion according to any one of embodiments 22 to 29. 31. The viscosity of the dispersion is from about 200 cP to about 10000 cP, the dispersion according to any one of embodiments 22 to 30 or the method according to any one of embodiments 12 to 18. 32. The film has a total coat weight in the range of about 500 mg / 154.84 cm 2 (500 mg / 24 in 2 ) to about 2500 mg / 154.84 cm 2 (2500 mg / 24 in 2 ), the film according to any one of embodiments 1 to 7 or the article according to any one of embodiments 8 to 12. 33. The dispersion has a total coat weight in the range of about 500 mg / 154.84 cm after drying 2 (500 mg / 24 in 2 ) to about 2500 mg / 154.84 cm2 (2500 mg / 24 in 2 ) to form a film having a total coat weight in the range of the method according to any one of Embodiments 13 to 19 or the dispersion according to any one of Embodiments 22 to 31.

[0096] Reference To more fully explain and disclose the present invention and the current state of the art related to the present invention, a number of patents and publications are cited above. The complete citations of these references are shown below. Each of these references is incorporated by reference into the present disclosure to the same extent as if each individual reference was specifically and individually indicated to be incorporated by reference.

[0097] All publications mentioned in this specification are incorporated by reference to the extent that they support the present invention.

Claims

1. A film comprising a plurality of particles of a water-soluble gum and a water-soluble polymer that contacts at least a portion of the surface of the particles of the water-soluble gum, having a total coat weight in the range of about 500 mg / 154.84 cm ２ (500 mg / 24 in ２ ) to about 2500 mg / 154.84 cm ２ (2500 mg / 24 in ２ ), or about 700 mg / 154.84 cm ２ (700 mg / 24 in ２ ) to about 2400 mg / 154.84 cm ２ (2400 mg / 24 in ２ ), or about 700 mg / 154.84 cm ２ (700 mg / 24 in ２ ) to about 2000 mg / 154.84 cm ２ (2000 mg / 24 in ２ ).

2. The film according to claim 1, wherein the water-soluble polymer is also soluble in a solution of water and a water-soluble organic solvent, the water-soluble organic solvent is optionally selected from the group consisting of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether, and acetone, the water-soluble organic solvent is further optionally selected from the group consisting of isopropanol, ethanol, and methanol, and further optionally, the water-soluble organic solvent is isopropyl alcohol.

3. The film according to claim 1 or 2, wherein the polymer is selected from PEO and PVP.

4. The film according to any one of claims 1 to 3, wherein the water-soluble gum is capable of gelling when contacted with cold water.

5. The film according to any one of claims 1 to 4, wherein the gum is selected from guar gum, locust bean gum, and xanthan gum, and optionally, the gum is guar gum.

6. The film according to any one of claims 1 to 5, wherein at least a part of the particles of the water-soluble gum is completely entrained by the water-soluble polymer.

7. The film according to any one of claims 1 to 6, wherein the ratio of the polymer to the gum is from about 1:200 or more to about 2:1 or less, optionally from about 1:100 or more to about 1:1 or less.

8. An article comprising a substrate and the film according to any one of claims 1 to 7 in contact with at least a part of a first major surface of the substrate, wherein the substrate comprises at least one of plastic, metal or glass, and preferably the substrate comprises plastic.

9. The article according to claim 8, wherein the portion of the first major surface of the substrate in contact with the film has no adhesive.

10. The article according to claim 8 or 9, wherein the film is disposed in a growth compartment of a thin film culture device.

11. The article according to any one of claims 8 to 10, wherein the film further comprises at least one nutrient for promoting the growth of at least one microorganism.

12. The article according to any one of claims 8 to 11, wherein the film further comprises at least one dye, optionally at least one redox dye.

13. A method of manufacturing an article, dispersing particles of at least one water-soluble gum in a liquid containing water, at least one water-soluble organic solvent, or a mixture of water and at least one organic solvent, and dissolving at least one water-soluble polymer in the liquid containing water, at least one water-soluble organic solvent, or a mixture of water and at least one organic solvent to form a dispersion of the particles of the at least one water-soluble gum and the at least one water-soluble polymer in the liquid to form a dispersion, Solvent coating the dispersion liquid onto a substrate to form a film on the substrate and comprising the article is optionally an article according to any one of claims 8 to 12, the film is optionally a film according to any one of claims 1 to 7, method.

14. The method according to claim 13, further comprising drying the article to a certain mass.

15. The at least one organic solvent comprises one or more of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether and acetone, or is optionally one or more of them, and the water-soluble organic solvent is further optionally selected from the group consisting of isopropanol, ethanol and methanol, and further optionally, the water-soluble organic solvent is isopropyl alcohol. The method according to claim 13 or 14.

16. The method according to any one of claims 13 to 15, wherein the polymer is PEO, PVP or a mixture thereof.

17. The method according to any one of claims 13 to 16, wherein the ratio of the water to the water-soluble organic solvent is about 2:1 to about 1:

5.

18. The method according to any one of claims 13 to 17, wherein the particles of the dispersed gum are present in the dispersion liquid at a solids concentration (wt / v) of about 5% to about 50%.

19. The method according to any one of claims 13 to 18, wherein the concentration (wt / v) of the polymer dissolved in the dispersion liquid is about 20% to about 0.25%.

20. A method of using the article according to any one of claims 8 to 12, comprising contacting the article with an aqueous sample containing one or more microorganisms to form an inoculated article, incubating the inoculated article for a period sufficient for the microorganisms to undergo at least one round of growth, and detecting the presence of the microorganisms.

21. The method according to claim 20, further comprising counting the microorganisms.

22. A liquid component comprising water, a water-soluble organic solvent that is at least partially soluble in the water, or both, gum particles dispersed in the liquid component, and a water-soluble polymer dissolved in the liquid component A dispersion comprising.

23. The dispersion according to claim 22, wherein the gum particles comprise one or more of guar gum, xanthan gum, or locust bean gum.

24. The water-soluble organic solvent is selected from the group consisting of isopropanol, ethanol, methanol, tetrahydrofuran, diethyl ether, methyl ethyl ether, dimethyl ether, and acetone, optionally selected from the group consisting of isopropanol, ethanol, and methanol, and further optionally, the water-soluble organic solvent is isopropyl alcohol. The dispersion according to claim 22 or 23.

25. The ratio of the water to the water-soluble organic solvent is from about 2:1 to about 1:

5. The dispersion according to any one of claims 22 to 24.

26. The dispersed gum is present at a solids concentration (wt / v) of 50 to 5%. The dispersion according to any one of claims 22 to 25.

27. The concentration (wt / v) of the dissolved polymer is from about 20 to about 0.5%. The dispersion according to any one of claims 22 to 26.

28. The dispersion according to any one of claims 22 to 27, wherein the organic polymer is PEO, PVP or a mixture thereof.

29. The dispersion according to any one of claims 22 to 28, wherein the dispersed gum is present at a solids concentration of 50 to 5% (wt / v).

30. The dispersion according to any one of claims 22 to 29, wherein the concentration (wt / v) of the dissolved polymer is 20 to 0.5%.

31. The dispersion according to any one of claims 22 to 30, or the method according to any one of claims 12 to 18, wherein the viscosity of the dispersion is from about 200 to about 10000 cP.

32. The film has a total coat weight in the range of about 500 mg / 154.84 cm ２ (500 mg / 24 in ２ ) to about 2500 mg / 154.84 cm ２ (2500 mg / 24 in ２ ), the film according to any one of claims 1 to 7, or the article according to any one of claims 8 to 12.

33. The dispersion forms a film having a total coat weight in the range of about 500 mg / 154.84 cm ２ (500 mg / 24 in ２ ) to about 2500 mg / 154.84 cm ２ (2500 mg / 24 in ２ ), the method according to any one of claims 13 to 19, or the dispersion according to any one of claims 22 to 31.

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