Articles and methods of use for sampling surfaces for microorganisms

Abstract

To provide a sampling article for effectively dislodging and picking up samples, which dislodges samples such as biofilms from surfaces without killing microbes, without disrupting cell membranes of the microbes, and without otherwise adversely impacting sample integrity.SOLUTION: An article 1 comprises an inner layer 11 contained in one or more outer layers 10. The inner layer 11 comprises a hydrophilic absorbent porous textile having a solid content of 0.5%-30%, optionally 0.5%-15%. The one or more outer layers 10 comprise a porous hydrophilic wicking textile having a solid content of about 2%-40%.SELECTED DRAWING: Figure 1

Description

[Background technology]

[0001] WO 2015123635, USD 809234, and US 20170051442 describe scraping articles. Such articles are not always useful or convenient for collecting microbial samples. [Brief description of the drawings]

[0002] [Figure 1] FIG. 2 is a cutaway side view of a portion of the sampling article. [Diagram 2] FIG. 2 is a cutaway side view of a portion of the sampling article. [Diagram 3] FIG. 2 is a top view of the sampling article. [Figure 4] FIG. 2 is a side view of the sampling article. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0003] Throughout this disclosure, the singular forms "a," "an," and "the" are often used for convenience, but should be understood to be intended to include the plural unless the singular form is expressly designated singularly, for example, by the terms "one and only one," or unless otherwise clearly indicated by context.

[0004] A layer disposed over a "portion" of the second layer is disposed over a portion of the second layer, but less than all of the second layer. Typically, a layer disposed over a portion of the second layer is disposed over at least 1%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or even 90% of the second layer, but most commonly over 70%, 60%, 50%, 40%, 30%, 20%, or even 10% or less of the second layer. Most often, a layer disposed over a portion of the second layer is disposed over 20%-60% of the second layer.

[0005] A layer disposed over "at least a portion" of a second layer can be disposed over a portion of the second layer, or over the entire second layer.

[0006] Unless specifically used with reference to the prior art, terms such as "common," "typical," and "often" are used to refer to features or embodiments commonly used in this disclosure. The use of such terms is not intended to imply that the feature or embodiment being discussed has been previously known or is significantly less than is commonly known.

[0007] The "solid content" of a nonwoven fabric refers to the percentage of solids in the nonwoven fabric by mass per volume. Solid content can be calculated as the basis weight of the nonwoven fabric divided by the product of the thickness of the nonwoven fabric normalized to 100% and the density of the solids, usually polymers, used to make the nonwoven fabric. This can be expressed as m / (p*L), where m is the basis weight in units of mass per area (such as grams per square meter), p is the thickness in units of distance (such as meters), and L is the density of the solids, usually polymers, in the nonwoven fabric in units of mass per volume (such as grams per cubic meter). The result is a dimensionless value that can be expressed as a percentage. Solid content is sometimes referred to as "solidity" in the art, but when the terms solid content and solidity are used in the art, they may not be used in the same sense as the term "solid content" is used herein.

[0008] A problem with sampling devices relates to removing the sample from the device. Once a sample, such as an aqueous sample, is obtained, it can be difficult to release the sample from a sampling device that typically contains a sponge or sponge-like material. It would be preferable to remove the sample without requiring excessive squeezing or manipulation of the sample device.

[0009] Sampling surfaces, such as environmental surfaces, drains, work surfaces, machine surfaces, food preparation surfaces, or even surfaces of living organisms (living or dead), to detect microorganisms on such surfaces can be important, for example, to determine whether the surface is contaminated with a microorganism. Such contamination can result in food spoilage, illness, and other problematic consequences. Current sampling articles and methods can produce inaccurate results or false negatives, especially when food buildup or biofilm is present on the surface being sampled. Such inaccuracies or false negatives can manifest themselves, for example, in the case where a sample obtained by a current sampling device is analyzed for the presence of a microorganism by culturing the sample for a particular microorganism, resulting in no detection of the microorganism, even though the microorganism being cultured is present on the sampled surface.

[0010] The present disclosure recognizes two mechanisms that give rise to such inaccuracies or false negatives associated with sampling devices. First, the sampling device may be unable to collect microorganisms from the sampled surface. This is particularly problematic in the presence of microorganisms or samples that are difficult to remove from the sampled surface, such as biofilms. Biofilms and other samples that are difficult to remove may resist transfer from the sampling surface to the sampling device. Thus, it may be possible to inaccurately conclude that no microorganisms are present on the sampled surface when in fact microorganisms are present but have not been transferred to the sampling device. This erroneous conclusion is a type of false negative.

[0011] Second, even if microorganisms are transferred from the sampled surface to the sampling device, the sampling device itself may kill some or all of the microorganisms, thereby skewing the results or giving a false negative. For example, if an abrasive is used to disrupt the biofilm prior to sampling, the abrasive may disrupt the microbial cell membrane and kill the microorganisms. Also, if a biocide is present in the sampling device, the biocide may affect the recovery of microorganisms, especially low levels of microbial bioburden, due to its inherent residual killing power. In particular, sponges, which are often used to collect samples in sampling devices, are typically made in the presence of water (known as a "wet environment") and thus require the addition of a biocide to prevent microorganisms from growing on the sponge. Thus, the inventors have recognized that sponges and other sampling devices having residual biocides or harsh abrasives on the sampling device may adversely affect the integrity of the sample, even if microorganisms are transferred from the surface to the sampling device. This is particularly problematic when it is desired to culture the microorganisms, since microorganisms killed during the collection process will not grow to form colony units.

[0012] Another problem to be solved is how to avoid or at least reduce the occurrence of false negatives caused by sampling devices. Another problem is how to effectively remove and collect samples, particularly difficult to remove samples such as biofilms from surfaces, without killing the microorganisms, disrupting the cellular membranes of the microorganisms, or otherwise adversely affecting the integrity of the sample.

[0013] Briefly, a solution to one or more of these problems resides in an article that includes an inner layer contained within one or more outer layers, the inner layer comprising: A hydrophilic absorbent textile comprising: They can be woven, nonwoven, or knitted, but are most often It is a nonwoven fabric, 0.5% to 30%, more specifically 0.5% to 15% solids. death , one or more outer layers are A porous hydrophilic wicking nonwoven fabric is included,They can be woven, nonwoven, or knitted, but are most often It is a nonwoven fabric, Solids content: 2% to 40% do. The scrubbing layer can be disposed over at least a portion of one of the one or more outer layers.

[0014] In particular, at least one of the one or more outer layers is a nonwoven fabric. In particular cases, the inner layer is a nonwoven fabric. In particular cases, the one or more outer layers are a nonwoven fabric and the inner layer is a woven fabric. In particular cases, the one or more outer layers are a nonwoven fabric and the inner layer is a knitted fabric. In particular cases, the one or more outer layers are a woven fabric and the inner layer is a nonwoven fabric. In particular cases, the one or more outer layers are a woven fabric and the inner layer is a woven fabric. In particular cases, the one or more outer layers are a nonwoven fabric and the inner layer is a nonwoven fabric. In the most particular case, which is the most common, all of the outer layers are nonwoven fabrics and the inner layer is a nonwoven fabric.

[0015] Regardless of the nature of the textile, the inner layer is made of a hydrophilic wicking material, which can be any hydrophilic wicking textile, usually a nonwoven, capable of absorbing an aqueous sample, especially an aqueous sample having one or more microorganisms. Any suitable hydrophilic fiber material can be used, such as rayon, wood pulp fibers, acrylic fibers nylon fibers, wool, cotton, nylon, polybutylene terephthalate (sometimes referred to in the art as PBT), hydrophilized polyolefins, such as hydrophilized polypropylene, hydrophilized polyethylene, or hydrophilized olefin copolymers, gauze, and the like. Fibers that are inherently hydrophobic can be used, in which case they can be finished with a hydrophilic coating. Most commonly, hydrophilic wicking materials include viscose fibers, rayon fibers, viscose / PET (polyethylene terephthalate) fibers, rayon / PET fibers, or any combination of the foregoing. When the fibers are viscose / PET or rayon / PET, the PET content is typically less than 70%, more commonly less than 60%, 50%, 40%, 30%, 20%, or even less than 10%. When PET is used, the typical PET content is about 40%-60%, although other contents can be used depending on the application and exact properties desired. When PET is used, it is often a coating on at least a portion of the fiber. In certain cases, the PET is thermally bonded to the fiber.

[0016] The solids content of the inner layer is about 0.5% to 15%. Particular solids contents are 0.5% or more, 2% or more, 5% or more, 7% or more, more than 10%, or even 12% or more. Particular solids contents are 15% or less, 12% or less, 10% or less, 7% or less, 5% or less, 2% or less, or even 1% or less. Materials with suitable solids contents can be produced by any suitable method, including carding, spunbonding, spunlacing, meltblowing, airlaying, creping, and the like. Some suitable processes are described in U.S. Pat. No. 7,393,371. Materials that can be used for the inner layer are also commercially available and include gauze, high loft nonwovens available under the trade name Reicofil from Reifenhauser Reicofil GmnH & Co. KG (Troisdorf, Germany), high loft nonwovens available under the trade name SURELIFT from Vita Nonwovens (High Point, NC, USA), and the like.

[0017] The solids content of the material in the inner layer is important to provide the correct properties: if the solids content is too high, it will be difficult to release all of the sample absorbed into the inner layer; if the solids content is too low, the inner layer will have insufficient structural integrity to remain together when wetted.

[0018] In particular, the inner layer can be made of cellulose-containing fibers, but the inner layer is not a sponge, especially not a cellulose sponge.Indeed, it is recognized that nonwoven fabrics, such as those used in the inner and outer layers of the article described herein, are structurally different from sponges and have physical properties different from those of sponges.The use of sponges as inner layers is not suitable for the present invention, since sponges do not have suitable release properties to release absorbed samples easily, preferably reproducibly.

[0019] The one or more outer layers include a porous hydrophilic wicking material, usually in the form of a textile, but particularly possibly a membrane. If a textile, it may be nonwoven, woven, or knit. The one or more outer layers have a solids content of about 2% to 40%. Particular values ​​may be 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, 25% or more, 30% or more, or even 35% or more. Particular values ​​may be 40% or less, 35% or less, 30% or less, 25% or less, 20% or less, 15% or less, or even 10% or less.

[0020] The solids content of the outer layer(s) is also important. If the solids content is too low, the outer layer(s) will Either the layers will not form together sufficiently to contain the inner layer when wet, or one or more of the outer layers will absorb too much water and the release characteristics of the overall device will not be sufficient. If the solids content is too high, the outer layer or layers will not be able to collect microorganisms from the surface being sampled.

[0021] The pore size of the one or more outer layers may be sufficient to allow microorganisms to pass through the pores, for example, 20 nm to 5 microns. While any suitable hydrophilic fiber material may be used, such as rayon, wood pulp fibers, acrylic fibers, nylon fibers, wool, cotton, fibers with a finishing hydrophilic coating, etc., most commonly hydrophilic wicking nonwovens use viscose fibers, rayon fibers, viscose / PET (polyethylene terephthalate) fibers, rayon / PET fibers, or combinations of any of the foregoing. When the fibers are viscose / PET or rayon / PET, the PET content is typically less than 70%, more commonly less than 60%, 50%, 40%, 30%, 20%, or even less than 10%. When PET is used, a typical PET content is about 15% to 35%, although other contents can be used depending on the application and exact properties desired. When PET is used, it may be, for example, thermally bonded to the fiber or to a coating on at least a portion of the fiber.

[0022] Materials having suitable solids and pore sizes for use in one or more outer layers can be produced by any suitable method, such as those described in U.S. Patent No. 7,393,371. Materials usable for the outer layers are also commercially available, including those available under the trade names SX567, grade 200 50 / 50 rayon / polyester spunlace, and SX632, all of which are available from Alstrom Corp., Green Bay, WI, USA, as well as those available under the trade name SONTARA, particularly SONTARA 8010, available from DuPont Nonwovens Inc., Old Hickory, TN, USA.

[0023] The inner layer and one or more outer layers are most often free of biocides. In some cases, possible but rarely employed, residual biocide may be present, but such residual biocide is insufficient to kill microorganisms on the sampling device or insufficient to kill the type of microorganism being detected, either because of the type of biocide or the concentration of the biocide. However, if a handle is used, it is possible for biocide to be present in or on the handle of the article, or in or other parts of the article that do not contact the surface or microorganisms being sampled.

[0024] The article may be made by any suitable process. The various layers of the article may be attached by any suitable bonding process, such as thermal bonding, adhesive bonding, hydroentangling, needle punching, calendaring, point bonding, and the like. If handles are used, they may be secured using these same techniques.

[0025] Various configurations of the inner layer and one or more outer layers are possible, two of which are discussed in detail here: The first configuration is shown in Figure 1, where the article 1 contains an outer layer 10 that is sealed with a seal 12. The inner layer 11 is completely contained within the outer layer 10.

[0026] A second primary configuration is shown in Figure 2. In this configuration, article 2 has a first outer layer 20 and a second outer layer 22 sealed together by seals 22a and 22b such that inner layer 23 is entirely contained within the first and second outer layers 20, 21.

[0027] In any configuration, the seal can be formed in any suitable manner, depending on the intended use of the article and the exact content of the inner and outer layers. Exemplary seals can be formed by using an adhesive or by heat sealing.

[0028] Other configurations are also possible. For example, three, four, or even more outer layers can be sealed together to include an inner layer as described above, in which case the cross-section of the inner and outer layers of the article may be approximately triangular, square, or some other shape. Such configurations are encompassed by the present disclosure, as numerous additional configurations are readily envisioned based on the present disclosure, and therefore not all possible configurations are described in detail.

[0029] It is often convenient to include a handle, such as handle 31 visible in Figure 3. If a handle is included, one or more outer layers, such as outer layer 32 in Figure 3, will typically be sealed to the handle in addition to being sealed to themselves.

[0030] Regardless of the configuration of the inner and outer layers, the scrubbing layer present in a portion of one or more of the outer layers is typically a cured resin. Optionally, the resin can have a plurality of abrasive particles embedded or otherwise contained within the resin. If used, the abrasive particles are typically mildly abrasive. If used, the abrasive particles typically have a Mohs hardness of at least 3. Glass beads may also be used.

[0031] Abrasive particles are not necessary in all cases, and in fact in some situations, such as when there is concern that the end user may scratch the surface being sampled, it may be advantageous to use a scrubbing layer that does not contain abrasive particles.

[0032] In principle, any resin can be used, regardless of whether abrasive particles are used. Particular resins that can be used include, for example, those that have very mild abrasive properties, so that scratches or damage to the surface to be sampled can be avoided. Cured phenolic resins are common because they are convenient to manufacture and place on one or more outer layers, but other resins can also be used. Abrasives and abrasive particles that can be used include those described in U.S. Pat. No. 7,393,371 and WO 2015123635. Scraping layers that can be used, even if they do not contain abrasive particles, include those disclosed in WO 2015123635.

[0033] The scrubbing layer can be arranged in different ways over a portion of one or more outer layers. The scrubbing layer can be continuous or discontinuous. If discontinuous, the scrubbing layer is generally arranged as a repeating pattern of one or more geometric shapes, such as circles, squares, lines, "sawtooth" or "snake" lines, triangles, diamonds, etc. An example of this configuration is shown in FIG. 3, which features an article 3 having an outer layer 30 and a handle 31. The outer layer 30 is sealed to itself and to the handle 31 with a seal 32. An inner layer, not visible in this view, is arranged within the outer layer 30, similar to the inner layer 11 depicted in FIG. 1. A discontinuous scrubbing layer is present as a plurality of circles 33 arranged in a repeating pattern on the outer layer 30. A discontinuous scrubbing layer is possible over the entire outer layer of an article, such as article 3, or over only a portion of the outer layer of the article.

[0034] A scrubbing layer can also be continuous. An example of a continuous scrubbing layer is scrubbing layer 43 of article 4 depicted in Figure 4. In Figure 4, there are two portions of outer layer 40. The first portion is not visible in the figure because it is completely covered by continuous scrubbing layer 43. The second portion of outer layer 40, on the opposite side of handle 41 from the first portion, is not covered by scrubbing layer 43. The two portions are sealed to each other and to handle 41 by seal 42.

[0035] In use, a method of collecting microorganisms from a surface can include contacting the microorganisms on the surface with at least a portion of the scrubbing layer of an article described herein, and subsequently contacting the microorganisms with at least a portion of the outer layer of an article described herein. In most cases, contacting with the scrubbing layer will include scrubbing the surface with the scrubbing layer.

[0036] Typically, the article, particularly one or more of its layers, or either of the surfaces, will be moistened during the process. Moistening is typically performed with water or an aqueous liquid. Buffered water is an exemplary aqueous liquid.

[0037] The method can be performed on almost any surface. Common surfaces to which the method may be applied include food preparation surfaces, work surface, or machine surfaces such as cutting, grinding, or sorting machines used in food preparation. Other surfaces that may be sampled include walls, drains, etc.

[0038] The method may also be applied to biological surfaces such as biofilm-coated surfaces, skin surfaces, or wound surfaces. When biological surfaces are used, the method may be useful, for example, to collect microorganisms that may be present on the surface of a food substance, or to collect microorganisms that may be present on the surface of a living organism for the ultimate purpose of identifying or enumerating the microorganisms present on the surface of the living organism.

[0039] The method may also include a step of releasing the microorganisms collected from the article, typically into a liquid. This may be accomplished, for example, by contacting the article with the liquid. The liquid may be any suitable liquid, such as, for example, a lysis buffer, a growth medium, a selective growth medium, an enrichment medium, etc. The microorganisms may also be released into a gel, such as a gelling medium.

[0040] The method may further include additional steps such as culturing the microorganism, identifying the microorganism, enumerating the microorganism, or a combination of one or more of the foregoing steps. EXAMPLES

[0041] These examples illustrate certain specific embodiments or implementations of the present disclosure and are not intended to limit the scope of the appended claims, which may include both these examples and other embodiments or implementations, because other embodiments and implementations are also contemplated.

[0042] material BB-077 phenolic resin (70% aqueous solution), commercially available from Arclin, Mississauga, Ontario.

[0043] SNOWHITE 12-PT filler, calcium carbonate powder (density of 2.7 cm3), commercially available from Omya International AG, Oftringen, Switzerland.

[0044] MAXI-CLEAN 100 mesh, hardened, melamine resin granules (4.0 Mohs hardness) available from Maxi-Blast Inc., South Bend, IN.

[0045] MAXI-CLEAN 200 mesh, hardened, melamine resin granules (4.0 Mohs hardness), commercially available from Maxi-Blast Inc., South Bend, IN.

[0046] XIAMETER AFE-1010 defoamer emulsion, commercially available from Dow Chemical, Midland, MI.

[0047] SUNSPERSE Blue (BCD 9680) blue pigment, commercially available from Sun Chemical Corporation, Cincinnati, Ohio.

[0048] ARCOL LG-650 polyether polyol crosslinker, commercially available from Covestro, Pittsburgh, PA.

[0049] CAB-O-SIL M-5 filler, an untreated, amorphous, synthetic fumed silica with a specific surface area of ​​200 m2 / g, commercially available from Cabot Corporation, Billerica, MA.

[0050] ROVENE 5900 latex, a carboxylated styrene-butadiene emulsion having a Brookfield viscosity of 200 cps (#2 spindle / 20 rpm) and a pH of 9.0, commercially available from Mallard Creek Polymers, Incorporated, Charlotte, NC.

[0051] XIAMETER AFE-1520 silicone emulsion (density of 1.0 g / mL and pH 4), commercially available from Dow Corning Corporation, Midland, MI.

[0052] SUNSPERSE (RPD 2542) liquid red pigment, commercially available from Sun Chemical Corporation, Cincinnati, Ohio.

[0053] INDOLUBE PPL surfactant, a non-ionic stabilizer for latex emulsions (density of 1.02 g / mL), commercially available from Indusco, Ltd., Greensboro, NC.

[0054] LYCOPRINT PT-XN thickener, a fully neutralized anionic acrylic polymer dispersion (density of 1.1 g / mL), commercially available from Huntsman International LLC, High Point, NC.

[0055] [Table 1]

[0056] The ingredients of Resin Formulation A (Table 1) were combined in 1000 g batches in a hard plastic container and a plastic lid was attached to the container. The mixture was mixed in a centrifugal mixer (model "SPEEDMIXER DAC400.1VAC-P" obtained from Flaktek, Inc., Landrum, SC) for approximately 60 minutes.

[0057] [Table 2]

[0058] The ingredients of Resin Formulation B (Table 2) were combined in 1000 g batches in a hard plastic container and a plastic lid was attached to the container. The mixture was mixed in a centrifugal mixer (model "SPEEDMIXER DAC400.1VAC-P" obtained from Flaktek, Inc., Landrum, SC) for approximately 60 minutes.

[0059] Example 1. A three-ply sampling article was prepared having an inner layer and two outer layers. The first outer layer of the nonwoven web (SONTARA brand (material number 3006871) obtained from Jacob Holm Group, Basel, Switzerland) was a blend of PET fibers (60% by weight) and viscose fibers (40% by weight). The density of the PET fibers was about 1.38 g / cm3 and the density of the viscose fibers was about 1.49 g / cm3. The nominal basis weight of the web was 43 grams per square meter (gsm) and the thickness of the web was about 0.8 mm. The solids content of the nonwoven web was about 3.8%.

[0060] The second outer layer of the nonwoven web [SONTARA brand obtained from Jacob Holm Group (material number 3006871)] was a blend of PET fibers (60% by weight) and viscose fibers (40% by weight). The density of the PET fibers was about 1.38 g / cm3 and the density of the viscose fibers was about 1.49 g / cm3. The nominal basis weight of the web was 43 grams per square meter (gsm) and the thickness of the web was about 0.8 mm. The solids content of the nonwoven web was about 3.8%. A rub-off layer was applied in a dot pattern to one surface of the second outer layer using a rotary screen printing apparatus and a slurry of Resin Formulation A (described above). A stencil was used to create a repeating dot pattern. The stencil had 2.5 mm diameter holes with 7.5 mm center-to-center spacing in offset rows. The resulting printed web was passed through a heating apparatus (set at 1.7 meters per minute and 160° C.) to solidify the dots of resin.

[0061] The inner layer of the nonwoven web was prepared using a conventional air-laying web former (available under the tradename RANDO WEBBER from Rando Machine Company, Macedon, New York). The web was a blend of viscose fibers (52 wt%), PET fibers (18 wt%), and melt fibers (30 wt%). The viscose fibers (10-18 micron diameter) were obtained as LENZING viscose fibers from Lenzing Group (Lenzing, Austria) and had a fiber length of 3.9 cm. The PET fibers (3 denier) were obtained from INVISTA Company (Wichita, KS) and had a fiber length of 3.8 cm. The melt fibers (4 denier) were Tairin polyester type LML41 (NanYa Plastics Corporation, Kaohsiung City, Taiwan) and had a fiber length of 5 cm. The resulting nonwoven web had a nominal basis weight of 222 grams per square meter (gsm) and a web thickness of 5.2 mm. The solids content of the nonwoven web was about 2.9%. The web was needle tacked and thermally bonded by passing the web through a heating apparatus (set at 1.1 meters per minute and 138° C.).

[0062] Each nonwoven layer was cut into a 1.5 inch by 3 inch (3.8 cm by 7.6 cm) piece. The layers were stacked and the edges aligned so that one surface of the inner nonwoven layer was in contact with the first outer layer and the opposite surface of the inner layer was in contact with the second outer layer. The second outer layer was oriented so that the scraping layer was exposed (i.e., facing away from the inner layer). The edges were heat sealed at 232°C to form the finished sampling article.

[0063] Example 2. A three-ply sampling article was prepared having an inner layer and two outer layers. The first outer layer of the nonwoven web (SONTARA brand (material number 444515177) obtained from Jacob Holm Group, Basel, Switzerland) was a blend of PET fibers (45% by weight) and wood pulp (55% by weight). The density of the PET fibers was about 1.38 g / cm3. The nominal basis weight of the web was 65 grams per square meter (gsm) and the thickness of the web was about 0.26 mm. The solids content of the nonwoven web was about 17.9%.

[0064] The second outer layer of the nonwoven web [SONTARA brand obtained from Jacob Holm Group (material number 444515177)] was a blend of PET fibers (45% by weight) and wood pulp (55% by weight). The density of the PET fibers was about 1.38 g / cm3. The nominal basis weight of the web was 65 grams per square meter (gsm), and the thickness of the web was about 0.26 mm. The solids content of the nonwoven web was about 17.9%. A rub-off layer was applied in a dot pattern to one surface of the second outer layer using a rotary screen printing apparatus and a slurry of Resin Formulation B (described above). A stencil was used to create a repeating dot pattern. The stencil had 2.5 mm diameter holes with 7.5 mm center-to-center spacing in offset rows. The resulting printed web was passed through a heating apparatus (set at 1.7 meters per minute and 160° C.) to solidify the dots of resin.

[0065] The inner layer of the nonwoven web was prepared using a conventional air-laying web former (available under the tradename RANDO WEBBER from Rando Machine Company, Macedon, New York). The web was a blend of viscose fibers (52 wt%), PET fibers (18 wt%), and melt fibers (30 wt%). The viscose fibers (10-18 micron diameter) were obtained as LENZING viscose fibers from Lenzing Group (Lenzing, Austria) and had a fiber length of 3.9 cm. The PET fibers (3 denier) were obtained from INVISTA Company (Wichita, KS) and had a fiber length of 3.8 cm. The melt fibers (4 denier) were Tairin polyester type LML41 (NanYa Plastics Corporation, Kaohsiung City, Taiwan) and had a fiber length of 5 cm. The resulting nonwoven web had a nominal basis weight of 222 grams per square meter (gsm) and a web thickness of 5.2 mm. The solids content of the nonwoven web was about 2.9%. The web was needle tacked and thermally bonded by passing the web through a heating apparatus (set at 1.1 meters per minute and 138° C.).

[0066] Each nonwoven layer was cut into a 1.5 inch by 3 inch (3.8 cm by 7.6 cm) piece. The layers were stacked and the edges aligned so that one surface of the inner nonwoven layer was in contact with the first outer layer and the opposite surface of the inner layer was in contact with the second outer layer. The second outer layer was oriented so that the scraping layer was exposed (i.e., facing away from the inner layer). The edges were heat sealed at 232°C to form the finished sampling article.

[0067] Example 3. Testing of Articles to Retrieve Bacterial Samples (cfu) from Surfaces A 10 mL bacterial suspension containing a mixture of Escherichia coli (ATCC 35150) and Salmonella typhimurium (ATCC 51812) was prepared using an overnight culture of each strain grown for 24 h at 35° C. in 5 mL of tryptic soy broth (Thermo Fisher Scientific, Waltham, MA). The suspension was serially diluted in Butterfield's buffer (3M Corporation, St. Paul, MN) to a target concentration of approximately 500 cfu / mL (colony forming units / mL).

[0068] Stainless steel coupons (10.2 cm x 10.2 cm) were individually placed in glass Petri dishes and sterilized in an autoclave at 121°C for 15 minutes. The entire surface of one side of each coupon was coated with 1 mL of bacterial suspension using a FISHERBRAND L-shaped cell spreader (Thermo Fisher Scientific). The coated stainless steel coupons were allowed to air dry under ambient conditions until no visible inoculum was found. The dried coupons were tested for bacterial removal using either the finished article of Example 1, a dry, biocide-free, gamma-irradiated, cellulose sponge (3.8 cm x 7.6 cm) obtained from 3M Corporation (Product No. BP133ES) (Comparative Article A), or a polyurethane foam sponge (3.8 cm x 7.6 cm) cut from a polyurethane foam sheet obtained from Woodbridge INAOC Technical Products, Chattanooga, TN (Comparative Article B). The polyurethane sponge was sterilized using ethylene oxide (37°C, 60% relative humidity, 3 hour exposure). Tests were performed in triplicate using a single sampling article for each coupon (test coupon numbers 1-3). Each sampling article was moistened with 10 mL of sterile Butterfield's buffer (3M Corporation). The coated surface of each coupon was sampled using the moistened article according to the procedure described in Section 7.5.4.2 of the ISO18593:2018 standard, "Microbiology of the Food Chain-Horizontal Methods for Surface Sampling" (International Organization for Standardization, Geneva, Switzerland).

[0069] For the coupons tested with the articles of Example 1, each coupon was first gently rubbed against the surface of the article containing the scrubbing layer, and then the opposite non-scrubbing surface of the article (i.e., the nonwoven first layer) was used to wipe off the collection of bacterial analytes. After sampling of the coupons, each article was sealed in a separate polyethylene / polyester laminate (gamma irradiated) sample bag (12.7 cm x 22.9 cm, product number SSL100, from 3M Corporation) and stored in a refrigerator (2-8°C) for 96 hours before being counted.

[0070] The counts were performed by the following procedure: The outside of each bag was manually squeezed for 2 minutes to release the liquid from the article into the bag. Two 1 mL liquid samples (Sample 1 and Sample 2) were removed from each bag using a pipette and individually inoculated onto separate 3M PETRIFILM Rapid Aerobic Count (PRAC) plates (3M Corporation) according to the manufacturer's instructions. The inoculated plates were incubated at 35° C. for 24 hours. After the incubation period, the total colony counts (cfu) on each plate were determined using a 3M PETRIFILM plate reader (3M Corporation). The results are reported in Table 3.

[0071] [Table 3]

[0072] Example 4. Testing of Articles for Release of Bacterial Samples (cfu) from the Articles Bacterial suspensions of E. coli (ATCC35150) and Salmonella typhimurium (ATCC51812) were prepared as described in Example 3. Sterile NASCO WHIRL-PAK sample bags (product number 01-812-1A, Thermo Fisher Scientific) were individually assembled with each bag containing a single sampling article selected from either the article of Example 1, Comparative Article 1, or Comparative Article 2. Each sampling article was moistened with 10 mL of sterile Butterfield's buffer (3M Corporation) and then inoculated with 1 mL of bacterial suspension (target concentration of 500 cfu / mL). After inoculation, each bag was sealed with the corresponding sampling article inside and stored in a refrigerator (2-8°C) for 96 hours. Bags containing each type of sampling article were prepared in triplicate.

[0073] Each bag was then removed from the refrigerator and the outside of each bag was squeezed by hand for 2 minutes to release the liquid from the article into the bag. Two 1 mL liquid samples (Sample 1 and Sample 2) were removed from the bag using a pipette and individually inoculated onto separate 3M PETRIFILM Rapid Aerobic Count (PRAC) plates (3M Corporation) according to the manufacturer's instructions. The inoculated plates were incubated at 35° C. for 24 hours. After the incubation period, the total colony count (cfu) on each plate was determined using a 3M PETRIFILM plate reader (3M Corporation). The results are reported in Table 4.

[0074] [Table 4]

[0075] Example 5. Testing of Articles for Release of Bacterial Samples (cfu) Using E. coli as Inoculum A 10 mL bacterial suspension containing a mixture of E. coli (ATCC35150) was prepared using an overnight culture grown in 5 mL of tryptic soy broth (Thermo Fisher Scientific) for 24 h at 35°C. The suspension was serially diluted in Butterfield's buffer (3M Corporation) to target concentrations of approximately 30-100 cfu / mL.

[0076] Sterile WHIRL-PAK sample bags (product number 01-812-1A, Thermo Fisher Scientific) were individually assembled containing a single sampling article selected from either the Example 1 article, the Example 2 article, or the negative control article. The articles of Example 1 and Example 2 were moistened with 10 mL of sterile Butterfield's buffer (3M Corporation) and then inoculated with 1 mL of E. coli suspension. Negative control articles were prepared by omitting the addition of E. coli suspension to the moistened articles of Examples 1 and 2. Each bag was then sealed with the corresponding sampling article inside. The bags were separated into two sets of 9 bags (3 bags of each type of sample article in the set).

[0077] After inoculation, the articles in the first set of bags were tested immediately (test time = 0 hours). Each bag in the first set was squeezed by hand for 2 minutes to release the liquid from the article into the bag. Two 1 mL liquid samples (sample 1 and sample 2) were removed from each bag using a pipette and individually inoculated onto separate 3M PETRIFILM Rapid Aerobic Count (PRAC) plates (3M Corporation) according to the manufacturer's instructions. The inoculated plates were incubated at 35°C for 24 hours. After the incubation period, the total colony count (cfu) of each plate was determined using a 3M PETRIFILM plate reader (3M Corporation).

[0078] After the inoculation step, the second set of bags were stored in a refrigerator (2-8°C) for 96 hours. The bags were removed from the refrigerator and tested using the same procedure described for the first set (test time = 96 hours). The results are reported in Tables 5 and 6. No colony growth (cfu counts) was observed for the negative control articles.

[0079] [Table 5]

[0080] [Table 6]

[0081] Example 6. Testing of articles for release of bacterial samples (cfu) using Salmonella typhimurium as inoculum The same procedure was followed as described in Example 5, except that a suspension of Salmonella typhimurium (ATCC 51812) was used as the inoculum (1 mL with a target concentration of approximately 30-100 cfu / mL) instead of the E. coli suspension. The results are reported in Tables 7 and 8. No colony growth (cfu counts) was observed for the negative control articles.

[0082] [Table 7]

[0083] [Table 8]

[0084] Example 7. Listeria monocytogenes as inoculum Testing of articles for release of bacterial specimens (cfu) for use in The same procedure was followed as described in Example 5, except that a suspension of Listeria monocytogenes (ATCC 7644) was used as the inoculum (1 mL with a target concentration of approximately 30-100 cfu / mL) instead of the E. coli suspension. The results are reported in Tables 9 and 10. No colony growth (cfu counts) was observed for the negative control articles.

[0085] [Table 9]

[0086] [Table 10]

Claims

1. An article for collecting a sample of microorganisms from a surface, comprising: The article has an inner layer, one or more outer layers, and a scrub layer; the inner layer is contained within the one or more outer layers; the inner layer comprises a hydrophilic absorbent porous textile; the one or more outer layers comprise a porous hydrophilic wicking textile; the scrubbing layer is disposed over a portion of at least one of the one or more outer layers; the article includes one or more second portions of the one or more outer layers; the scrubbing layer is not disposed over the one or more second portions of the one or more outer layers; the inner layer having a solids content of 0.5% to 30%; The article, wherein the one or more outer layers have a solids content of from 2% to 40%.

2. The article of claim 1, wherein said hydrophilic, absorbent, porous textile has a solids content of 0.5% to 15%.

3. 3. The article of claim 1 or 2, wherein the scraping layer is adapted to physically disrupt the biofilm without lysing cells contained within the biofilm.

4. The article of any one of claims 1 to 3, wherein the scrubbing layer comprises a cured resin.

5. The article of any one of claims 1 to 4, wherein the scrubbing layer comprises a plurality of abrasive particles having a Mohs hardness of 3 or greater.

6. The article of any one of claims 1 to 5, wherein the scrubbing layer comprises a plurality of abrasive particles, the plurality of abrasive particles comprising glass particles, ceramic particles, or a combination thereof.

7. The article of any one of claims 1 to 6, wherein the hydrophilic, absorbent, porous textile of the inner layer comprises viscose fibers, rayon fibers, or both viscose and rayon fibers.

8. The article of any one of claims 1 to 7, wherein the porous hydrophilic wicking textile of the one or more outer layers comprises viscose fibers, rayon fibers, or both viscose and rayon fibers.

9. 9. The article of claim 7 or 8, wherein at least a portion of the viscose or rayon fibers are thermally bonded to poly(ethylene terephthalate).

10. a first outer layer and a second outer layer; the first outer layer is sealed to the second outer layer with one or more seals; The article of any one of claims 1 to 9, wherein the inner layer is disposed between the first outer layer and the second outer layer.

11. It includes a single outer layer, the single outer layer being sealed to itself with one or more seals; The article of any one of claims 1 to 9, wherein the inner layer is contained within the single outer layer.

12. 12. The article of any one of claims 1-11, wherein the scrubbing layer is disposed on at least a first portion of the one or more outer layers in the form of a plurality of lines or geometric shapes across two or more first portions of the one or more outer layers, the plurality of lines or geometric shapes being present in a repeating pattern on the one or more outer layers.

13. The article according to any one of claims 4 to 12, wherein the resin is a phenolic resin.

14. The article of any one of claims 1 to 13, further comprising a handle.

15. The outer layer of any one of claims 12 to 14, wherein the first portion of the one or more outer layers is on an opposite side of the article from the second portion of the one or more outer layers.

16. The article of any one of claims 1 to 15, wherein the inner layer comprises a hydrophilic, absorbent, porous textile selected from nonwovens, wovens, and knits.

17. The article of any one of claims 1 to 16, wherein the hydrophilic, absorbent, porous textile is a nonwoven fabric.

18. The article of any one of claims 1 to 17, wherein the one or more outer layers comprise a porous, hydrophilic, wicking textile selected from nonwovens, wovens, and knits.

19. The article of any one of claims 1 to 18, wherein the porous hydrophilic wicking textile is a nonwoven fabric.

20. The article of any one of claims 1 to 19, wherein the inner layer and the one or more outer layers are biocide-free.

21. A method for collecting a sample of microorganisms from a surface, comprising contacting the surface with an article according to any one of claims 1 to 20.

22. 22. The method of claim 21, wherein the surface is a food preparation surface, a work surface, or a machine surface.

23. 22. The method of claim 21, wherein the surface is a biological surface.

24. 24. The method of claim 23, wherein the biological surface is a biofilm-coated surface, a skin surface, or a wound surface.

25. 25. The method of any one of claims 21 to 24, wherein the article is the article of claim 14, and the method comprises rubbing the surface with the scrubbing layer and subsequently contacting the surface with the second portion of the outer layer.

26. The method of any one of claims 21 to 25, wherein the method further comprises expelling at least a portion of the sample of microorganisms from the article into a liquid.

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