Culture media device and method of use
AssigneeMinnesota Mining and Manufacturing Company
InventorsRobert L. Nelson, Michael D. Crandall, Mary S. Ramos
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Abstract
A culture media device comprised of a body member including self-supporting substrate, and coated on its upper surface with a layer of water-based adhesive composition and a layer of a cold-water-soluble powder, is provided. The culture media device can also include an optional cover sheet, covering at least a portion of the body member, and an air-permeable membrane affixed to the upper surface of the substrate to allow for the growth of aerobic microorganisms. In addition, processes of making and using the culture media device are disclosed.
Claims36
A culture media device comprising:
- (a) a body member comprising a self-supporting substrate with upper and lower surfaces;
- (b) a layer of a water-based adhesive composition coated on the upper surface of the substrate, wherein the water-based adhesive composition comprises a water-insoluble adhesive, a non-inhibitory emulsifying agent, and at least one hydrophilic agent selected from the group consisting of a nutrient for growing microorganisms, a selective agent, and combinations thereof;
- and
- (c) cold-water-soluble powder comprising at least one gelling agent adhered uniformly to the layer of the water-based adhesive composition.
The culture media device according to claim 24, wherein the pressure-sensitive adhesive is a copolymer of isooctyl acrylate and acrylamide, or a copolymer of isooctyl acrylate and N-vinylpyrrolidone.
A method of making a culture media device useful for growing microorganisms comprising:
- (a) providing a body member comprising a self-supporting substrate with upper and lower surfaces, and a water-based adhesive composition comprising a water-insoluble adhesive, a noninhibitory emulsifying agent, water, and at least one hydrophilic agent selected from the group consisting of a nutrient for growing microorganisms, a selective agent, and combinations thereof;
- (b) coating a layer of the water-based adhesive composition on the upper surface of the substrate;
- and,
- (c) uniformly affixing cold-water-soluble powder comprising at least one gelling agent to the layer of the water-based adhesive composition.
A method of using a culture media device to detect microorganisms in an aqueous test sample comprising:
- (a) providing a culture media device comprising a body member including a self-supporting substrate with upper and lower surfaces, and a layer of a water-based adhesive composition coated on the upper surface of the substrate, wherein the water-based adhesive composition comprises a water-insoluble adhesive, a non-inhibitory emulsifying agent, and at least one hydrophilic agent selected from the group consisting of a nutrient for growing microorganisms, a selective agent, and combinations thereof, and wherein a uniform layer of a cold-water-soluble powder comprising at least one gelling agent is adhered to the layer of the water-based adhesive composition;
- (b) inoculating the culture media device with a predetermined volume of an aqueous test sample to form a reconstituted medium;
- (c) incubating the culture media device for a predetermined period of time;
- and,
- (d) counting the number of microorganism colonies growing on the reconstituted medium.
Dependencies are inferred from the claim text.