# US 2020/0399574 A1 · Water-reconstitutable culture medium resistant to liquefaction by microorganisms > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0399574 A1 - Document ID: US20200399574A1 - Status: Published application - Kind: A1 - Application number: 16/771,866 - Filed: 2018-12-12 - Published: 2020-12-24 - Earliest claimed: 2017-12-13 - Assignees: 3M Innovative Properties Company - Applicants: 3M Innovative Properties Company - Inventors: Jason W. Bjork; Sailaja Chandrapati - Web page: https://patentgrep.com/patent/US20200399574A1 ## CPC - C12M 23/20: {Material Coatings (immunocoatings C12M25/00)} - C08L 1/284: {with hydroxylated hydrocarbon radicals} - C12M 23/04: {Flat or tray type, drawers (C12M23/10, C12M23/12, C12M23/16 take precedence)} - C12M 23/24: {Gas permeable parts} - C12M 25/02: {Membranes; Filters (filters or filtration in general B01D24/00-B01D41/00)} - C12N 5/0068: {General culture methods using substrates (for specific animal cell type C12N5/06)} - G05F 1/59: including plural semiconductor devices as final control devices for a single load - H02M 3/157: with digital control - H02M 3/1584: {with a plurality of power processing stages connected in parallel} - H02M 1/0012: {Control circuits using digital or numerical techniques (in DC/DC converters H02M3/157, H02M3/33515; in DC-AC converters H02M7/53873)} - C12M: APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; {APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS} - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - G05F: SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) ## Abstract A device for growing microorganisms is provided. The device includes a body member comprising a self-supporting, waterproof substrate, a layer of adhesive disposed on the substrate, a powder adhered to the adhesive, a cover sheet adhered to the body member, and a dry composition including a mixture of hydroxypropylmethylcellulose and guar gum adhered to the cover sheet or the substrate. The powder comprises a cold-water-soluble gelling agent and one or more nutrient for growing microorganisms. The composition, when reconstituted with water, resists liquefaction by microorganisms A method of culturing microorganisms using the device is also provided. ## Claims ### Claim 1 A device for growing microorganisms, comprising: a body member comprising a self-supporting, water-proof substrate having upper and lower surfaces; a layer of adhesive disposed on the upper surface of the substrate, the adhesive being non-inhibitory to the growth of microorganisms; a cold-water-soluble powder adhered to the adhesive, the powder comprising: a cold-water-soluble gelling agent; one or more nutrients for growing microorganisms; a cover sheet having an inner-facing surface and an outer-facing surface, the cover sheet adhered to at least a portion of the body member; and a dry composition comprising a mixture of hydroxypropylmethylcellulose and guar gum adhered to the inner-facing surface of the cover sheet or the upper surface of bottom substrate; wherein the device includes a microbial growth zone disposed between the substrate and the cover sheet; wherein the microbial growth zone is free of matrixes that prevent visualization of bacterial colonies; wherein the cover sheet is adhered to the body member so that the upper surface of the substrate faces the inner-facing surface of the cover sheet. ### Claim 2 (depends on 1) The device of claim 1, wherein the cold-water-soluble gelling agent of the cold-water-soluble powder comprises guar gum and hydroxypropylmethylcellulose. ### Claim 3 (depends on 1) The device of claim 1, wherein the cold-water-soluble gelling agent of the cold-water-soluble powder consists essentially of guar gum and hydroxypropylmethylcellulose. ### Claim 4 (depends on 2) The device of claim 2, wherein the hydroxypropylmethylcellulose and guar gum are present in the cold-water-soluble gelling agent of the cold-water-soluble powder at a mass ratio of greater than or equal to one part hydroxypropylmethylcellulose to one part guar gum. ### Claim 5 (depends on 2) The device of claim 2, wherein the hydroxypropylmethylcellulose and guar gum are present in the cold-water-soluble gelling agent of the cold-water-soluble powder at a mass ratio of less than or equal to three parts hydroxypropylmethylcellulose to one part guar gum. ### Claim 6 (depends on 2) The device of claim 2, wherein the dry composition consists essentially of hydroxypropylmethylcellulose and guar gum. ### Claim 7 (depends on 6) The device of claim 6, wherein the hydroxypropylmethylcellulose and guar gum are present in the dry composition at a mass ratio of greater than or equal to one part hydroxypropylmethylcellulose to one part guar gum. ### Claim 8 (depends on 7) The device of claim 7, wherein the hydroxypropylmethylcellulose and guar gum are present in the dry composition at a mass ratio of less than or equal to three parts hydroxypropylmethylcellulose to one part guar gum. ### Claim 9 A device for growing microorganisms, comprising: a body member comprising a self-supporting, water-proof substrate having upper and lower surfaces; a cold-water-reconstitutable coating adhered to the upper surface of the substrate, the coating comprising: a cold-water-soluble gelling agent; one or more nutrients for growing microorganisms; a cover sheet having an inner-facing surface and an outer-facing surface, the cover sheet adhered to at least a portion of the body member; and a dry composition comprising a mixture of hydroxypropylmethylcellulose and guar gum adhered to the inner-facing surface of the cover sheet or the upper surface of bottom sheet; wherein the device includes a microbial growth zone disposed between the substrate and the cover sheet; wherein the microbial growth zone is free of matrixes that prevent visualization of bacterial colonies; wherein the cover sheet is adhered to the body member so that the upper surface of the substrate faces the inner-facing surface of the cover sheet. ### Claim 10 (depends on 9) The device of claim 9, wherein the cold-water-reconstitutable coating comprises guar gum and hydroxypropylmethylcellulose. ### Claim 11 (depends on 9) The device of claim 9, wherein the cold-water-reconstitutable coating consists essentially of guar gum and hydroxypropylmethylcellulose. ### Claim 12 (depends on 10) The device of claim 10, wherein the hydroxypropylmethylcellulose and guar gum are present in the cold-water-reconstitutable coating at a mass ratio of greater than or equal to one part hydroxypropylmethylcellulose to one part guar gum. ### Claim 13 (depends on 10) The device of claim 10, wherein the hydroxypropylmethylcellulose and guar gum are present in the cold-water-reconstitutable coating at a mass ratio of less than or equal to three parts hydroxypropylmethylcellulose to one part guar gum. ### Claim 14 (depends on 9) The device of any one of claim 9, wherein the dry composition consists essentially of hydroxypropylmethylcellulose and guar gum. ### Claim 15 (depends on 14) The device of claim 14, wherein the hydroxypropylmethylcellulose and guar gum are present in the dry composition at a mass ratio of greater than or equal to one part hydroxypropylmethylcellulose to one part guar gum. ### Claim 16 (depends on 14) The device of claim 14, wherein the hydroxypropylmethylcellulose and guar gum are present in the dry composition at a mass ratio of less than or equal to three parts hydroxypropylmethylcellulose to one part guar gum. ### Claim 17 (depends on 9) The device of any claim 9, further comprising a layer of adhesive disposed on the upper surface of the substrate, the adhesive being non-inhibitory to the growth of microorganisms; wherein the a cold-water-reconstitutable coating adhered to the adhesive layer.