# US 10,307,722 B2 · Method for reducing the viscosity of a nanofibrillar cellulose hydrogel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,722 B2 - Document ID: US10307722B2 - Status: Granted - Kind: B2 - Application number: 15/538,515 - Filed: 2015-12-21 - Published: 2017-12-14 - Granted: 2019-06-04 - Earliest claimed: 2014-12-22 - Assignees: Upm-Kymmene Corporation - Applicants: UPM-Kymmene Corporation - Inventors: Markus Nuopponen; Isko Kajanto; Anne Meriluoto; Kari Luukko; Lauri Paasonen - Web page: https://patentgrep.com/patent/US10307722B2 ## CPC - B01J 13/0069: {Post treatment} - B01J 13/0056: {containing inorganic material and water} - C12N 1/22: Processes using, or culture media containing, cellulose or hydrolysates thereof - C12N 5/0018: {Culture media for cell or tissue culture (media for specific animal cell type C12N5/06)} - D21H 11/18: Highly hydrated, swollen or fibrillatable fibres - D21H 11/20: Chemically or biochemically modified fibres - C12N 2500/05: Inorganic components - C12N 2500/34: Sugars - C12N 2521/00: Culture process characterised by the use of hydrostatic pressure, flow or shear forces - C12N 2533/78: Cellulose - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - D21H: PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR ## Abstract The invention relates to a method for reducing the viscosity of a nanofibrillar cellulose hydrogel, wherein the method comprises mixing a nanofibrillar cellulose hydrogel with an aqueous growth medium for cell culture, wherein the aqueous growth medium contains one or more salts and optionally one or more sugars, using shearing forces so that a homogeneous dispersion is formed. The invention further relates to a dispersion comprising a nanofibrillar cellulose hydrogel and an aqueous growth medium for cell culture and to a use of an aqueous growth medium. ## Claims ### Claim 1 A method for reducing the viscosity of a nanofibrillar cellulose hydrogel, wherein the method comprises mixing a nanofibrillar cellulose hydrogel with an aqueous growth medium for cell culture, wherein the aqueous growth medium includes one or more salts and optionally one or more sugars, using shearing forces strong enough in order to disperse the nanofibrillar cellulose homogeneously in the mixture so that a homogeneous dispersion of the nanofibrillar cellulose is formed, wherein individual rafts of hydrogel are not observable visually or macroscopically in the homogeneous dispersion, the nanofibrillar cellulose hydrogel comprising about 0.05%-4% (w/w) of nanofibrillar cellulose. ### Claim 2 (depends on 1) The method according to claim 1, wherein the method comprises mixing the nanofibrillar cellulose hydrogel with the aqueous growth medium using an apparatus selected from the group consisting of a blender, a fluidizer, a disperser and a homogenizer. ### Claim 3 (depends on 1) The method according to claim 1, wherein the aqueous growth medium comprises at least about 1-400 meq/l of ions of one or more salts. ### Claim 4 (depends on 1) The method according to claim 1, wherein the dispersion of the nanofibrillar cellulose hydrogel and the aqueous growth medium comprises about 10-400 meq/l of ions of one or more salts. ### Claim 5 (depends on 1) The method according to claim 1, wherein the aqueous growth medium comprises about 0.1-500 mmol/l of one or more sugars. ### Claim 6 (depends on 1) The method according to claim 1, wherein the dispersion of the nanofibrillar cellulose hydrogel and the aqueous growth medium comprises 0.1-500 mmol/l of one or more sugars. ### Claim 7 (depends on 1) The method according to claim 1, wherein the nanofibrillar cellulose is native or anionic nanofibrillar cellulose. ### Claim 8 (depends on 1) The method according to claim 1, further comprising mixing the nanofibrillar cellulose hydrogel and the aqueous growth medium at a volume ratio in the range of about 9:1-1:9. ### Claim 9 (depends on 1) The method according to claim 1, further comprising mixing the nanofibrillar cellulose hydrogel and the aqueous growth medium to form a dispersion giving a pipetting error of less than 5% (v/v) upon pipetting. ### Claim 10 (depends on 1) The method according to claim 1, further comprising mixing the nanofibrillar cellulose hydrogel and the aqueous growth medium until the viscosity of the dispersion no longer decreases. ### Claim 11 A dispersion comprising a nanofibrillar cellulose hydrogel and an aqueous growth medium for cell culture, wherein the aqueous growth medium includes one or more salts and optionally one or more sugars, and wherein the nanofibrillar cellulose hydrogel is homogeneously dispersed in the aqueous growth medium and wherein individual rafts of hydrogel are not observable visually or macroscopically, wherein the dispersion comprises about 0.05%-2.5% (w/w) of nanofibrillar cellulose. ### Claim 12 (depends on 11) The dispersion according to claim 11, wherein the dispersion comprises about 10-400 meq/l of ions of one or more salts. ### Claim 13 (depends on 11) The dispersion according to claim 11, wherein the dispersion comprises about 0.1-500 mmol/l of one or more sugars. ### Claim 14 (depends on 11) The dispersion according to claim 11, wherein the dispersion comprises the nanofibrillar cellulose hydrogel and the aqueous growth medium at a volume ratio in the range of about 9:1-1:9. ### Claim 15 (depends on 11) The dispersion according to claim 11, wherein the dispersion has a Brookfield viscosity of up to 15000 mPa·s, as measured with a Brookfield viscometer at a temperature of 20° C., with a vane spindle and a measuring speed of 10 rpm. ### Claim 16 (depends on 11) The dispersion according to claim 11, wherein the Brookfield viscosity of the dispersion may be at least 10% lower than the Brookfield viscosity of the nanofibrillar cellulose hydrogel comprising nanofibrillar cellulose at the same concentration (w/w). ### Claim 17 (depends on 11) The dispersion according to claim 11, wherein the storage modulus of the dispersion is less or equal to about 200 Pa. ### Claim 18 (depends on 11) The dispersion according to claim 11, wherein the dispersion gives a pipetting error of less than 5% (v/v) upon pipetting. ### Claim 19 (depends on 11) The dispersion according to claim 11, wherein the nanofibrillar cellulose is native or anionic nanofibrillar cellulose. ### Claim 20 (depends on 11) A multiwell plate or a kit comprising the dispersion according to claim 11.