# US 11,998,961 B2 · Endoscope cleaning with viscoelastic liquid > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,998,961 B2 - Document ID: US11998961B2 - Status: Granted - Kind: B2 - Application number: 17/285,897 - Filed: 2019-10-16 - Published: 2021-12-02 - Granted: 2024-06-04 - Earliest claimed: 2018-10-16 - Assignees: Saban Ventures Pty Limited - Applicants: Saban Ventures Pty Limited - Inventors: Alexander Galkin; Stefan Gebhardt; Ashwin Gopalan Nair; Brian Hingley; Joshua Storm Caley - Web page: https://patentgrep.com/patent/US11998961B2 ## CPC - A61B 1/125: {using fluid circuits} - B08B 9/0326: {Using pulsations} - A61B 90/70: Cleaning devices specially adapted for surgical instruments - A61L 2/18: Liquid substances - B08B 9/027: Cleaning the internal surfaces; Removal of blockages - B08B 9/032: by the mechanical action of a moving fluid, e.g. by flushing (B08B9/04 takes precedence {; by fluid jets mounted on cleaning devices B08B9/0433}) - C08F 220/56: Acrylamide; Methacrylamide - C08K 3/015: Biocides (macromolecular substances as carriers for biocide material A01N25/10) - C08L 33/02: Homopolymers or copolymers of acids; Metal or ammonium salts thereof - C11D 3/1213: {Oxides or hydroxides, e.g. Al2O3, TiO2, CaO or Ca(OH)2} - C11D 3/124: {Silicon containing, e.g. silica, silex, quartz or glass beads} - C11D 3/222: {Natural or synthetic polysaccharides, e.g. cellulose, starch, gum, alginic acid or cyclodextrin} - C11D 3/3765: {in liquid compositions} - C11D 3/386: Preparations containing enzymes {, e.g. protease or amylase} - A61B 1/122: {using cleaning tools, e.g. brushes} - A61L 2103/15: Laboratory, medical or dentistry appliances, e.g. catheters or sharps - A61L 2202/17: Combination with washing or cleaning means - B08B 2209/032: by the mechanical action of a moving fluid - C11D 2111/14: Hard surfaces - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - B08B: CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C11D: DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL ## Abstract The invention relates to compositions and methods for reducing biocontaminant (for example flesh, blood, mucous, faeces or biofilm) on a surface, such as an endoscope surface. The compositions are viscoelastic and of low lubricity, having the following properties at 21° C.: a rotational yield point between 140% strain and 300% strain; a peak viscosity between 550 Pa·s and 2000 Pa·s; an oscillatory flow point between 250 and 700% strain; and a coefficient of friction μ which has a maximum value (preferably 0.06 or greater) in the viscoelastic liquid's elastohydrodynamic region. ## Claims ### Claim 1 A method of reducing a biocontaminant on a surface contaminated therewith comprising contacting the surface with a viscoelastic liquid and flowing said viscoelastic liquid along said surface thereby to remove said biocontaminant from the surface, wherein the viscoelastic liquid has the following properties at 21° C.: a rotational yield point between 140% strain and 300% strain; a peak viscosity between 550 Pa·s and 2000 Pa·s; an oscillatory flow point between 250 and 700% strain; and a coefficient of friction μ which has a maximum value in the viscoelastic liquid's elastohydrodynamic region. ### Claim 2 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid has a coefficient of friction μ, of 0.06 or greater in its elastohydrodynamic region. ### Claim 3 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid is flowed under conditions of controlled shear rate and/or strain. ### Claim 4 (depends on 1) A method according to claim 1 wherein the surface comprises an interior surface of a medical instrument. ### Claim 5 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid is flowed continuously in a single direction. ### Claim 6 (depends on 1) A method according to claim 1 wherein the flow of the viscoelastic liquid is pulsed. ### Claim 7 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid has a flow rate such that an elastic modulus G′ of the viscoelastic liquid exceeds a viscous modulus G″ of the viscoelastic liquid. ### Claim 8 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid has a flow rate such that a shear rate of the viscoelastic liquid is below a flow point of the viscoelastic liquid. ### Claim 9 (depends on 1) A method according to claim 1 further including one or more pre-rinsing steps with water and/or enzymatic detergent. ### Claim 10 (depends on 1) A method according to claim 1 further including one or more post-rinsing steps with water and/or enzymatic detergent. ### Claim 11 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid comprises one or more polymers that are cationic, amphoteric, anionic or non-ionic, and wherein the one or more polymers are dispersed in a solvent. ### Claim 12 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid contains a dispersed high-surface area material that is inorganic or organic. ### Claim 13 (depends on 1) A method according to claim 1 wherein the viscoelastic liquid contains dispersed abrasive particles of inorganic and/or organic materials. ### Claim 14 (depends on 11) A method according to claim 11 wherein the one or more polymers comprise is carbomer, crosspolymer, acrylic polymer, Guar Gum, or their mixture. ### Claim 15 (depends on 11) A method according to claim 11 wherein the viscoelastic liquid has a solid content between 0.1 and 40%. ### Claim 16 (depends on 11) A method according to claim 11 wherein the one or more polymers are synthetic or natural. ### Claim 17 (depends on 16) A method according to claim 16 wherein the one or more polymers are Polyacrylate crosspolymer-6, carbomer, or mix of both. ### Claim 18 (depends on 11) A method according to claim 11 wherein a concentration of the one or more polymers is in the range of 0.1 to 20% by weight. ### Claim 19 (depends on 4) The method of claim 4 wherein the medical instrument comprises a lumen, and wherein the method further comprises directing the viscoelastic liquid along the interior surface of the lumen at a selected rate.