# US 2022/0022786 A1 · Polycarbonate urea/urethane polymers for use with analyte sensors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0022786 A1 - Document ID: US20220022786A1 - Status: Published application - Kind: A1 - Application number: 17/496,527 - Filed: 2021-10-07 - Published: 2022-01-27 - Earliest claimed: 2016-06-06 - Assignees: Medtronic MiniMed, Inc. - Applicants: Medtronic MiniMed, Inc. - Inventors: Jenn-Hann Larry Wang - Web page: https://patentgrep.com/patent/US20220022786A1 ## CPC - A61B 5/14865: {invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors} - A61B 5/14532: {for measuring glucose, e.g. by tissue impedance measurement} - A61B 5/686: {Permanently implanted devices, e.g. pacemakers, other stimulators, biochips (A61B5/6861 takes precedence)} - C08G 18/4018: {Mixtures of compounds of group C08G18/42 with compounds of group C08G18/48} - C08G 18/44: Polycarbonates - C08G 18/5024: {containing primary and/or secondary amino groups} - C08G 18/61: Polysiloxanes - C08G 18/724: {Combination of aromatic polyisocyanates with (cyclo)aliphatic polyisocyanates} - C08G 18/73: acyclic - C08G 18/758: {containing two or more cycloaliphatic rings} - C08G 18/7671: {containing only one alkylene bisphenyl group} - C12Q 1/006: {for glucose} - A61B 5/14542: {for measuring blood gases (A61B5/14551 takes precedence)} - A61B 2505/07: Home care - A61B 2562/0285: Nanoscale sensors - A61B 2562/125: characterised by the manufacture of electrodes - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS - C12Q: MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS (immunoassay G01N33/53); COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES ## Abstract Embodiments of the invention provide compositions useful in analyte sensors as well as methods for making and using such compositions and sensors. In typical embodiments of the invention, the sensor is a glucose sensor comprising an analyte modulating membrane formed from a polymer composition having carbonate and aromatic isocyanate chains, a composition observed to provide such membranes with improved material properties such as enhanced thermal and hydrolytic stability. ## Claims ### Claim 1 A method of making an analyte sensor for implantation within a mammal comprising the steps of: providing a base layer; forming a conductive layer on the base layer, wherein the conductive layer includes a working electrode; forming an analyte sensing layer on the conductive layer, wherein the analyte sensing layer includes an oxidoreductase; forming an analyte modulating layer on the analyte sensing layer, wherein: the analyte modulating layer comprises a polyurea-urethane copolymer formed from a reaction mixture comprising: (a) a diisocyanate; (b) a hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine; (c) a siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus; and (d) a polycarbonate diol. ### Claim 2 (depends on 1) The method of claim 1, wherein the polyurea-urethane copolymer is formed from the reaction mixture selected to exhibit an improved thermal stability over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a comparative reaction mixture that does not include the polycarbonate diol; wherein said improved thermal stability over time comprises a loss of polyurea-urethane copolymer molecular weight after aging at 100% relative humidity (RH) at 60° C. over 6 days that is at least 10% less than the loss of molecular weight after aging at 100% relative humidity (RH) at 60° C. over 6 days that is observed in a polyurea-urethane copolymer molecular formed from a reaction mixture that does not include the polycarbonate diol. modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 3 (depends on 1) The method of claim 1, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit an improved resistance to degradation/damage caused by ebeam radiation and/or ethylene oxide as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 4 (depends on 1) The method of claim 1, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit an improved thermal stability over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 5 (depends on 1) The method of claim 1, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit an improved resistance to oxidation over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 6 (depends on 1) The method of claim 1, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit less deformation over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 7 (depends on 1) The method of claim 1, wherein: the analyte modulating layer comprises a polyurea-urethane copolymer formed from a reaction mixture comprising: (a) a diisocyanate present in amounts from 2% to 25% in the polyurea-urethane copolymer formed from the reaction mixture; (b) a hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine; (c) a siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus; and (d) a polycarbonate diol, wherein: the diisocyanate comprises a hexamethylene diisocyanate and/or a methylene diphenyl diisocyanate; the hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine comprises a polyetheramine; the siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus comprises a polydimethylsiloxane; and the polycarbonate diol comprises a poly(1,6-hexyl carbonate) diol and/or a or poly(1,6 hexyl-1,5 pentyl carbonate) diol. ### Claim 8 (depends on 1) The method of claim 1, wherein the analyte sensor is a glucose sensor that is implantable in interstitial fluid. ### Claim 9 (depends on 1) The method of claim 1, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit a greater uniform glucose permeability profile over time as compared to an equivalent analyte sensor having an analyte ### Claim 10 A method of making an analyte sensor for implantation within a mammal comprising the steps of: providing a base layer; forming a conductive layer on the base layer, wherein the conductive layer includes a working electrode; forming an analyte sensing layer on the conductive layer, wherein the analyte sensing layer includes an oxidoreductase; forming an analyte modulating layer on the analyte sensing layer, wherein: the analyte modulating layer comprises a polyurea-urethane copolymer formed from a reaction mixture comprising: (a) a diisocyanate; (b) a hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine; (c) a siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus; and (d) a polycarbonate diol, wherein: the diisocyanate comprises a hexamethylene diisocyanate and/or a methylene diphenyl diisocyanate; the hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine comprises a polyetheramine; the siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus comprises a polydimethylsiloxane; and the polycarbonate diol comprises a poly(1,6-hexyl carbonate) diol and/or a poly(1,6 hexyl-1,5 pentyl carbonate) diol; and the diisocyanate comprises: from 17% to 23% weight percent hexamethylene diisocyanate; and from 0% to 8.5% weight percent methylene diphenyl diisocyanate; and the polydimethylsiloxane comprises from 14% to 32% weight percent polydimethylsiloxane-A15; and the polycarbonate diol comprises from 7.5% to 19% weight percent poly(1,6-hexyl carbonate) diol. ### Claim 11 (depends on 10) The analyte sensor of claim 10, wherein the polyurea-urethane copolymer is formed from the reaction mixture selected to exhibit an improved thermal stability over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a comparative reaction mixture that does not include the polycarbonate diol; wherein said improved thermal stability over time comprises a loss of polyurea-urethane copolymer molecular weight after aging at 100% relative humidity (RH) at 60° C. over 6 days that is at least 10% less than the loss of molecular weight after aging at 100% relative humidity (RH) at 60° C. over 6 days that is observed in a polyurea-urethane copolymer molecular formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 12 (depends on 10) The method of claim 10, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit an improved resistance to degradation/damage caused by ebeam radiation and/or ethylene oxide as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 13 (depends on 10) The method of claim 10, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit an improved thermal stability over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 14 (depends on 10) The method of claim 10, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit an improved resistance to oxidation over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 15 (depends on 10) The method of claim 10, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit less deformation over time as compared to an equivalent analyte sensor having an analyte modulating layer formed from a reaction mixture that does not include the polycarbonate diol. ### Claim 16 (depends on 10) The method of claim 10, wherein: the analyte modulating layer comprises a polyurea-urethane copolymer formed from a reaction mixture comprising: (a) a diisocyanate present in amounts from 2% to 25% in the polyurea-urethane copolymer formed from the reaction mixture; (b) a hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine; (c) a siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus; and (d) a polycarbonate diol, wherein: the diisocyanate comprises a hexamethylene diisocyanate and/or a methylene diphenyl diisocyanate; the hydrophilic polymer comprising a hydrophilic diol or hydrophilic diamine comprises a polyetheramine; the siloxane having an amino, hydroxyl or carboxylic acid functional group at a terminus comprises a polydimethylsiloxane; and the polycarbonate diol comprises a poly(1,6-hexyl carbonate) diol and/or a or poly(1,6 hexyl-1,5 pentyl carbonate) diol. ### Claim 17 (depends on 10) The method of claim 10, wherein the polyurea-urethane copolymer is formed from a reaction mixture selected to exhibit a greater uniform glucose permeability profile over time as compared to an equivalent analyte sensor lacking the polyurea-urethane copolymer. ### Claim 18 (depends on 10) The method of claim 10, wherein the analyte sensor is a glucose sensor. ### Claim 19 (depends on 18) The method of claim 18, wherein the analyte sensor comprises a piercing member adapted to contact interstitial fluid. ### Claim 20 (depends on 10) The method of claim 10, wherein the conductive layer comprises a plurality of working electrodes and/or counter electrodes and/or reference electrodes; and the plurality of working, counter and reference electrodes are grouped together as a unit and positionally distributed on the conductive layer in a repeating pattern of units.