ENZYME IMMOBILIZED ADHESIVE LAYER FOR ANALYTE SENSORS
Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The enzyme layer protects the enzyme and prevents it from leaching from the sensing membrane into a host or deactivating.
1 . A device for measurement of an analyte concentration, the device comprising:
a transcutaneous sensor configured to generate a signal associated with a concentration of an analyte; and
a sensing membrane located over the sensor, the sensing membrane comprising an enzyme layer, wherein the enzyme layer comprises an enzyme and an enzyme-layer polymer, wherein the polymer comprises one or more zwitterionic repeating units.
2 . The device of claim 1 , wherein the enzyme-layer polymer further comprises polyurethane and/or polyurea segments.
3 . The device of claim 1 , wherein the one or more zwitterionic repeating units comprise a betaine unit.
4 . The device of claim 1 , wherein the zwitterionic repeating units comprise a first betaine unit and a second betaine unit, wherein the first betaine unit is different from the second betaine unit.
5 . The device of claim 1 , wherein the zwitterionic repeating units are not located at an end group.
6 . The device of claim 1 , wherein the enzyme-layer polymer has a molecular weight from 10 kDa to 500,000 kDa.
7 . The device of claim 1 , wherein the enzyme-layer polymer has a molecular weight from 10 kDa to 100,000 kDa.
8 . The device of claim 1 , wherein the enzyme-layer polymer has a molecular weight from 100,000 kDa to 500,000 kDa.
9 . The device of claim 1 , wherein the enzyme-layer polymer has a polydispersity index of from about 1.4 to about 3.5.
10 . The device of claim 1 , wherein the enzyme-layer polymer has a contact angle of from about 10° to about 90°.
11 . The device of claim 1 , wherein the one or more zwitterionic repeating units is at least about 1 wt. % based on the total weight of the polymer.