Zwitterion surface modifications for continuous sensors

Abstract

Devices are provided for measurement of an analyte concentration, e.g., glucose in a host. The device can include 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 a diffusion resistance domain configured to control a flux of the analyte therethrough. The diffusion resistance domain comprises one or more zwitterionic compounds and a base polymer comprising both hydrophilic and hydrophobic regions.

1 - 10 . (canceled) 
     
     
         11 . An implantable device for measurement of a glucose concentration in a host, the device comprising:
 a sensor configured to generate a signal indicative of a glucose concentration; and   a membrane located over the sensor, wherein the membrane comprises:
 a first domain configured to interface with tissue and/or a biological fluid, wherein the first domain is configured to reduce protein adsorption and cell adhesion, wherein the first domain comprises a zwitterion; and 
 a second domain comprising an enzyme configured to react with glucose. 
   
     
     
         12 . The device of  claim 11 , wherein the zwitterion is a betaine or a precursor or a derivative thereof. 
     
     
         13 . The device of  claim 12 , wherein an amount of the betaine or the precursor or the derivative thereof in the first domain is from about 0.1% wt. to about 50% wt. of the first domain. 
     
     
         14 . The device of  claim 12 , wherein an amount of the betaine or the precursor or the derivative thereof in the first domain is from about 10% wt to about 40% wt. of the first domain. 
     
     
         15 . The device of  claim 12 , wherein the betaine or the precursor or the derivative thereof comprise at least one compound selected from the group consisting of a carboxyl betaine compound, a sulfo betaine compound, a phosphor betaine compound, and derivatives thereof. 
     
     
         16 . The device of  claim 12 , wherein the betaine or the precursor or the derivative thereof comprises at least one compound selected from the group consisting of cocamidopropyl betaine, oleamidopropyl betaine, octyl sulfobetaine, caprylyl sulfobetaine, lauryl sulfobetaine, myristyl sulfobetaine, palmityl sulfobetaine, stearyl sulfobetaine, betaine (trimethylglycine), octyl betaine, phosphatidylcholine, glycine betaine, poly(carboxybetaine), poly(sulfobetaine), and derivatives thereof. 
     
     
         17 . The device of  claim 12 , wherein the betaine or the precursor or the derivative thereof comprises at least one compound selected from the group consisting of poly(carboxybetaine), poly(sulfobetaine), and derivatives thereof. 
     
     
         18 . The device of  claim 11 , wherein the zwitterion is selected from the group consisting of phosphorylcholine, phosphoryl ethanolamine, phosphatidyl ethanolamine, phosphoethanolamine, phosphatidyl serine, and precursors or derivatives thereof. 
     
     
         19 . The device of  claim 11 , wherein the enzyme is selected from the group consisting of glucose oxidase, glucose dehydrogenase, galactose oxidase, cholesterol oxidase, amino acid oxidase, alcohol oxidase, lactate oxidase, and uricase. 
     
     
         20 . The device of  claim 19 , wherein the enzyme is glucose oxidase. 
     
     
         21 . The device of  claim 11 , wherein the device is configured for continuous measurement of glucose concentration. 
     
     
         22 . An implantable device for measurement of a glucose concentration in a host, the device comprising:
 a sensor configured to generate a signal indicative of a glucose concentration; and   a membrane located over the sensor, wherein the membrane comprises:
 a first domain configured to interface with tissue and/or a biological fluid, wherein the first domain is configured to reduce protein adsorption and cell adhesion, wherein the first domain comprises at least one polyampholytic polymer; and 
 a second domain comprising an enzyme. 
   
     
     
         23 . The implantable device of  claim 22 , wherein the at least one polyampholytic polymer contains up to 0.1% wt charged monomers. 
     
     
         24 . The implantable device of  claim 22 , wherein the at least one polyampholytic polymer contains up to 0.5% wt charged monomers. 
     
     
         25 . The implantable device of  claim 22 , wherein the at least one polyampholytic polymer contains up to 1% wt charged monomers. 
     
     
         26 . The implantable device of  claim 22 , wherein the at least one polyampholytic polymer contains up to 5% wt charged monomers. 
     
     
         27 . The implantable device of  claim 22 , wherein the at least one polyampholytic polymer comprises a plurality of polyampholytic polymers that are crosslinked with each other. 
     
     
         28 . The implantable device of  claim 22 , wherein the at least one polymampholytic polymer comprises positively charged [2-(acryloyloxy)ethyl]trimethyl ammonium chloride (TMA) monomers. 
     
     
         29 . The implantable device of  claim 22 , wherein the at least one polymampholytic polymer comprises negatively charged 2-carboxy ethyl acrylate (CAA) monomers.