Analyte sensors having a signal-to-noise ratio substantially unaffected by non-constant noise

Abstract

Systems and methods of use involving sensors having a signal-to-noise ratio that is substantially unaffected by non-constant noise are provided for continuous analyte measurement in a host. In some embodiments, a continuous analyte measurement system is configured to be wholly, transcutaneously, intravascularly or extracorporeally implanted.

1 - 20 . (canceled) 
     
     
         21 . An electrochemical continuous glucose sensor configured for implantation in a host, the glucose sensor comprising:
 an electrode configured to measure a signal indicative of a glucose concentration of a host; and   a membrane covering at least a portion of the electrode, wherein the membrane comprises a first domain configured to reduce passage of an interfering species therethrough and a second domain comprising an enzyme configured to react with glucose, wherein the first domain is configured to trap interfering species having a molecular weight equal to or greater than a molecular weight of acetaminophen and configured to prevent the interfering species from reaching the electrode, wherein the first domain is positioned between the second domain and the electrode.   
     
     
         22 . The glucose sensor of  claim 21 , wherein the molecular weight is about 151 Daltons. 
     
     
         23 . The glucose sensor of  claim 21 , wherein the interfering species has an oxidation potential that substantially overlaps with an oxidation potential of a measured species indicative of the concentration of the analyte. 
     
     
         24 . The glucose sensor of  claim 23 , wherein the measured species is a product of an enzymatic reaction between glucose and an enzyme and is measured by the electrode. 
     
     
         25 . The glucose sensor of  claim 21 , wherein the glucose sensor has a sensitivity to glucose of from about 25 pA/mg/dL to about 500 pA/mg/dL. 
     
     
         26 . The glucose sensor of  claim 21 , wherein the membrane further comprises a third domain configured to reduce a flux of glucose therethough. 
     
     
         27 . The glucose sensor of  claim 26 , wherein the third domain comprises a product of a reaction of an isocyanate compound with a compound comprising a hydroxyl group and/or a compound comprising an amine group. 
     
     
         28 . The glucose sensor of  claim 27 , wherein the product is polyurethane. 
     
     
         29 . The glucose sensor of  claim 27 , wherein the product is polyurea. 
     
     
         30 . The glucose sensor of  claim 27 , wherein the product is polyurethaneurea.