Particle-containing membrane and particulate electrode for analyte sensors

Abstract

Systems and methods of use involving sensors having a particle-containing domain 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 . A system for measuring an analyte concentration in a host, the system comprising:
 a working electrode configured to be implanted in a host, wherein the electrode comprises rhodium;   a membrane disposed over the electrode, wherein the membrane comprises an enzyme; and   sensor electronics configured to generate a signal indicative of a concentration of the species in the host.   
     
     
         22 . The system of  claim 21 , wherein the sensor electronics are configured to apply a potential of from about 0.1V to about 0.8V is applied to the working electrode. 
     
     
         23 . The system of  claim 22 , wherein the sensor electronics are configured to apply a potential of from about 0.3V to about 0.7V to the working electrode. 
     
     
         24 . The system of  claim 23 , wherein the sensor electronics are configured to apply a potential of from about 0.3V to about 0.5V to the working electrode. 
     
     
         25 . The system of  claim 24 , wherein the potential applied is constant. 
     
     
         26 . The system of  claim 22 , wherein potential applied is cyclical, pulsed, intermittent, variable, or a combination thereof. 
     
     
         27 . The system of  claim 21 , wherein the membrane comprises polyurethane. 
     
     
         28 . The system of  claim 21 , where the analyte is glucose. 
     
     
         29 . The system of  claim 21 , wherein the analyte is lactate. 
     
     
         30 . The system of  claim 21 , wherein the enzyme is glucose oxidase. 
     
     
         31 . The system of  claim 21 , wherein the working electrode comprises conductive particles that form a network and function as an array of microelectrodes. 
     
     
         32 . The system of  claim 21 , wherein the rhodium is disposed on a substrate. 
     
     
         33 . The system of  claim 32 , wherein the substrate is formed of a metal. 
     
     
         34 . The system of  claim 33 , wherein the metal is platinum. 
     
     
         35 . The system of  claim 32 , wherein the substrate is formed of a dielectric material. 
     
     
         36 . The system of  claim 35 , wherein the dielectric material is a polymer.