Analyte sensors and methods of manufacturing same

Abstract

Analyte sensors and methods of manufacturing same are provided, including analyte sensors comprising multi-axis flexibility. For example, a multi-electrode sensor system 800 comprising two working electrodes and at least one reference/counter electrode is provided. The sensor system 800 comprises first and second elongated bodies E 1 , E 2 , each formed of a conductive core or of a core with a conductive layer deposited thereon, insulating layer 810 that separates the conductive layer 820 from the elongated body, a membrane layer deposited on top of the elongated bodies E 1 , E 2 , and working electrodes 802′, 802 ″ formed by removing portions of the conductive layer 820 and the insulating layer 810 , thereby exposing electroactive surface of the elongated bodies E 1 , E 2.

What is claimed is: 
     
         1 . A continuous analyte sensor configured for in vivo use, the continuous analyte sensor comprising:
 an elongated conductive body comprising a working electrode; and   a membrane covering at least a portion of the working electrode;   wherein the continuous analyte sensor has a fatigue life of at least 20 cycles of flexing of from about 45° to about −45° at a bend radius of about 0.031-inches.   
     
     
         2 . The continuous analyte sensor of  claim 1 , wherein the elongated conductive body comprises an elongated core, an insulating layer covering at least a portion of the elongated core, a conductive layer comprising a reference electrode or a counter electrode and covering at least a portion of the insulating layer, and a membrane covering at least a portion the working electrode. 
     
     
         3 . The continuous analyte sensor of  claim 2 , wherein the elongated core comprises an elongated body and a layer of conductive material covering at least a portion of the elongated body. 
     
     
         4 . The continuous analyte sensor of  claim 3 , wherein the elongated body comprises at least one material selected from the group consisting of stainless steel, titanium, tantalum, and a polymer. 
     
     
         5 . The continuous analyte sensor of  claim 3 , wherein the layer of conductive material covering at least a portion of the elongated body comprises a conductive material selected from the group consisting of platinum, platinum-iridium, gold, palladium, iridium, alloys thereof, graphite, carbon, and a conductive polymer. 
     
     
         6 . The continuous analyte sensor of  claim 2 , wherein the conductive layer comprising the reference electrode or the counter electrode comprises a silver-containing material. 
     
     
         7 . The continuous analyte sensor of  claim 6 , wherein the silver-containing material has a particle size associated with a maximum particle dimension that is less than about 100 microns. 
     
     
         8 . The continuous analyte sensor of  claim 7 , wherein the silver-containing material has a particle shape that is substantially spherical. 
     
     
         9 . The continuous analyte sensor of  claim 2 , wherein the insulating layer comprises at least one polymer selected from the group consisting of polyurethane and polyimide. 
     
     
         10 . The continuous analyte sensor of  claim 2 , wherein a ratio of a thickness of the conductive layer to a thickness of insulating layer is from about 1:5 to about 1:1. 
     
     
         11 . The continuous analyte sensor of  claim 2  wherein the conductive material is a silver-containing material. 
     
     
         12 . The continuous analyte sensor of  claim 1 , wherein the membrane comprises a polymer having a Shore hardness of from about 70A to about 55C. 
     
     
         13 . The continuous analyte sensor of  claim 1 , having an ultimate tensile strength of from about 80 kPsi to about 500 kPsi. 
     
     
         14 . The continuous analyte sensor of  claim 1 , having an ultimate tensile strength of from about 150 kPsi to about 280 kPsi. 
     
     
         15 . The continuous analyte sensor of  claim 1 , having a fatigue life of at least 1,000 cycles of flexing of from about 28° to about 110° at a bend radius of about 0.125-inches. 
     
     
         16 . The continuous analyte sensor of  claim 1 , which is configured for multi-axis bending. 
     
     
         17 . The continuous analyte sensor of  claim 16 , wherein the multi-axis bending is associated with flexing in at least three directions. 
     
     
         18 . The continuous analyte sensor of  claim 1 , wherein the elongated conductive body has a diameter of from about 50 microns to about 250 microns. 
     
     
         19 . The continuous analyte sensor of  claim 1 , having a fatigue life of at least 40 cycles of flexing of from about 45° to about −45° at a bend radius of about 0.031-inches. 
     
     
         20 . The continuous analyte sensor of  claim 1 , having a fatigue life of at least 50 cycles of flexing of from about 45° to about −45° at a bend radius of about 0.031-inches.