Analyte sensors and methods of manufacturing same
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.
1. A continuous analyte sensor configured for in vivo use, the continuous analyte sensor comprising:
an elongated conductive body comprising a first electrode comprising an electroactive surface, wherein the elongated conductive body further comprises a second electrode; and
a membrane covering at least a portion of the first electrode;
wherein the continuous analyte sensor has a yield strength at least 60 ksi, wherein the continuous analyte sensor has a fatigue life of at least 20 cycles of flexing 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 the second electrode and covering at least a portion of the insulating layer, and a membrane covering at least a portion the first 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 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 70 A to about 55 C.
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.
21. The continuous analyte sensor of claim 1 , having a fatigue life of at least 60 cycles of flexing of from about 45° to about −45° at a bend radius of about 0.031-inches.
22. The continuous analyte sensor of claim 1 , having a fatigue life of at least 65 cycles of flexing of from about 45° to about −45° at a bend radius of about 0.031-inches.
23. The continuous analyte sensor of claim 1 , wherein the elongated conductive comprises an insulator separating the first electrode from the second electrode.
24. The continuous analyte sensor of claim 1 , wherein the elongated conductive body has a yield strength from about 60 kPsi to about 319 kPsi.
25. The continuous analyte sensor of claim 1 , wherein the elongated conductive body has a Young's modulus from about 160GPa to about 220GPa.
26. The continuous analyte sensor of claim 1 , wherein the elongated conductive body is non-planar.
27. The continuous analyte sensor of claim 1 , wherein the first electrode is a working electrode.
28. The continuous analyte sensor of claim 1 wherein the second electrode is a reference electrode and/or counter electrode.
29. The continuous analyte sensor of claim 1 , wherein the reference electrode is formed of pad printed silver-containing material.
30. The continuous analyte sensor of claim 1 , wherein the membrane comprises polyurethane and an enzyme configured to react with glucose.
31. The continuous analyte sensor of claim 30 , wherein the polyurethane comprises polyurethaneurea.
32. The continuous analyte sensor of claim 1 , wherein the elongated conductive body has a planar shape.
33. The continuous analyte sensor of claim 1 , wherein the elongated conductive body has a wire-shaped structure.