BIOSENSORS AND METHODS FOR MAKING AND USING THEM

• US 20100280347A1
• Filed: 05/20/2010
• Published: 11/04/2010
• Est. Priority Date: 10/18/2002
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Soundararajan, Gopikrishnan, Pendo, Shaun M., Shah, Rajiv, Hoss, Udo, Grovender, Eric A., Gottlieb, Rebecca K.
• Granted Patent: US 9,163,273 B2
• Time in Patent Office: Days
• US Class Current: 600/347
• CPC Class Codes: C12Q 1/006 for glucose

Abstract

Embodiments of the invention provide analyte sensors having optimized permselective membranes and methods for making and using such sensors. Embodiments of the invention also provide analyte sensors such as those having porous matrices coated with an analyte sensing composition and methods for making and using such sensors. Illustrative embodiments include electrochemical glucose sensors having glucose oxidase coatings.

Claims

1. A composition comprising a porous matrix having a surface coated with an immobilized enzyme, wherein the composition is implantable within a mammal.

2. The composition of claim 1, wherein the porous matrix is capable of acting as an electrode in an electrochemical sensor.

3. The composition of claim 1, wherein the enzyme is glucose oxidase, glucose dehydrogenase, lactate oxidase, hexokinase or lactate dehydrogenase.

4. The composition of claim 2, wherein the electrode consumes hydrogen peroxide in the electrochemical sensor.

5. The composition of claim 1, wherein the matrix comprises a micro-porous polymer.

6. The composition of claim 1, wherein the matrix comprises a micro-porous metal.

7. The composition of claim 1, wherein the matrix comprises a micro-porous a ceramic.

8. The composition of claim 1, wherein the porous matrix comprises a lattice of particles.

9. The composition of claim 8, wherein the particles are spherical.

10. The composition of claim 1, wherein the porous matrix is at least 1, 10, 100, or 1000 microns thick.

11. The composition of claim 1, wherein the porous matrix has a surface area that is at least 2, 4, 6, 8, 10, 12, 14, 16 or 18 times the surface area of a non-porous matrix of same dimensions.

12. The composition of claim 1, wherein the enzyme coated on the surface is in a coating layer having a thickness selected from the group consisting of less than 1, 0.5, 0.25 and 0.1 microns.

13. The composition of claim 1, wherein the porosity range of the porous matrix is 40%-99%.

25. The composition of claim 5, wherein the micro-porous polymer comprises a plurality of pores and further wherein at least one of the plurality of pores contains a biocompatible hydrophilic polymer that facilitates hydration of the composition.

26. The composition of claim 5, wherein the micro-porous polymer comprises a plurality of pores and further wherein at least one of the plurality of pores contains functionalized poly(dimethyl siloxane), functionalized poly(dimethyl siloxane) copolymer or a mixture of functionalized poly(dimethyl siloxane) and functionalized poly(dimethyl siloxane) copolymer of the second layer.

14. An analyte sensor apparatus for implantation within a mammal, the analyte sensor apparatus comprising a porous matrix having a surface coated with an immobilized enzyme.

15. The analyte sensor apparatus of claim 14, wherein:

the porous matrix comprises a working electrode; and

the immobilized enzyme is disposed within an analyte sensing layer disposed on the working electrode, such that the analyte sensing layer detectably alters the electrical current at the working electrode in the conductive layer in the presence of an analyte.

16. The analyte sensor apparatus of claim 15, further comprising an analyte modulating layer disposed on the analyte sensing layer, wherein the analyte modulating layer modulates the diffusion of the analyte therethrough.

17. The analyte sensor apparatus of claim 16, further comprising an adhesion promoting layer disposed on the analyte sensing layer, wherein the adhesion promoting layer promotes the adhesion between the analyte sensing layer and an analyte modulating layer disposed on the analyte sensing layer.

18. The analyte sensor apparatus of claim 16, further comprising a protein layer disposed between the analyte sensing layer and the analyte modulating layer.

19. The analyte sensor apparatus of claim 16, further comprising an interference rejection layer disposed between the surface of the working electrode and the analyte sensing layer.

20. The analyte sensor apparatus of claim 16, further comprising a cover layer disposed on at least a portion of the analyte modulating layer, wherein the cover layer further includes an aperture that exposes at least a portion of the analyte modulating layer to a solution comprising the analyte to be sensed.

21. The analyte sensor apparatus of claim 15, wherein the analyte sensing layer comprises an enzyme selected from the group consisting of glucose oxidase, glucose dehydrogenase, lactate oxidase, hexokinase and lactate dehydrogenase.

22. The analyte sensor apparatus of claim 21, wherein the analyte sensing layer further comprises a carrier protein in a substantially fixed ratio with the enzyme.

23. The analyte sensor apparatus of claim 22, wherein the enzyme and the carrier protein are distributed in a substantially uniform manner throughout the enzyme layer.

24. A kit comprising a container and, within the container, an analyte sensor apparatus according to claim 15 and instructions for using the analyte sensor apparatus.