Hydrogel composition for measuring glucose flux

• US 7,150,975 B2
• Filed: 08/18/2003
• Issued: 12/19/2006
• Est. Priority Date: 08/19/2002
• Status: Active Grant

• Current Assignee: LifeScan IP Holdings, LLC
• Original Assignee: Animas Technologies LLC (Johnson & Johnson)
• Inventors: Tamada, Janet A., Tierney, Michael J., Williams, Stephen C.
• Primary Examiner(s): GITOMER, RALPH J
• Application Number:
  US10/643,631
• Publication Number:
  US 20040087671A1
• Time in Patent Office: 1,219 Days
• Field of Search: 435/14, 604/20, 600/345, 600/347, 600/365, 607/153
• US Class Current: 435/14
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61N 1/0436 Material of the electrode
• CPC Class Codes: A61N 1/044 Shape of the electrode
• CPC Class Codes: A61N 1/325 for iontophoresis, i.e. transfer of media in ionic state by an electromotoric force into the body electrodes for external use A61N1/0428
• CPC Class Codes: C08J 3/075 Macromolecular gels

Abstract

The present invention relates to compositions for use in analyte monitoring devices. These compositions are useful to increase the flux of analyte across skin, tissue or mucosal surfaces. The compositions include hydrogels and collection reservoir systems comprising ionically conductive materials. The present invention also includes methods of making/manufacturing hydrogels or collection reservoir systems, collection assemblies comprising the hydrogels, electrode assemblies in combination with the hydrogels or collection reservoir systems, and methods of using the same.

Claims

1. A hydrogel composition for measuring glucose flux, said hydrogel composition comprising:

a hydrophilic compound which forms a gel in the presence of water, an electrolyte, a phosphate buffer present at a concentration of between about 125 mM and about 500 mM, and a pH of between about pH 6.5 to about pH 8.5, wherein the glucose flux into the hydrogel is at least 0.65 nmol/cm^2·

hr.

2. The hydrogel of claim 1, wherein the hydrophilic compound is selected from the group consisting of polyethylene oxide, polyvinyl alcohol, polyacrylic acid, and polyvinyl pyrrolidone, and co-polymers thereof.

3. The hydrogel composition of claim 1, wherein said hydrophilic compound comprises polyethylene oxide.

4. The hydrogel composition of claim 1, wherein said hydrophilic compound is a polymer, and said polymer is present at a weight percent of between about 0.5% to about 40%.

5. The hydrogel composition of claim 1, wherein said pH is between about pH 7 to about pH 8.

6. The hydrogel composition of claim 1, wherein the hydrogel further comprises a cross-linking agent.

7. The hydrogel composition of claim 6, wherein said cross-linking agent is present at a weight percent of from about 0.001% to about 2%.

8. The hydrogel composition of claim 7, wherein said cross-linking agent is N,N′

-methylenebisacrylamide.

9. The hydrogel composition of claim 1, wherein said hydrogel is treated with Electron-beam radiation to promote cross-linking within the hydrogel.

10. The hydrogel composition of claim 1, wherein said phosphate buffer comprises monobasic and dibasic phosphate.

11. The hydrogel composition of claim 10, wherein said monobasic and dibasic phosphate comprise counter ions and said counter ions are selected from the group consisting of sodium counter ions, potassium counter ions, and mixtures thereof.

12. The hydrogel composition of claim 11, wherein for said monobasic and dibasic phosphate the counter ion is potassium.

13. The hydrogel composition of claim 1, wherein said electrolyte is a chloride salt.

14. The hydrogel composition of claim 13, wherein said chloride salt is present at a weight percent of between about 0.25% to about 2%.

15. The hydrogel composition of claim 13, wherein said chloride salt is selected from the group consisting of sodium chloride, potassium chloride, and mixtures thereof.

16. The hydrogel composition of claim 15, wherein said chloride salt is potassium chloride.

17. The hydrogel composition of claim 1, wherein said hydrogel further comprises an enzyme.

18. The hydrogel composition of claim 17, wherein said analyte is glucose and said enzyme comprises glucose oxidase.

19. The hydrogel composition of claim 1, wherein the hydrogel further comprises a biocide.

20. The hydrogel composition of claim 19, wherein said biocide is selected from the group consisting of chlorinated hydrocarbons, organometallics, metallic salts, organic sulfur compounds, phenolic compounds, quaternary ammonium compounds, surfactants, membrane-disrupting agents, and combinations thereof.

21. The hydrogel composition of claim 19, wherein said biocide is undecylenic acid or a salt thereof.