Molded protein material in form of pellet for sensor

• US 8,137,927 B2
• Filed: 05/04/2005
• Issued: 03/20/2012
• Est. Priority Date: 10/23/2001
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Shah, Rajiv, Reghabi, Bahar, Montalvo, Rudy, Zhang, Yanan
• Primary Examiner(s): NAFF, DAVID M
• Application Number:
  US11/122,172
• Publication Number:
  US 20050214741A1
• Time in Patent Office: 2,512 Days
• Field of Search: None
• US Class Current: 435/25
• CPC Class Codes: C07K 1/1077 by covalent attachment of residues other than amino acids or peptide residues, e.g. sugars, polyols, fatty acids
• CPC Class Codes: C12Q 1/54 involving glucose or galactose
• CPC Class Codes: Y10S 435/817 Enzyme or microbe electrode

Abstract

A method for formulating and immobilizing a protein and a protein matrix formed by the method. The protein matrix preparation method results in a physically and chemically stable protein matrix that has low swelling, non-leaching, high activity, and high mechanical strength properties. The method includes cross-linking and hardening the protein mixture and using a mold to form a protein into a desired shape and size.

Claims

1. A molded protein material for a sensor comprising:

a protein component comprising at least one protein, the protein component being combined with a cross-linking reagent, wherein said molded protein material is in the form of a pellet.

2. The molded protein material of claim 1, comprising a protein component that has been exposed to a vapor phase cross-linking process.

3. The molded protein material of claim 2, comprising a protein component that has been incubated prior to the protein component having been exposed to the vapor phase cross-linking process.

4. The molded protein material of claim 2, comprising a protein component which has been immersed in a cross-linking solution after exposure to the vapor phase cross-linking process.

5. The molded protein material of claim 1, comprising a protein component that has been exposed to a vapor phase that is approximately 12.5% (w/w) glutaraldehyde for approximately 16 hours.

6. The molded protein material of claim 2, comprising a protein component that has been maintained at approximately room temperature for approximately two hours prior to exposure to the vapor phase cross-linking process.

7. The molded protein material of claim 2, comprising a protein component that has been immersed in a cross-linking solution by submerging in a buffered solution that is approximately 2.5% (w/w) glutaraldehyde for approximately one hour, after exposure to the vapor phase cross-linking process.

8. The molded protein material of claim 1, wherein the protein component comprises glucose oxidase and human serum albumin.

9. The molded protein material of claim 1, wherein the cross-linking reagent comprises glutaraldehyde.

10. The molded protein material of claim 8, wherein the cross-linking reagent comprises glutaraldehyde.

11. The molded protein material of claim 1, wherein the cross-linking reagent is selected from a group consisting of glutaraldehyde, disuccinimidyl suberate (DSS), and 1-Ethyl-3 (3-Dimethylaminopropyl) Carbodiimide (EDC).

12. The molded protein material the claim 8, wherein the glucose oxidase has a concentration that is between about 67,000 U/ml and about 150,000 U/ml.

13. The molded protein material of claim 12, wherein the human serum albumin has a concentration that is between about 23% (w/v) and about 32.5% (w/v) of the combined protein component and cross-linking agent.

14. The molded protein material of claim 1, wherein said pellet is semi-cylindrical shaped.

15. The molded protein material according to claim 1, wherein the protein component further comprises silicone particles.

16. The molded protein material of claim 15, wherein the protein comprises less than about 20% silicon particles by volume.

17. The molded protein material of claim 1, wherein the protein material is molded into a pellet sized to be a line-to-line fit for a sensor housing.

18. The molded protein material of claim 1, wherein the protein material is molded into a pellet slightly oversized with respect to a sensor housing so as to fit snugly therein.

19. The molded protein material of claim 1, wherein the shape of the protein material is determined by molding, followed by cutting the molded protein material.

20. The molded protein material of claim 1, wherein said protein material is in the form of a pellet having a rectangular cross-section.

21. The molded protein material of claim 1, wherein said protein material is in the form of a pellet having a semi-circular cross-section.

22. The molded protein of claim 1, wherein the pellet has a three-dimensional shape corresponding to three dimensions of a shape of a mold in which the pellet was formed.

23. A molded protein material for disposing in a sensor, said molded protein material formed into a pellet by hardening the same inside and according to dimensions of a mold, and comprising of glucose oxidase, human serum albumin, and a cross-linking reagent.

24. The protein material as recited in claim 23, wherein the protein material is solidified into a pellet before disposing in the sensor.

25. The molded protein material as recited in claim 23, wherein the pellet has a three-dimensional shape corresponding to three dimensions of a shape of the mold in which the pellet was formed.

26. A molded protein material for a sensor comprising:

a protein component comprising at least one protein, the protein component being

combined with a cross-linking reagent, wherein said molded protein material is in the form of a pellet

wherein the protein component comprises glucose oxidase and human serum albumin;

wherein the human serum albumin has a concentration that is between approximately 23% (w/v) and 32.5% (w/v) of the combined protein component and cross-linking agent.