Method for formulating and immobilizing a matrix protein and a matrix protein for use in a sensor

• US 20050214741A1
• Filed: 05/04/2005
• Published: 09/29/2005
• 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, Montalvo, Rudolph A., Reghabi, Bahar, Zhang, Yanan
• Granted Patent: US 8,137,927 B2
• Time in Patent Office: Days
• US Class Current: 435/4
• 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

1-31. -31. (canceled)

32. A solidified 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 the combined protein component and cross-linking reagent is solidified into at least one pellet for disposing in a sensor.

33. A solidified protein material according to claim 32, wherein the protein component combined with a crosslinking reagent comprises a protein mixture that had been exposed to a vapor phase cross-linking process.

34. A solidified protein material according to claim 33, wherein the protein component comprises a protein component which had been incubated prior to the protein component having been exposed to the vapor phase cross-linking process.

35. A solidified protein material according to claim 33, wherein the protein component comprises a protein component which had been immersed in a cross-linking solution after the protein component had been exposed to the vapor phase cross-linking process.

36. A solidified protein material according to claim 32, wherein the protein component comprises a protein component which has been exposed to a vapor phase that is approximately 12.5% (w/w) glutaraldehyde for approximately 16 hours.

37. A solidified protein material according to claim 33, wherein the protein component comprises a protein component which had been incubated by maintaining the protein component at approximately room temperature for approximately two hours prior to the protein component having been exposed to the vapor phase cross-linking process.

38. A solidified protein material according to claim 33, wherein the protein component comprises a protein component which had been immersed in a cross-linking solution by submerging the protein mixture in a buffered solution that is approximately 2.5% (w/w) glutaraldehyde for approximately one hour after the protein solution had been exposed to the vapor phase cross-linking process.

39. A solidified protein material according to claim 32, wherein the protein component comprises glucose oxidase and human serum albumin.

40. A solidified protein material according to claim 32, wherein the cross-linking reagent is glutaraldehyde.

41. A solidified protein material according to claim 39, wherein the cross-linking reagent is glutaraldehyde.

42. A solidified protein material according to claim 32, wherein the cross-linking reagent is selected from a group consisting of glutaraldehyde, disuccinimidyl suberate (DSS), and 1-Ethyl-3 (3-Dimethylaminopropyl) Carbodiimide (EDC).

43. A solidified protein material according to claim 39, wherein the glucose oxidase has a concentration that is between approximately 67,000 U/ml and 150,000 U/ml.

44. A solidified protein material according to claim 43, 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.

45. A solidified protein material according to claim 32, 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.

46. A solidified protein material according to claim 32, wherein the at least one pellet is configured as at least one elongated structure having a dimension that is elongated relative to its other dimensions.

47. A solidified protein material according to claim 32, wherein the at least one pellet comprises a plurality of pellets that had been cut into pieces from a single continuous length of protein material.

48. A solidified protein material according to claim 46, wherein each elongated structure is semi-cylindrical in cross-section.

49. A solidified protein material according to claim 32, wherein the protein component comprises a protein component in which silicone has been added.

50. A solidified protein material according to claim 32, wherein silicon particles are included in the protein component, the volume of the silicone particles is less than 20% of the volume of the protein component.

53. A solidified protein material as recited in claim 32, wherein the solidified pellet is hard enough to maintain its shape without external forces.

51. An active protein for disposing in a sensor, the active protein comprising a solidified pellet composed of gluscose oxidase, human serum albumin, and a cross-linking reagent.

52. An active protein as recited in claim 51, wherein the active protein is solidified into at least one pellet before disposing in the sensor.

54. An active protein as recited in claim 51, wherein the solidified pellet is hard enough to maintain its shape without external forces.