Regeneration of biosensors

• US 20050112777A1
• Filed: 09/14/2004
• Published: 05/26/2005
• Est. Priority Date: 07/09/1997
• Status: Active Grant

• Current Assignee: Senzime AB (publ)
• Original Assignee: Thomas Carlsson
• Inventors: Carlsson, Thomas
• Granted Patent: US 7,285,197 B2
• Time in Patent Office: Days
• US Class Current: 436/183
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: Y10T 436/106664 Blood serum or blood plasma standard or control
• CPC Class Codes: Y10T 436/117497 with a continuously flowing sample or carrier stream

Abstract

The invention comprises a method of regenerating a biosensor. It involves passing a background flow of fluid without reactive components through the flow passage. At a selected point in time a sample aliquot is injected into said background flow. At a point in time when a signal from said sensor is obtained the flow rate of the background fluid is increased. The invention also comprises a system for continuous monitoring of analytes in a biological fluid, the system having increased life by virtue of inherent regeneration of sensors employed. It comprises a biosensor (26, 30, 32), a sampling device (4) for providing a sample of said biological fluid, and means (10, 15, 18, 24) for passing a flow of a background fluid through said flow passage at selectable flow rates, means (20, 50, 55) for injecting said sample into said flow of background fluid, and means (50, 55) for increasing the flow rate of said combined flow. Means for achieving a washing action at the signal generating portion are provided.

Claims

1-11. -11. (canceled)

12. A system for continuous monitoring of analytes in a biological fluid, the system having increased life by virtue of inherent regeneration of sensors employed, the system comprising:

(a) a biosensor of the type having a flow passage through which fluid is being passed at selectable flow rates, and a signal generating portion located in said flow passage and responsive to some component or property of a biological fluid;

(b) a sampling device for providing a sample of said biological fluid;

(c) means for passing a flow of a background fluid through said flow passage at controlled flow rates;

(d) means for injecting said sample into said flow of background fluid at selectable points in time to provide a combined flow;

(e) means for increasing the flow rate of said combined flow during passage of the sample through said flow passage in order to achieve a washing action on the signal generating portion; and

(f) means for providing a signal from said signal generating portion.

13. The system of claim 12, wherein said sampling device comprises a catheter insertable in a blood vessel of a human or an animal, and tubing connecting the catheter to the system.

14. The system of claim 12, wherein said means for passing a flow of a background fluid through said flow passage at controlled flow rates comprises a pump and appropriate tubing.

15. The system of claim 12, wherein said means for injecting said sample into said flow of background fluid, comprises a valve switchable between injection and waste disposal modes.

16. The system of claim 12, wherein said means for increasing the flow rate comprises a control unit programmed to respond to signals from said biosensor.

17. The system of claim 12, wherein said means for providing a signal from said signal generating portion comprises at least one thermistor.

18. The system of claim 12, further comprising a connector, for connecting said sampling device to said means for passing a flow of a background fluid through a control passage at controlled flow rates, the connector comprising;

a male and a female part;

a tube of a hard material such as steel having an inner diameter, and being inserted in the center of one of said male and female parts and protruding from an end surface of said part;

a catheter of a soft material inserted in the center of the other of said male and female parts and having an inner diameter substantially smaller than the inner diameter of said tube, and having an essentially flat end surface, wherein

the protruding end of said tube is ground such as to form a sharp circumferential edge and wherein

the positions of said tube said catheter in their respective male or female part, are such that when said male and female parts are connected, said sharp edge penetrates into said catheter, thereby forming a fluid tight connection.