Interstitial fluid collection and constituent measurement

• US 7,001,343 B2
• Filed: 03/06/2003
• Issued: 02/21/2006
• Est. Priority Date: 10/13/1993
• Status: Expired due to Term

• Current Assignee: Integ Incorporated (Johnson & Johnson)
• Original Assignee: Integ Incorporated (Johnson & Johnson)
• Inventors: Knudson, Mark B., Erickson, Brian J., Hilgers, Michael E., Shapland, J. Edward, Hendrickson, Tracy A., Solomon, Frank A.
• Primary Examiner(s): Hindenburg, Max F.
• Assistant Examiner(s): SZMAL, BRIAN SCOTT
• Application Number:
  US10/384,106
• Publication Number:
  US 20030233055A1
• Time in Patent Office: 1,083 Days
• Field of Search: 600/573, 600/576, 600/578, 600/579, 600/581, 600/583, 600/584, 600/365, 606/181, 606/182
• US Class Current: 600/573
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters

Abstract

An apparatus and method is disclosed for obtaining and measuring constituents in a sample of body fluid. The apparatus includes a member which is sized to penetrate into at least the dermal layer of skin to collect a sample of body fluid located within the dermal layer.

Claims

1. A method for testing the glucose level in a patient having skin, the method comprising:

creating an opening in the skin but not through the skin;

extracting an interstitial fluid from a dermal layer of said skin without extracting a substantial portion of blood;

transporting the extracted interstitial fluid directly from the patient to a test site within a test apparatus; and

testing the glucose level of the interstitial fluid at the test site.

2. The method of claim 1 wherein the test apparatus includes a needle, and the creating an opening in the skin comprises penetrating the needle into, but not through, a dermal layer of the skin.

3. The method of claim 1 wherein the transporting the interstitial fluid comprises inserting a tube into the skin.

4. The method of claim 3 wherein the transporting the interstitial fluid further comprises exerting a capillary action on the interstitial fluid by means of the tube.

5. The method of claim 3 wherein the transporting the interstitial fluid comprises applying a negative pressure within the tube.

6. The method of claim 3 wherein the transporting the interstitial fluid comprises applying pressure to the skin adjacent the tube.

7. The method of claim 1 wherein the test site comprises a membrane.

8. The method of claim 1 wherein the test site comprises a reservoir.

9. The method of claim 1 wherein the testing the glucose level in the interstitial fluid comprises:

exposing the interstitial fluid to spectral radiation, the spectral radiation including a predetermined wavelength of light; and

determining whether the interstitial fluid absorbs the predetermined wavelength of light from the spectral radiation.

10. The method of claim 9 wherein the predetermined wavelength of light is in the infrared portion of the spectrum.

11. The method of claim 1 wherein the testing the glucose level in the interstitial fluid comprises electrochemical testing.

12. The method of claim 11 wherein the electrochemical testing comprises placing electrodes in electrical communication with the interstitial fluid.

13. The method of claim 1 wherein said testing the glucose level in the interstitial fluid comprises exposing the interstitial fluid to a chemical wherein the chemical changes color when exposed to glucose.