Method and device for sampling and analyzing interstitial fluid and whole blood samples

• US 6,939,312 B2
• Filed: 06/10/2002
• Issued: 09/06/2005
• Est. Priority Date: 03/27/2000
• Status: Expired due to Fees

• Current Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Hodges, Alastair, Chambers, Garry, Chatelier, Ron
• Primary Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US10/166,487
• Publication Number:
  US 20020177788A1
• Time in Patent Office: 1,184 Days
• Field of Search: 600/309, 600/322, 600/345, 600/347, 600/365, 600/576, 600/578, 600/580, 600/582, 600/584, 606/181, 435/4, 435/7.1, 435/14, 435/69.6, 422/50, 422/55, 422/68.1, 422/101, 422/102, 436/68, 204/403, 738/63, 738/640.1, 738/640.2, 738/645.1, 738/646.2
• US Class Current: 600/583
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157 disposable multilayered or laminated electrodes G01N27/307; details of handling chemical test elements G01N33/4875
• 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 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150213 Venting means
• CPC Class Codes: A61B 5/150221 Valves
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/150389 Hollow piercing elements, e.g. canulas, needles, for piercing the skin
• CPC Class Codes: A61B 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/15105 Purely manual piercing, i.e. the user pierces the skin without the assistance of any driving means or driving devices
• CPC Class Codes: A61B 5/15113 Manually triggered, i.e. the triggering requires a deliberate action by the user such as pressing a drive button
• CPC Class Codes: A61B 5/15117 comprising biased elements, resilient elements or a spring, e.g. a helical spring, leaf spring, or elastic strap
• CPC Class Codes: A61B 5/15142 Devices intended for single use, i.e. disposable
• CPC Class Codes: A61B 5/1519 comprising driving means, e.g. a spring, for propelling the piercing unit

Abstract

The invention disclosed in this application is a method and device for combining the sampling and analyzing of sub-dermal fluid samples, e.g., interstitial fluid or whole blood, in a device suitable for hospital bedside and home use. It is applicable to any analyte that exists in a usefully representative concentration in the fluid, and is especially suited to the monitoring of glucose.

Claims

1. A fluid sampling device, said fluid sampling device comprising:

a test strip comprising;

a penetration probe having a penetrating end and a communicating end;

an electrochemical analysis chamber having a first volume, said electrochemical analysis chamber further comprising a working electrode and a counter/reference electrode;

a pre-chamber integrated between said communication penetration probe and said analysis chamber, said pre-chamber having a second volume, wherein said second volume is larger than said first volume such that said analysis chamber exerts a greater capillary force than said pre-chamber;

a releasable actuator adapted to receive said test strip, wherein said releasable actuator is capable of supplying a force sufficient to cause said penetration probe to penetrate a dermal layer of a user'"'"' skin; and

an interface for communication with a meter.

2. A fluid sampling device according to claim 1 wherein said fluid sampling device is adapted to limit the penetration of said penetrating end into said dermal layer to a depth of less than approximately 2 mm.

3. A fluid sampling device according to claim 2 wherein said fluid sampling device is adapted to limit the penetration of said penetrating end into said dermal layer to a depth of approximately 1.5 mm.

4. A fluid sampling device according to claim 1 wherein said penetrating end of said penetration probe comprises two sheets in substantial registration, wherein each of said sheets has a sharply pointed protrusion.

5. A fluid sampling device according to claim 4 wherein said two sheets are separated by a distance of between 10 micrometers and 1 millimeter.

6. A fluid sampling device according to claim 1 wherein said first volume is less than 1.5 microliters.

7. A fluid sampling device according to claim 6 wherein said first volume is between 0.02 microliters and 1.5 microliters.

8. A fluid sampling device according to claim 7 wherein said first volume is between 0.1 microliters and 0.5 microliters.

9. A fluid sampling device according to claim 1 wherein said analysis chamber includes at least one material adapted to increase the capillary force exerted by said analysis chamber.

10. A fluid sampling device according to claim 9 wherein one or more walls of said analysis chamber is coated with a hydrophilic material to encourage the flow of fluid sample into the analysis chamber.

11. The method of claim 10, wherein the hydrophilic material is selected from the group consisting of:

polyethylene glycol, polyvinylpyrrolidone, a surfactant, a hydrophilic block copolymer, and polyacrylic acid.

12. A fluid sampling device according to claim 1 wherein one or more walls of said analysis chamber is coated with a reagent material to react with interfering substances.