Analytical element and measuring device and substrate quantification method using the same

• US 6,878,262 B2
• Filed: 08/13/2002
• Issued: 04/12/2005
• Est. Priority Date: 12/13/2000
• Status: Expired due to Term

• Current Assignee: PHC Holdings Corporation
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ikeda, Shin, Taniike, Yuko, Nankai, Shiro
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US10/216,716
• Publication Number:
  US 20030003524A1
• Time in Patent Office: 973 Days
• Field of Search: 205/777.5, 606/181, 600345-347, 204/403.01, 204/403.02, 204/403.14
• US Class Current: 205/777.5
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150213 Venting means
• CPC Class Codes: A61B 5/150297 for piercing devices, i.e. devices ready to be used for lancing or piercing for piercing elements A61B5/150282, for driving devices A61B5/15029
• 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 5/150412 Pointed piercing elements, e.g. needles, lancets for piercing the skin blade-like piercing elements A61B5/150442
• 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 5/15142 Devices intended for single use, i.e. disposable
• CPC Class Codes: A61B 5/15186 Devices loaded with a single lancet, i.e. a single lancet with or without a casing is loaded into a reusable drive device and then discarded after use; drive devices reloadable for multiple use
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: C12Q 1/005 involving specific analytes or enzymes including groups of enzymes, e.g. oxydases; C12Q1/004 takes precedence
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

The present invention provides an analytical element which is free from evaporation of a sample during measurement and therefore capable of quantifying a substrate using a very small amount of sample with high accuracy and which is free from scattering of the sample during and after the measurement and therefore hygienically excellent; and a measuring device and a substrate quantification method using the same. The analytical element comprises a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of the cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of the cavity, an opening communicating with the cavity and a member covering the opening.

Claims

1. An analytical element comprising a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of said cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said cavity, an opening communicating with said cavity and a member for covering said opening, and a driving unit coupled to the member, wherein the driving unit drives the member to cover and/or uncover the opening.

2. The analytical element in accordance with claim 1, wherein the member covering the opening is a puncture member.

3. The analytical element in accordance with claim 1, wherein the member covering the opening is transparent.

4. The analytical element in accordance with claim 1, wherein the member covering the opening also serves as the working electrode or the counter electrode.

5. The analytical element in accordance with one of claims 1 though 4, wherein the member covering the opening is provided with the reagent layer.

6. The analytical element in accordance with claim 1, further comprising a position controlling unit coupled to the driving unit, said position controlling unit controlling the position of said member.

7. An analytical element comprising:

a rod-like element body comprising an insulating member which has a depression for accommodating a sample at its side face in the vicinity of its tip end and a working electrode and a counter electrode arranged so as to be exposed to an inside of said depression;

a cover which covers the face of the element body having said depression, said cover having a groove along a longitudinal direction of said element body at a portion facing said depression;

a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said depression; and

a puncture member which moves in the longitudinal direction of the element body in said groove and sticks out of the tip end of the element body to puncture a subject, wherein a sample supply opening communicating with said depression is formed between the tip end of the element body and the cover, an air vent is formed at or above a position of the cover corresponding to said depression, and the puncture member is capable of substantially covering said depression.

8. An analytical element comprising:

an element body comprising an insulating base plate on which an electrode system comprising a working electrode and a counter electrode is formed and a cover member which covers said base plate and forms a sample supply pathway communicating with said electrode system between the cover and the base plate;

a reagent layer which comprises at least an oxidoreductase and is formed inside said sample supply pathway; and

a top cover, wherein said sample supply pathway extends from a sample supply port at one end of the element body to an air vent formed in the cover member, and the top cover is configured so as to be combined to the element body by sliding it in a direction perpendicular to the element body such that it closes said sample supply port and the air vent when it is in close contact with the element body.

9. A measuring device comprising:

an analytical element comprising a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of said cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said cavity, an opening communicating with said cavity and a member for covering said opening, and a driving unit coupled to the member, wherein the driving unit drives the member to cover and/or uncover the opening;

voltage application means for applying a voltage between said working electrode and said counter electrode; and

signal detecting means for detecting an electric signal between said working electrode and said counter electrode upon voltage application, wherein the amount of reaction between a substrate contained in the sample and said oxidoreductase is electrochemically detected to quantify said substrate.

10. The measuring device in accordance with claim 9, wherein the member of the analytical element covering the opening is detachable.

11. The measuring device in accordance with claim 9, wherein said analytical element further comprises a position controlling unit coupled to the driving unit, said position controlling unit controlling the position of said member.

12. A substrate quantification method comprising the steps of:

preparing an analytical element comprising a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of said cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said cavity, an opening communicating with said cavity and a member for selectively covering said opening, and a driving unit coupled to the member, wherein the driving unit drives the member to cover and/or uncover the opening;

supplying the sample to said analytical element to react a substrate contained in the sample with said oxidoreductase;

closing said opening;

applying a voltage between said working electrode and said counter electrode; and

detecting a change in electric signal between said working electrode and said counter electrode upon said voltage application.

13. The substrate quantification method in accordance with claim 12, wherein said analytical element further comprises a position controlling unit coupled to the driving unit, said position controlling unit controlling the position of said member.

14. An analytical element comprising a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of said cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said cavity, an opening communicating with said cavity and a member covering said opening, wherein the member covering the opening is a puncture member.

15. The analytical element in accordance with claim 14, wherein the member covering the opening is transparent.

16. The analytical element in accordance with claim 14, wherein the member covering the opening also serves as the working electrode or the counter electrode.

17. The analytical element in accordance with claim 14, wherein the member covering the opening is provided with the reagent layer.

18. An analytical element comprising a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of said cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said cavity, an opening communicating with said cavity and a member covering said opening, wherein the member covering the opening also serves as the working electrode or the counter electrode.

19. The analytical element in accordance with claim 18, wherein the member covering the opening is provided with the reagent layer.

20. An analytical element comprising a cavity for accommodating a sample, a working electrode and a counter electrode exposed to an inside of said cavity, a reagent layer which comprises at least an oxidoreductase and is formed inside or in the vicinity of said cavity, an opening communicating with said cavity and a member covering said opening, wherein the member covering the opening is provided with the reagent layer.