Measuring instrument provided with solid component concentrating means

• US 7,201,042 B2
• Filed: 10/30/2003
• Issued: 04/10/2007
• Est. Priority Date: 11/01/2002
• Status: Active Grant

• Current Assignee: ARKRAY, Inc
• Original Assignee: ARKRAY, Inc
• Inventors: Yamaoka, Hideaki, Katsuki, Koji
• Primary Examiner(s): CYGAN, MICHAEL T
• Application Number:
  US10/533,602
• Publication Number:
  US 20060042361A1
• Time in Patent Office: 1,258 Days
• Field of Search: 204/403.11, 204/403.01, 204/403.06, 73/617.1, 73/645.6, 738/655, 324/71.4, 324/71.1, 324/449
• US Class Current: 73/61.71
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• 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: C12Q 1/006 for glucose
• 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 relates to a measuring instrument (1) comprising a channel (60) for moving a sample liquid (BL) containing a solid component (B1) and providing a liquid reaction field and first and second electrodes (31, 32) which are used to apply voltage to the liquid reaction field. The first electrode (31) has an electron transfer interface (31a) for transferring electrons between it and the liquid reaction field when voltage is applied to the liquid reaction field via the first and second electrodes (31, 32). The measuring instrument (1) comprises concentrating means (51) for increasing the concentration of solid components at portions thereof which contact the electron transfer interface (31a) in the liquid reaction field. The concentrating means (51) preferably comprises a water-absorbing layer containing an absorbent polymer material.

Claims

1. A measuring instrument comprising:

a channel comprising a sample inlet opening and an exhaust opening,

the channel allows for moving a sample liquid containing a solid component from the sample inlet opening toward the exhaust opening and for providing a liquid reaction field;

a first electrode and a second electrode which are used to apply voltage to the liquid reaction field,

wherein a distance from the sample inlet opening to the first electrode is greater than a distance from the sample inlet opening to the second electrode,

wherein the first electrode comprises an electron transfer interface for providing electrons to the liquid reaction field or receiving electrons from the reaction field when voltage is applied to the liquid reaction field via the first and second electrodes;

a concentration means for increasing the concentration of the solid component in a part in which solid component contacts the electron transfer interface in the liquid reaction field; and

a water-absorbing layer positioned only downstream from the second electrode in a flow direction of the sample liquid,

wherein the water-absorbing layer allows flow of the sample liquid from the sample inlet opening toward the second electrode but restricts flow of the sample liquid from the first electrode toward the exhaust opening.

2. The measuring instrument according to claim 1, wherein the water-absorbing layer contains an absorbent polymer material.

3. The measuring instrument according to claim 2, wherein the absorbent polymer material has water absorption power of 10 to 500 g/g.

4. The measuring instrument according to claim 2, further comprising a substrate on which the first and the second electrodes are positioned, and a cover above the substrate.

5. The measuring instrument according to claim 4, wherein the water-absorbing layer is formed as a film on at least that part of the cover which faces the electron transfer interface.

6. The measuring instrument according to claim 5, wherein the water-absorbing layer without water absorption and with water absorption has thicknesses of 1/30 to 1/10 and ⅕

to ⅗

, respectively, relative to a depth of the channel.

7. The measuring instrument according to claim 4, wherein the water-absorbing layer comprises a powder of the absorbent polymer material is supported on the cover.

8. The measuring instrument according to claim 7, wherein the powder has a weight average grain size of 100 to 1000 μ

m without water absorption.

9. The measuring instrument according to claim 2, wherein the water-absorbing layer is provided downstream in a flow direction of the sample liquid from the electron transfer interface in the channel.

10. The measuring instrument according to claim 9, wherein the water-absorbing layer has a relative length in the flow direction of the sample liquid is ¼

to ½

of a distance from the sample inlet opening of the channel to a furthest downstream point of the electron transfer interface in the flow direction of the sample fluid.

11. The measuring instrument according to claim 9, wherein the water-absorbing layer is formed so that a portion of the channel in which the water-absorbing layer with water absorption is spaced from the cover by 0 to 15 μ

m.

12. The measuring instrument according to claim 4, wherein at least a portion of the water-absorbing layer has a part positioned either upstream from or downstream from the electron transfer interface while also being positioned adjacent to the electron transfer interface.

13. The measuring instrument according to claim 12, wherein the water-absorbing layer comprises a part positioned upstream from and adjacent to the electron transfer interface, and another part positioned downstream from and adjacent to the electron transfer interface.

14. The measuring instrument according to claim 13, wherein the water-absorbing layer surrounds the electron transfer layer.

15. The measuring instrument according to claim 1, wherein the sample liquid is blood containing blood cells.

16. A measuring instrument comprising:

a channel for moving a sample liquid containing a solid component and for providing a liquid reaction field, and

first and second electrodes which are used to apply voltage to the liquid reaction field,

wherein the first electrode comprises an electron transfer interface for providing electrons to the liquid reaction field or receiving electrons from the reaction field when voltage is applied to the liquid reaction field via the first and second electrodes, the measuring instrument comprising concentration means for increasing the concentration of the solid component in a part which contacts the electron transfer interface in the liquid reaction field;

wherein the concentration means comprises a water-absorbing layer containing an absorbent polymer material; and

wherein the absorbent polymer material has a water absorption power of 10 to 500 g/g.