Electrochemical biosensor

• US 20040026266A1
• Filed: 06/09/2003
• Published: 02/12/2004
• Est. Priority Date: 06/10/2002
• Status: Active Grant

• Current Assignee: Unilever Home & Personal Care USA (Unilever PLC)
• Original Assignee: Unilever Home & Personal Care USA (Unilever PLC)
• Inventors: Porter, Robert Andrew, Birch, Brian Jeffrey, Atkinson, Anne Louise
• Granted Patent: US 7,198,708 B2
• Time in Patent Office: Days
• US Class Current: 205/778
• CPC Class Codes: C12Q 1/004 mediator-assisted

Abstract

An electrochemical biosensor for quantifying one or more redox species in a liquid sample comprising a background electrochemical activity, wherein said biosensor comprises:

(i) an electrode system;

(ii) a filter means comprising a sample loading position; and

(iii) a charge transfer surface between said filter means and said electrode system;

wherein said filter means separates said sample loading position from said charge transfer surface by an amount of filter material capable of providing a tangential peak height for said background electrochemical activity of less than 30% of the tangential peak height for said redox species; and

said biosensor comprises an intermediate layer between said filter means and said charge transfer surface, wherein said intermediate layer has a lower energy requirement to transfer said liquid sample to said charge transfer surface than said filter material.

Claims

1. An electrochemical biosensor for quantifying one or more redox species in a liquid sample comprising a background electrochemical activity, wherein said biosensor comprises:

(i) an electrode system;

(ii) a filter means comprising a sample loading position; and

(iii) a charge transfer surface between said filter means and said electrode system;

wherein said filter means separates said sample loading position from said charge transfer surface by an amount of filter material capable of providing a tangential peak height for said background electrochemical activity of less than 30% of the tangential peak height for said redox species; and

said biosensor further comprises an intermediate layer between said filter means and said charge transfer surface, wherein said intermediate layer has a lower energy requirement to transfer said liquid sample to said charge transfer surface than said filter material.

2. The electrochemical biosensor of claim 1, wherein said filter material is selected from the group comprising synthetic membranes, nitrocellulose, cellulose, silica, filter paper and agar gel.

3. The electrochemical biosensor of claim 2, wherein said intermediate layer comprises cellulose.

4. The electrochemical biosensor of claim 1, wherein said biosensor comprises a means for measuring an electrochemical signal.

5. The electrochemical biosensor of claim 1, comprising a means for directing the usage of said biosensor within one or more predetermined parameters for quantification of said one or more redox species.

6. A method of using an electrochemical biosensor for quantifying one or more redox species in a liquid sample comprising a background electrochemical activity, said method comprising the steps of

(a) providing an electrochemical biosensor which comprises:

—

(i) an electrode system;

(ii) a filter means comprising a sample loading position; and

(iii) a charge transfer surface between said filter means and said electrode system;

wherein said filter means separates said sample loading position from said charge transfer surface by an amount of filter material capable of providing a tangential peak height for said background electrochemical activity of less than 30% of the tangential peak height for said redox species; and

said biosensor further comprises an intermediate layer between said filter means and said charge transfer surface, wherein said intermediate layer has a lower energy requirement to transfer said liquid sample to said charge transfer surface than said filter material;

(b) contacting the sample loading position with said liquid sample; and

(c) detecting a voltametric change in said electrode system to quantify said redox species.

7. The method of claim 6, wherein said redox species is either ascorbate or reduced glutathione.