Electrolysis: processes – compositions used therein – and methods – Electrolytic analysis or testing – Involving enzyme or micro-organism
Reexamination Certificate
2002-09-04
2004-03-02
Tung, T. (Department: 1753)
Electrolysis: processes, compositions used therein, and methods
Electrolytic analysis or testing
Involving enzyme or micro-organism
C204S403010, C204S403090, C204S403100, C204S403110, C204S403140
Reexamination Certificate
active
06699382
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an electrochemical analysis element that facilitates rapid and accurate quantitation of a specific component contained in a biological sample such as blood, sweat or the like, or food sample such as food raw material or food product from food industries.
The biosensor disclosed in the Japanese Laid-Open Patent Publication No Hei 3-202764 is a known example of electrochemical analysis element that facilitates simplified quantitation of a specific component, that is, a substrate contained in a biological or food sample without necessitating dilution and subsequent stirring of a sample solution. The biosensor disclosed in this reference is produced by first forming an electrode system on an insulating base plate using screen printing method or the like and subsequently forming a reaction layer containing an oxidoreductase and an electron acceptor on the formed electrode system.
This biosensor quantitates the substrate concentration in a sample by the following procedure.
First, dropping a sample solution on the reaction layer of the biosensor dissolves the reaction layer in the sample solution, which promotes enzyme reaction between the substrate in the sample solution and the oxidoreductase in the reaction layer. Upon enzyme reaction, the electron acceptor in the reaction layer is reduced. A voltage is applied across the electrodes of the sensor after a predetermined time to electrochemically oxidize the reduced electron acceptor. The substrate concentration in the sample is quantitated based on the oxidation current value across the electrodes.
The prior art electrochemical analysis element can readily determine the substrate concentration in a sample of several &mgr;l or more. However, such element has a drawback that it sometimes meets difficulties in making reliable measurement if the sample is very small in amount under several &mgr;l.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention is therefore to provide an electrochemical analysis element that enables reliable measurement of a trace amount of sample.
The electrochemical analysis element in accordance with the present invention comprises a sensor body having a hollow space which space is open at its both ends, an electrode system having a working electrode and a counter electrode and a reagent segment containing an enzyme, wherein the electrode system and the reagent segment are disposed on an inner wall of the hollow space.
In a preferred mode of the present invention, the working electrode is positioned to oppose to the counter electrode on the inner wall of the hollow space.
In another preferred mode of the present invention, the reagent segment further comprises an electron acceptor.
In still another preferred mode of the present invention, the reagent segment is disposed on the working electrode.
When the sample is whole blood, an arrangement of a filter on at least one open end of the hollow space helps to filter red blood cells during passage of the whole blood through the filter. This eliminates inconveniences due to arrival and interference of red blood cells at the reagent segment.
Closure of both open ends of the hollow space with a resin film or aluminum laminate film can enhance reliable preservation of the reagents in the reagent segment.
According to the present invention, a provision of a reagent segment containing glucose oxidase yields an electrochemical analysis element that can quantitate glucose in body fluids. A provision of a reagent segment containing cholesterol oxidase in combination with cholesterol esterase yields another electrochemical analysis element that can quantitate cholesterol in body fluids.
While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and content, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.
REFERENCES:
patent: 3151052 (1964-09-01), Arthur et al.
patent: 3424664 (1969-01-01), Severing Haus
patent: 3556950 (1971-01-01), Dahms
patent: 4533457 (1985-08-01), Watanabe
patent: 4844787 (1989-07-01), Akao et al.
patent: 4966671 (1990-10-01), Nylander et al.
patent: 5130009 (1992-07-01), Marsoner et al.
patent: 5141868 (1992-08-01), Shanks et al.
patent: 5228972 (1993-07-01), Osaka et al.
patent: 5385846 (1995-01-01), Kuhn et al.
patent: 5395503 (1995-03-01), Parce et al.
patent: 5437999 (1995-08-01), Diebold et al.
patent: 5705045 (1998-01-01), Park et al.
patent: 5723345 (1998-03-01), Yamauchi et al.
patent: 195 46 535 (1997-06-01), None
patent: 0 226 470 (1987-06-01), None
patent: 0 351 891 (1990-01-01), None
patent: 0 590 661 (1994-04-01), None
patent: 0 730 037 (1996-09-01), None
patent: 0 795 601 (1997-09-01), None
patent: 0 811 838 (1997-12-01), None
patent: 0 872 728 (1998-10-01), None
patent: 2 254 436 (1992-10-01), None
patent: 60244853 (1985-12-01), None
patent: 61002060 (1986-01-01), None
patent: 03202764 (1991-09-01), None
patent: 04-194660 (1992-07-01), None
patent: 09-084781 (1997-03-01), None
patent: WO 95/10223 (1995-04-01), None
Ikeda Shin
Nankai Shiro
Watanabe Motokazu
Yoshioka Toshihiko
Akin Gump Strauss Hauer & Feld & LLP
Matsushita Electric - Industrial Co., Ltd.
Tung T.
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