Matsushita Electric Industrial Co., Ltd.

Other

Kyoto Daiichi Kagaku Co., Ltd.

Shiro Nankai

Toshihiko Yoshioka

Shin Ikeda

Motokazu Watanabe

Tomohiro Yamamoto

Takashi Iijima

Mariko Kawaguri

Miwa Hasegawa

Hideyuki Baba

Haruhiro Tsutsumi

Yuko Taniike

Yoshinobu Tokuno

Takahiro Nakaminami

Keiko Yugawa

Kenichi Nakamura

Junko Iwata

Shoji Miyazaki

Yoshiko Miyamoto

Mariko Miyahara

Satoko Fujisawa

Syoji Miyazaki

Shigeki Joko

Yoshinori Toyoguchi

Akihiro Imai

Tooru Matsui

Mariko Miyashita

Takatoshi Uchigaki

Masataro Fukuda

Junichi Yamaura

Hiroshi Hyodo

Seiji Takeshima

Junko Nakayama

Minoru Fukuda

Ken-ichi Nakamura

Keiko Yukawa

Tashi Iijima

Mayumi Ohtani

Masahiro Yoshioka

Naoki Tanimoto

Kyozo Terao

A biosensor comprising: an electrically insulating base plate; an electrode system comprising a working electrode and a counter electrode formed on the base plate; a cover member which is joined to the base plate to form a sample solution supply pathway for supplying a sample solution to the electrode system between the cover member and the base plate; and a reagent system comprising at least an oxidoreductase and an electron mediator disposed in the sample solution supply pathway, wherein the electron mediator is provided on the base plate and the oxidoreductase is provided on the cover member such that the electron mediator and the oxidoreductase are not in contact with each other.

Biosensor

A biosensor that is highly responsive and capable of rapid and highly sensitive quantification of a specific component contained in a sample is provided. The biosensor of this invention comprises: an electrically insulating base plate; an electrode system comprising a working electrode and a counter electrode disposed on the base plate; and a reagent system comprising an oxidoreductase which catalyzes the oxidation reaction of glucose, gluconolactonase and a buffer. The buffer is selected from the group consisting of phthalic acid and its salts, maleic acid and its salts, succinic acid and its salts, phospholic acid and its salts, acetic acid and its salts, boric acid and its salts, citric acid and its salts, glycine, tris(hydroxymethyl)aminomethane, piperazine-N,N'-bis(2-ethane sulfonic acid) and the like.

There is provided a cholesterol sensor with high-accuracy and excellent response, whose object to be measured is whole blood, where plasmawithwhich is obtained by filtering outhemocytestherein filteredin bloodcan rapidly reach an electrode system. In a biosensor where plasmawithwhich is obtained by filtering outhemocytestherein filtered withbya filter is sucked into a sample solution supply pathway due to capillarity, there are formed: a first pressing part for holding a primary side portion of the filter from the bottom; a second pressing part for holding a secondary side portion of the filter from the top and the bottom; a third pressing part for holding the central portion of the filter from the top; and a void for surrounding the filter between the second pressing part and third pressing part.

The present invention provides a biosensor having a favorable response characteristic up to a high concentration range, a low blank response and a high storage stability. This sensor comprises an electrode system including a working electrode and a counter electrode, for forming an electrochemical measurement system by coming in contact with a supplied solution; an electrically insulating supporting member for supporting the electrode system; a first reagent layer formed on the working electrode; and a second reagent layer formed on the counter electrode, wherein the first reagent layer comprises an enzyme as the main component, and the second reagent layer comprises an electron mediator as the main component.

The present invention provides a high-performance glucose sensor having excellent storage stability and an improved response characteristic. This sensor comprises: an electrically insulating base plate; an electrode system including at least a working electrode and a counter electrode formed on the base plate; and a reaction layer containing at least pyrrolo-quinoline quinone dependent glucose dehydrogenase, formed in contact with or in the vicinity of the electrode system, and the reaction layer contains at least one kind of additive selected from the group consisting of gluconic acid and salts thereof.

Glucose sensor

A sensor including an insulating base plate; an electrode system, provided on the base plate, having a measuring electrode and a counter electrode; a reaction layer including at least an oxidoreductase and an electron mediator; a sample solution supply pathway including the electrode system and the reaction layer; and a sample supply unit, wherein the sensor is so structured that, between the sample supply unit and the sample solution supply pathway, there is provided a filter having a function to filter out hemocytes and having a cross-sectional area larger than an opening of the sample solution supply pathway, and that plasma of a blood with hemocytes thereof having been filtered out is sucked into the inside of the sample solution supply pathway owing to capillary phenomena.

A highly sensitive biosensor that uses a smaller amount of sample for measurement is described. The biosensor includes a first insulating base plate having a working electrode, a second insulating base plate having a counter electrode opposed to the working electrode, and a reagent layer containing at least an oxidoreductase. The biosensor further includes a sample supply pathway formed between the first and second insulating base plates, where the working electrode, counter electrode and reagent layer are exposed to an inside of the sample supply pathway, and the distance between the working electrode and the counter electrode is 150 &#x3bc;m or less.

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.

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

A sample solution treating instrument is provided for facilitating rapid and simplified adjustment of the condition of a sample solution proper for analysis with a biosensor before supplying the solution to the biosensor. The sample solution treating instrument includes, for example, a catalyst or an adsorbent which can remove any interfering substance in order to adjust the sample solution for measurement with a biosensor.

Sample treating kit and sample treating method using the same for analysis with a biosensor

Disclosed is a highly responsive biosensor comprising a cholesterol-oxidizing enzyme and cholesterol esterase. The biosensor comprises: an electrically insulating base plate; an electrode system including a working electrode and a counter electrode formed on the base plate; a cover member joined with the base plate to define a sample supply pathway through which a sample solution is introduced from a sample supply port to the electrode system, the sample supply pathway being formed between the cover member and the base plate; and a reagent layer formed in the sample supply pathway, wherein the reagent layer contains a cholesterol-oxidizing enzyme, cholesterol esterase, an electron mediator, and a buffer having a buffering capacity in an acidic pH range.

Biosensor and method of substrate quantification

An apparatus for determining the concentration of a substrate in a sample solution using an electrode system comprising a working electrode, a counter electrode, and a reaction layer which contains at least an oxidoreductase and an electron mediator and is formed on the electrode system to electrochemically measure a reduced amount of the electron mediator resulting from enzyme reaction in the reaction layer, wherein a third electrode is formed as an interfering substance detecting electrode. A current flowing between the counter electrode and the third electrode is measured which is taken as a positive error. Subsequently, voltage application between the counter electrode and the third electrode is released and a voltage for oxidizing the reduced form electron mediator is applied between the working electrode and the counter electrode to measure a current flowing between the two electrodes.

Device and method for determining the concentration of a substrate

The present invention provides a biosensor that enables highly-accurate measurement of a sample solution including a solid component like hemocytes and has a little variation in response. The biosensor includes: an insulating base plate, an electrode system having at least a working electrode and a counter electrode provided on the base plate, a cover member that is combined with the base plate to define a sample solution supply pathway for leading a sample solution from a sample supply unit to the electrode system, a reaction reagent system including at least an oxidation-reduction enzyme and an electron mediator, and a filter disposed between the electrode system and the sample supply unit in the sample solution supply pathway. The biosensor has a space that encircles surface of the filter in an area from one end of the filter close to the sample supply unit to the other end of the filter close to the electrode system. This arrangement effectively prevents the solid component like hemocytes from flowing into the electrode system without being filtered out by the filter.

The present invention provides a high performance glucose sensor which can demonstrate high stability against preservation and produces only a low blank value. The glucose sensor comprises an electrically insulating base plate, an electrode system formed on the base plate, and a reaction layer which is formed in contact with or in the vicinity of the electrode system and contains at least a glucose dehydrogenase whose coenzyme is pyrrolo-quinoline quinone, the reaction layer further containing an additive such as phthalic acid.

The present disclosure relates to a method for determining cholesterol in low density lipoprotein comprising the steps of (a) measuring total cholesterol level in a sample containing at least high density lipoprotein, low density lipoprotein, very low density lipoprotein and chylomicron, and (b) measuring cholesterol levels in the high density lipoprotein, very low density lipoprotein and chylomicron in the sample, wherein the cholesterol level in the low density lipoprotein is determined by subtracting a value obtained in the step (b) from a value obtained in the step (a). The present invention enables concurrent determination of cholesterol level in low density lipoprotein and total cholesterol level, facilitating acquisition of two types of biological information at a time.

Method of determining cholesterol and sensor applicable to the same

A biosensor comprising an electrically insulating base plate, an electrode system containing a working electrode and a counter electrode disposed on the base plate, and a reagent system comprising at least an oxidoreductase, a hydrophilic polymer and an electron mediator, wherein the reagent system further comprises a substance having a function to convert an organic product generated by direct reaction of a substrate to be measured with the oxidoreductase to another compound.

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Hirakata, Japan

Shiro Nankai