Fuji Photo Film Company, Limited

Fuju Photo Film Co., Ltd.

Yoshikazu Amano

Toshihiro Mori

Harumi Katsuyama

Kazuya Kawasaki

Osamu Seshimoto

Hideaki Tanaka

Fuminori Arai

Hiroshi Shinoki

Asaji Kondo

Kiyoshi Yamada

Yoshiki Sakaino

Shigeki Kageyama

Masashi Ogawa

Masao Kitajima

Mitsutoshi Tanaka

Takaki Arai

Yoshihide Iwaki

Masaaki Terashima

Toshihisa Ito

Keiko Kato

Hitomi Ito

The immunoassay element for quantitatively analyzing an antigen by determining the change in enzymatic activity of an enzyme-labelled antigen or antibody caused by an immunological reaction. The immunoassay element comprises a substrate layer containing a non-diffusible substrate which forms a diffusible material in the presence of the labelling enzyme, and a reagent layer containing a fragmenting enzyme for further fragmenting the diffusible material into a lower molecular weight product. As the non-diffusible substrate, a substrate capable of reacting solely with the labelling enzyme and incapable of reacting the fragmenting enzyme is utilized. When an endo-active glucosidase is used as the labelling enzyme, and an exo-active glucosidase is used the fragmenting enzyme in the reagent layer, the non-diffusible substrate of the substrate layer is preferred to be an endo type selectively reactive substrate, which means a substrate having a reactivity specific to endo-active glucosidase. Highly sensitive assay is realized with high accuracy and high reproducibility and good storage stability.

Immunoassay element

This invention relates to a dry analytical element using a water-soluble indicator which improves measuring accuracy, which comprises a water-impermeable support, a water-permeable layer and a spreading layer having a function to spread a liquid uniformly, wherein a water-soluble indicator for colorimetry is incorporated into the s preading layer.

Dry analytical element using water-soluble indicator for colorimetry

A plasma- or serum-collecting device with simple structure and easy to handle is provided. The device comprises a vacuum blood drawing tube accommodating a blood-filtering unit, wherein the vacuum tube contains a space above the blood-filtering unit to preserve blood to be filtered and a partition wall under the blood-filtering unit to keep a backspace at reduced pressure, and the blood-filtering unit contains a communicating needle to break the partition wall at the bottom.

Plasma- or serum-collecting device

An agglutination assay method for quantitatively determination of an analyte in a liquid sample using particles bearing an anti-analyte. A non-fluid substance which retains the particles while suppressing the diffusion of the particles therein is used as a medium which is to be a place where the agglutination of the particles takes place. Upon analysis, a solation agent is added to the non-fluid substance medium to increase the fluidity of the non-fluid substance, thereby the particles bearing the anti-analyte can diffuse in the medium to cause the agglutination with the analyte. Preferably, the solation agent is added to the non-fluid medium together with the sample. The non-fluid substance medium containing the particle-labeled anti-analyte can be stored with a higher stability in the dry state. A dry analysis element for enabling such analysis method is also provided.

Agglutination assay method and element in dry system

A composite ion selective electrode comprising a calcium ion selective electrode member and a hydrogen ion selective electrode member which is characterized in that a calcium ion selective membrane of the calcium ion selective electrode member has a thickness of 5 to 30 &mgr;m, and the hydrogen ion selective membrane of the hydrogen ion selective electrode member contains tri-n-dodecyl-amine and trisethylhexyl trimellitate. Each of the calcium ion selective electrode member and the hydrogen ion selective electrode member can be employed singly.

Ion selective electrode

A plasma-collecting devise comprises a blood-filtering element having a blood-drawing needle and a communicating needle, a vacuum blood-drawing tube, and a contracting and expanding element connecting the blood-filtering unit and the vacuum blood-drawing tube. The device enables blood drawing from blood vessel and blood filtering continuously to obtain plasma.

Plasma collecting device

A plasma- or serum-collecting device with simple structure and easy to handle is provided. The device comprises a vacuum blood-drawing tube accommodating a blood-filtering unit, wherein the vacuum tube contains a space above the blood-filtering unit to preserve blood to be filtered and a partition wall under the blood-filtering unit to keep a backspace at reduced pressure, and the blood-filtering unit contains a communicating needle to break the partition wall at the bottom.

Agglutination assay method and element in a dry system

This invention provides a method for the determination of bicarbonate ion existing in liquid using phosphenolpyruvate carboxylase and malate dehydrogenase as conjugate enzyme wherein thioNAD(P)H is used as substrate of malate dehydrogenase. The use of the thioNAD(P)H enables the measurement with visible light, and enables the simple and accurate determination of bicarbonate ion concentration of biological liquid sample in the clinical test.

Method for quantitatively determining bicarbonate ion in liquid and dry analysis device

An analytical element for quantitative analysis of glucose, cholesterol, or lactic acid in whole blood, composed of a porous layer which has a void volume of 30 to 80% and containing peroxidase, a leuco dye which gives coloring having an absorption peak in the region of 600 to 700 nm, and an oxidase such as glucose oxidase, cholesterol oxidase, or lactate oxidase, respectively. The porous layer can be placed on a transparent support sheet via an adhesive layer in the form of dots or lines, or a hydrophilic adhesive layer.

Analytical element for the analysis of whole blood

This invention provides a reagent composition for the determination of bicarbonate ion capable of measuring in a wide determination range in visible light region which comprises a combined substrate of thioNAD(P)H and NAD(P)H for a coupled enzymes of phosphoenolpyruvate carboxylase and malate dehydrogenase.

Method and dry analytical element for determination of bicarbonate ion

A hemoglobin derivative-containing sample is treated with a treating reagent containing 2-butanol and then immunologically analyzed to determine the quantity of the hemoglobin derivative. By the treatment with 2-butanol, the immunological determination for the hemoglobin derivative, particularly HbA.sub.1c, can be attained with high sensitivity by a simple procedure. Since 2-butanol-containing treating reagent does not affect the enzymatic activity, the homogeneous enzyme immunoassay with high sensitivity is realized.

Method for immunological determination of hemoglobin derivative and

A dry analytical element comprising at least one water-permeable reagent layer and a porous spreading layer laminated in this order on a support, wherein at least one layer which is the water-permeable reagent layer, the porous spreading layer or an optional water-permeable layer contains a water-soluble polybasic amino carboxylic acid which is an ampholyte. By applying an analytical element of the invention, an analyte can be measured at a high sensitivity using a small amount of an enzyme, etc., and shelf file can be extended.

Dry analytical element containing ampholyte

A method for correcting an instrumental error due to wavelength error of a spectroscope of an optical analyzer for measuring an optical density reflected from or transmitted through a dry analysis element. One standard color plate having a standard optical density OD.sub.ST is measured by an optical analyzer to be corrected to obtain an measured value OD.sub.M. A measured optical density OD.sub.S of the element applied with a sample through the optical analyzer to be corrected is corrected by using a ratio of OD.sub.M /OD.sub.ST to obtain a corrected measured value OD.sub.C of the sample. The standard color plate to be used contains an indicator dye contained in the non-reacted dry analysis element or a dye having an absorption spectrum same as or similar to that of the indicator dye in the measurement wavelength range. Another correction method in consideration of a layer coefficient of a dry analysis element is also provided.

Method for correcting instrumental error of spectroscope of optical

A multilayer analytical element for measuring enzyme activity in a liquid sample such as a body fluid which is less affected by intrinsic pyruvic acid contained in the liquid sample is disclosed. The analytical element comprises a support, a reagent layer, an optionally provided other layer, and a porous spreading layer. The reagent layer and/or the optionally provided other layer contain pyruvic acid oxidase. The characteristic feature of the analytical element lies in that the spreading layer has a specific void volume in the range of 3-15 .mu.l/cm.sup.2.

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Saitama, Japan

Yoshikazu Amano