Abstract: A biosensor includes a base substrate; an electrode layer disposed on a main surface of the base substrate and including first and second electrode pairs, each pair including a working electrode and a counter electrode; a spacer substrate on the electrode layer and having first and openings, the first opening exposing a part of the first electrode pair and the second opening exposing a part of the second electrode pair; a first reagent layer containing a first reagent reactive with a sample and disposed in the first opening; a second reagent layer containing a second reagent reactive with the sample and disposed in the second opening; and a top cover substrate on the spacer substrate, the top cover substrate including an introduction portion having at least one introduction opening, the introduction portion overlapping a part of the first opening in the spacer substrate and a part of the second opening.

Abstract: A method capable of stirring a liquid sample and a reagent promptly and easily includes the following steps (A) and (B). In step (A), using a cell including: a liquid sample retaining section having a plurality of particles; and a liquid sample supply inlet, a liquid sample containing an analyte is supplied from the liquid sample supply inlet to the liquid sample retaining section. In step (B), the liquid sample and a specific binding substance capable of specifically binding to the analyte are stirred by the movement of the particles caused by the flow of the liquid sample in the cell resulting from the supply of the liquid sample, to obtain a liquid mixture. The electric charge of at least the surface of the particles and the electric charge of the specific binding substance have the same polarity in the liquid mixture.

Abstract: A method capable of stirring a liquid sample and a reagent promptly and easily includes the following steps (A) and (B). In step (A), using a cell including: a liquid sample retaining section having a plurality of particles; and a liquid sample supply inlet, a liquid sample containing an analyte is supplied from the liquid sample supply inlet to the liquid sample retaining section. In step (B), the liquid sample and a specific binding substance capable of specifically binding to the analyte are stirred by the movement of the particles caused by the flow of the liquid sample in the cell resulting from the supply of the liquid sample, to obtain a liquid mixture. The electric charge of at least the surface of the particles and the electric charge of the specific binding substance have the same polarity in the liquid mixture.

Abstract: The present invention provides a dye-labeled protein conjugate in which a protein conjugate is labeled with a large number of dye molecules. In the dye-labeled protein conjugate, a protein conjugate that includes a protein and an antibody bound thereto via a disulfide bond is labeled with a cyanine dye represented by the formula (1) or the formula (2) given below: where R1 and R2 denote hydrogen or an alkyl group, X denotes a halogen, M denotes hydrogen or an alkali metal, and n represents an integer in a range of 1 to 4.

Abstract: A high-sensitive indirect polymerized and labelled antibody is disclosed. The antibody facilitates detection of a low concentration of antigen as an analyte in a sample solution. The indirect polymerized and labelled antibody of the present invention is prepared by polymerizing an antibody using a multi-functional reagent, binding the polymerized antibody with a protein via a disulfide bond of the antibody to form a polymerized antibody conjugate, and labelling the conjugate with a cyanine dye represented by the following formula: where R1 and R2 represent hydrogen or an alkyl group, X represents a halogen, M represents hydrogen or an alkali metal, and n represents an integer of 1 to 4.

Abstract: The present invention provides a highly sensitive dye-labeled and polymerized antibody that can detect a target substance even when the target substance has a low concentration. The dye-labeled and polymerized antibody of the present invention comprises a polymerized antibody, which has been polymerized with a polyfunctional reagent, and a cyanine dye for labeling the polymerized antibody represented by the formula (1) or the formula (2) given below: where R1 and R2 denote hydrogen or an alkyl group, X denotes a halogen, M denotes hydrogen or an alkali metal, and n represents an integer in a range of 1 to 4.

Abstract: The present invention provides a highly sensitive dye-labeled and polymerized antibody that can detect a target substance even when the target substance has a low concentration. The dye-labeled and polymerized antibody of the present invention comprises a polymerized antibody, which has been polymerized with a polyfunctional reagent, and a cyanine dye for labeling the polymerized antibody represented by the formula (1) given below: where R1 and R2 denote hydrogen or an alkyl group, X denotes a halogen, M denotes hydrogen or an alkali metal, and n represents an integer in a range of 1 to 4.

Abstract: The present invention provides a dye-labeled protein conjugate in which a protein conjugate is labeled with a large number of dye molecules. In the dye-labeled protein conjugate, a protein conjugate that includes a protein and an antibody bound thereto via a disulfide bond is labeled with a cyanine dye represented by the formula (1) given below. where R1 and R2 denote hydrogen or an alkyl group, X denotes a halogen, M denotes hydrogen or an alkali metal, and n represents an integer in a rage of 1 to 4.

Abstract: An immunochromatography-assisted device is disclosed which facilitates accurate and rapid detection of an antigen contained in a fluid sample and from which background coloring and blank coloring possibly causing a malfunction at detection are successfully eliminated. The immunochromatography-assisted device comprises a porous carrier having an additive-impregnated part between a sample introducing part and a determining part, the additive-impregnated part carrying at least one selected from the group consisting of a surfactant, a water-soluble ammonium salt and a pH buffer such that it dissolves in a sample introduced into the carrier in order to move with the movement of the sample through the carrier. The porous carrier also has a labelled part segmented into plural zones.

Abstract: The invention relates to a dye-labeled antibody conjugate comprising an antibody conjugate and a cyanine dye. The dye-labeled antibody conjugate is prepared by polymerizing an antibody such as mouse IgG in phosphate buffer using a polyfunctional reagent such as dithiobis(sulfosuccinimidylpropionate), and stirring the antibody and a cyanine dye represented by Formula I . The dye-labeled antibody conjugate is more sensitive to antigens than conventional dye-labeled antibodies because it has many reactive sites to antigens.