Abstract: A problem to be solved by the invention is to improve the sensitivity of measurement of an analyte in a sample by a sandwich immunoassay. The sensitivity can be improved significantly in a sandwich immunoassay using a first antibody and a second antibody when one or both of the first antibody and the second antibody are a mixture of a monoclonal antibody recognizing a linear epitope and a monoclonal antibody recognizing a conformational epitope.

Abstract: What is required is a method of producing, without treating a glycoprotein in a biological sample with a denaturing agent in advance, a selectively binding material, which specifically reacts with a glycan of a glycoprotein, a selectively binding material such as antibody thus produced by the method, and a method of specifically detecting a glycoprotein by using the selectively binding material. In order to solve the problems, the present invention produces a selectively binding material specifically reactive with a glycan of a glycoprotein by treating the glycoprotein with a glycan-specific glycan-cleaving enzyme.

Abstract: The present invention is intended to enable detection of specific human BNP fragments solely by immunoassay, and, through a ratio measurement of the human BNP fragments, provides a convenient way of providing information useful for diagnosis and prognosis of heart disease. The invention achieves this by providing an assay that uses an antibody specific to human BNP fragment (4-32)—a fragment that has not caught much attention in the past. Provided herein is an immunoassay method for human BNP fragment (4-32) in a sample, and the method uses an antibody that reacts with human BNP fragment (4-32) but does not react with full-length human BNP (1-32), human BNP fragment (3-32), and human BNP fragment (5-32). Also provided herein is an assay in which the antibody is an antibody that reacts with human BNP fragment (4-32) at a site containing the N-terminus, and that reacts with human BNP fragment (4-10).

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventors reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventors surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: Provided is a method for the simple and highly accurate assay of PSA by a one-step reaction that does not use carriers having different average grain sizes. Also provided is a reagent therefor. The PSA assay method comprises sensitizing insoluble carriers having the same average grain size within a range of greater than 0.20 ?m but 0.40 ?m or less using two types of anti-PSA monoclonal antibodies having different epitopes that are anti-PSA monoclonal antibodies that will react with both free PSA and PSA-ACT, which is a complex of free PSA and ?1-antichymotrypsin, and bringing the carriers into contact with a sample in the presence of an aggregation promoter.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: An objective of the present invention is to provide an anti-human IgM monoclonal antibody that is capable of reacting specifically with human IgM and inducing immunoagglutination based on an antigen-antibody reaction with human IgM in solution, and an immunoassay using the said monoclonal antibody. Another objective of the present invention is to provide an agent for suppressing non-specific reactions caused by human IgM that could not be prevented by conventional methods, and an immunoassay in which non-specific reactions caused by human IgM are suppressed. By selecting a monoclonal antibody that reacts with human IgM on the basis of evaluation of reactivity with human IgM in solution, a novel monoclonal antibody capable of agglutinating human IgM by itself and performing a practical immunoagglutination assay has been obtained, and the objectives above have been thus achieved.

Abstract: The present invention provides an insulin-specific assay and an assay reagent capable of sensitively and specifically assaying insulin using an antibody having a property of reacting with insulin bound to an anti-insulin antibody while not reacting with insulin not bound to an anti-insulin antibody, without being affected by proinsulin and insulin analogs.

Abstract: Provided is a method for the simple and highly accurate assay of PSA by a one-step reaction that does not use carriers having different average grain sizes. Also provided is a reagent therefor. The PSA assay method comprises sensitizing insoluble carriers having the same average grain size within a range of greater than 0.20 nm but 0.40 nm or less using two types of anti-PSA monoclonal antibodies having different epitopes that are anti-PSA monoclonal antibodies that will react with both free PSA and PSA-ACT, which is a complex of free PSA and ?1-antichymotrypsin, and bringing the carriers into contact with a sample in the presence of an aggregation promoter.

Abstract: To adjust detection sensitivity and expand a measurement range depending on objects to be detected by a simple procedure in an immunoassay method involving using a colloidal metal having immobilized thereon an antibody or an antigen. Blocking treatment for a surface of a colloidal metal particle having immobilized thereon an antibody or an antigen with both components, i.e., a component of biological origin and a component of non-biological origin enables adjustment of measurement sensitivity with, for example, kinds and concentrations of both the components, and enables use of the component of non-biological origin, which has not been usable alone because of aggregation of a colloidal metal.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.

Abstract: A problem to be solved by the present invention is to provide an immunochromatographic test strip and a detection method using immunochromatography avoiding aggregation of colloidal gold conjugates while red blood cells in whole blood are agglutinated and then separated and removed in the case of using polybrene as a blood-agglutinating agent and the colloidal gold conjugates as a detection reagent. To solve the problem, the present inventers reviewed a past reagent configuration itself from a completely different viewpoint rather than selecting type and amount of polyanions and, as a result of extensive study on each element, the inventers surprisingly found that aggregation of colloidal gold can be suppressed by using a certain buffer solution without using neutralization by polyanions.