Abstract: A problem of the present invention is to provide a method capable of avoiding nonspecific reactions which result in the absence of agglutination that should occur in agglutination inhibition LTIA. The present invention provides a method of avoiding nonspecific reactions in a latex agglutination inhibition test by performing a latex agglutination inhibition assay in the presence of one or more compounds selected from the group consisting of polyoxyethylene-polyoxypropylene block copolymers, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, and polyvalent quaternary amine polymer compounds.

Abstract: A problem of the present invention is to provide a method capable of avoiding nonspecific reactions which result in the absence of agglutination that should occur in agglutination inhibition LTIA. The present invention provides a method of avoiding nonspecific reactions in a latex agglutination inhibition test by performing a latex agglutination inhibition assay in the presence of one or more compounds selected from the group consisting of polyoxyethylene-polyoxypropylene block copolymers, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, and polyvalent quaternary amine polymer compounds.

Abstract: To provide a reagent for assaying anti-Treponema pallidum antibody which reagent contains a polypeptide antigen and which reagent provides high assay sensitivity and high specificity, and to provide an assay method employing the assay reagent. The reagent for assaying anti-Treponema pallidum antibody, for use in an assay of anti-Treponema pallidum antibody on the basis of antigen-antibody reaction is characterized in that the reagent contains, as an antigen, a recombinant polypeptide containing at least domain C and domain D of Treponema pallidum 47 kDa antigen but containing no domain A1 of the 47 kDa antigen.

Abstract: To provide a reagent for assaying anti-Treponema pallidum antibody which reagent contains a polypeptide antigen and which reagent provides high assay sensitivity and high specificity, and to provide an assay method employing the assay reagent. The reagent for assaying anti-Treponema pallidum antibody, for use in an assay of anti-Treponema pallidum antibody on the basis of antigen-antibody reaction is characterized in that the reagent contains, as an antigen, a recombinant polypeptide containing at least domain C and domain D of Treponema pallidum 47 kDa antigen but containing no domain A1 of the 47 kDa antigen.

Abstract: An object of the present invention is to provide: a purified serum albumin having less lot-to-lot variation; and an immunoassay method utilizing the purified serum albumin, in which high reactivity and less non-specific reactions are achieved. The present invention provides a purified serum albumin, which is a serum albumin used as a blocking agent and/or in a suspension containing an insoluble carrier in an immunoassay method, and is composed mostly of a fraction, the fraction having an absorbance of not exceeding 9.0 mAbs when measured in the form of 1% aqueous solution at a wavelength of 463 nm by using a quarts cell having an optical path length of 1.0 cm.

Abstract: An object of the present invention is to provide: a purified serum albumin having less lot-to-lot variation; and an immunoassay method utilizing the purified serum albumin, in which high reactivity and less non-specific reactions are achieved. The present invention provides a purified serum albumin, which is a serum albumin used as a blocking agent and/or in a suspension containing an insoluble carrier in an immunoassay method, and is composed mostly of a fraction, the fraction having an absorbance of not exceeding 9.0 mAbs when measured in the form of 1% aqueous solution at a wavelength of 463 nm by using a quarts cell having an optical path length of 1.0 cm.

Abstract: The present invention provides a novel immunoassay method with high reaction specificity and high sensitivity. The present invention also provides a method for immunoassaying a target antigen utilizing reactivation of an apoenzyme, which includes simultaneously or sequentially adding a test sample to an antibody specific to the target antigen, the target antigen labeled with a coenzyme, an apo-D-amino acid oxidase, a D-amino acid, and a reagent for detecting a hydrogen peroxide produced by the oxidase.

Abstract: The present invention provides a novel immunoassay method with high reaction specificity and high sensitivity. The present invention also provides a method for immunoassaying a target antigen utilizing reactivation of an apoenzyme, which includes simultaneously or sequentially adding a test sample to an antibody specific to the target antigen, the target antigen labeled with a coenzyme, an apo-D-amino acid oxidase, a D-amino acid, and a reagent for detecting a hydrogen peroxide produced by the oxidase.

Abstract: A method of immunologically examining a specimen which comprises attaching a cap having a filter impregnated with a labeled antibody enclosed therein to a container body containing a diluted liquid specimen, pouring the diluted liquid specimen from the container into a test device, observing the reaction and thus examining the presence or absence of an analyte in the specimen. This examination method, whereby effects of differences among individual operators can be minimized and the occurrence of a nonspecific reaction can be prevented, is highly excellent in the reproducibility of the examination results and storage stability of a test reagent. A specimen container to be used in the above method to which a cap having a filter impregnated with a labeled antibody enclosed therein is attached. This container is appropriately usable as a member constituting a simplified diagnosis kit.

Abstract: A method for accurately determining the particle diameter of gold colloid in a simple manner, and a gold colloid solution with a particle diameter within a desired range are described. A method for estimating the particle diameter distribution width of gold colloid based on the measurement of, in addition to the maximum absorption wavelength, a ratio (A?X/A?max) of the absorbance (A?X) at a wavelength differing from the maximum absorption wavelength to the absorbance (A?max) at the maximum absorption wavelength of the gold colloid solution, and the gold colloid solution obtained by the method are provided.

Abstract: A method of immunologically examining a specimen which comprises attaching a cap having a filter impregnated with a labeled antibody enclosed therein to a container body containing a diluted liquid specimen, pouring the diluted liquid specimen from the container into a test device, observing the reaction and thus examining the presence or absence of an analyte in the specimen. This examination method, whereby effects of differences among individual operators can be minimized and the occurrence of a nonspecific reaction can be prevented, is highly excellent in the reproducibility of the examination results and storage stability of a test reagent. A specimen container to be used in the above method to which a cap having a filter impregnated with a labeled antibody enclosed therein is attached. This container is appropriately usable as a member constituting a simplified diagnosis kit.

Abstract: A method for quantitatively measuring analyte in an undiluted whole blood sample is disclosed which involves contacting an undiluted whole blood sample comprising the analyte with magnetically-responsive particles which comprise a first partner which is coated on a magnetically-responsive particulate insoluble carrier, wherein the first partner specifically binds to the analyte to form a first complex of insoluble carrier-first partner-analyte, separating the resulting first complex from the undiluted whole blood sample, thereafter contacting the resulting separated first complex with a second partner which is labelled with a detectable marker and which specifically binds to the analyte to form a second complex of insoluble carrier-first partner-analyte-second partner, and separating the resulting second complex from unbound second partner by washing, and thereafter detecting the marker in the second complex to quantitatively measure the analyte in the undiluted whole blood sample, and wherein the initial con