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: An immunoassay reagent is obtained whereby a microscale substance such as an antigen or antibody can be assayed at a high sensitivity, and whereby a need to separate a reacted substance, e.g., an immunoreacted substance, from an unreacted substance can be eliminated or such a separation can be simplified. An immunoassay reagent, for use in the quantitative determination of a target antigen or antibody present in a sample, containing an insoluble carrier which carries an enzyme and an antibody or antigen corresponding to the antigen or antibody, an enzyme inhibitor for inhibiting the activity of the enzyme and a substrate with which the enzyme reacts.

Abstract: A hematology analyzer includes a first measuring container having a first sensing device, a second measuring container having a second sensing device, a first auxiliary container diluting blood collected by a sampling nozzle and being arranged so as to allow the first diluted blood solution to flow into the first measuring container; a second auxiliary container further diluting the first diluted blood solution collected in the first auxiliary container by the sampling nozzle and being arranged so as to allow the second diluted blood solution to flow into the second measuring container, and first blood cells contained in the first diluted blood solution poured into the first measuring container from the first auxiliary container are measured by the first sensing device, and second blood cells contained in the second diluted blood solution poured into the second measuring container from the second auxiliary container are measured by the second sensing device.