METHOD OF ASSAYING ANTIGEN AND REAGENT THEREFOR

摘要

A latex aggregation method whereby the assay scope can be enlarged and the assay sensitivity in a low concentration region can be elevated. A method of assaying a test antigen by the latex aggregation method with the use of sensitized latex particles which comprises: using two groups of latex particles differing in the average particle size (i.e., large and small particles); sensitizing individual latex particles with an antibody capable of undergoing an antigen-antibody reaction with the test antigen; the purity of the antibody to be sensitized on individual latex particles being within a specific range; the ratio of the amount of the antibody to be sensitized per small latex particle to the amount of the antibody to be sensitized per large latex particle, the average particle size of the large latex particles, the average particle size of the small latex particles, the concentration of the large sensitized latex particles in the antigen-antibody reaction system, and the concentration of the small sensitized latex particles in the reaction system each being within a specific range; reacting the large sensitized latex particles and the small sensitized latex particles, which are suspended in a buffer solution, with the test antigen; and then optically measuring the aggregation of the sensitized latex particles.