Patent ID: 8043866

Claim:
An immunochromatography method comprising: (i) developing an analyte and a labeling substance which is modified with a first binding substance against the analyte in a mixed state on a porous carrier; (ii) capturing the analyte and the labeling substance at a reaction site on the porous carrier having a second binding substance, wherein the second binding substance is capable of binding the analyte or of binding to the first binding substance and the second binding substance captures a complex formed by the analyte and the labeling substance; (iii) adding a silver-containing compound and a reducing agent for silver ions at the reaction site on the porous carrier and forming particles having an average particle size of 1 μm to 20 μm, wherein a particle core is formed by the complex of the analyte and the labeling substance and the reaction time for sensitization using the silver-containing compound and the reducing agent for silver ions is within 7 minutes; and (iv) detecting the analyte by detecting the particles formed in step (iii).