PREPARATION AND USE OF REAGENT CONTAINING COLLOIDAL PARTICLE HAVING SELECTED PARTICLE SIZE AND NARROW IN DISTRIBUTION

摘要

PURPOSE: To obtain a reagent containing metallic sol particles having a selected narrow particle size distribution by generating cores by reducing a metal-containing solution under the presence of a stabilizer and generating the metallic sol particles while the natural generation of cores is inhibited with a second reducing agent. CONSTITUTION: Cores or seed crystals are generated by adding a strong reducing agent, such as hydrogen peroxide, etc., to a metallic salt solution under the presence of a stabilizer, such as a citrate, etc. Then metallic sol particles having a selected particle size are generated by inhibiting the natural generation of cores by adding a metallic salt solution containing a second reducing agent, such as hydroxylamine, etc., to the generated cores. Thereafter, the particles are coated with a material containing a protein, such as the antigen, antibody, etc., after the second reducing agent is inactivated by adjusting the pH, or combining the pH with bovine serum albumin, or using a chemical agent and post-coated with dry fat milk after the particles are pre-treated with a reducing agent and capped with a sulfhydryl blocking agent. Therefore, a reagent which contains metallic sol particles having a selected narrow particle size distribution and can be used as an immunoassay reagent or cell marker or labeling for microscopic inspections can be obtained.