Directional coupling method of microspheres and antibody, and application

The invention discloses a directional coupling method of microspheres and an antibody. Directional coupling between carboxyl microspheres and an antibody F(ab') is realized in a sulfydryl coupling mode, and an anti-body and microsphere compound is formed. According to the directional coupling method disclosed by the invention, the direction during connecting of the antibody and the microspheres can be effectively controlled, and the directional coupling can be realized, so that the sensitivity of a PETIA (Particle-enhanced Turbidimetric Immunoassay) reagent can be increased, and interference resistance of a reagent on RF (Rheumatoid Factors) can be increased.