Immunoaffinity purification of human alpha-fetoprotein (AFP) using monoclonal antibodies.

A two-step immunoaffinity isolation procedure for human alpha-fetoprotein (AFP) was developed resulting in highly purified AFP at high yield. A monoclonal antibody immunoadsorbent was used in the first step. Elution of AFP was carried out at alkaline pH by a solution of 0.5 mol/l ammonia containing 0.5 mol/l sodium chloride. To remove impurities caused by the first step, an anti-mouse immunoglobulin antibody immunoadsorbent was applied in the second step.