Specificity of Antiserum raised against Estetrol using 6-O-Carboxymethyloxime-Bovine Serum Albumin Conjugate

In order to obtain the specific antiserum used for radioimmunoassay of estetrol a new hapten-carrier conjugate was prepared from 6-ketoestetrol O-carboxymethyloxime by coupling with bovine serum albumin employing the mixed anhydride technique. The specificity of anti-estetrol antiserum elicited in the rabbit by immunization with this antigen was tested by cross-reaction studies with the closely related steroids. The results indicated that highly specific antiserum to estetrol would be produced by antigen whose steroidal moiety is coupled to a protein through the position remote from the inherent functional groups.