SYNTHESIS OF AN IMMUNOGEN AND A NOVEL RADIOTRACER OF ESTRADIOL

The preparation and characterization of an immunogen of estradiol is d escribed. The 17-monosuccinate of estradiol (E-17MS) was coupled to bo vine serum albumin (BSA) using carbodiimide. The immunogen was charact erized for its chemical structure by various analytical methods. Rabbi ts were immunized, and the antisera collected was checked for immunore activity. A novel radiotracer was prepared by conjugation of E-17MS to tyrosine methyl ester hydrochloride (TME) using carbodiimide and radi olabeled by sodiumiodide(125). Incubation of raw antiserum was carried out in the presence of E-17MS-(TMEI)-I-125. Separation of free tracer from the bound form was achieved by a dextran-coated charcoal suspens ion. The percentage binding obtained was around 34%, thereby confirmin g the immunogenic potential of the antigen prepared.