Synthesis of new steroid haptens for radioimmunossay. Part IV. 3-O-Carboxymethyl ether derivatives of estrogens. Specific antisera for radioimmunossay of estrone, estradiol-17beta, and estriol.

The syntheses of 3-O-carboxymethyl ether derivatives of estrone, estradiol-17beta, and estriol and the preparation of their bovine serum albumin (BSA) conjugates are described. These conjugates were employed for the generation of specific antisera suitable for radioimmunoassay (RIA) of estrone, estradiol-17beta, and estriol. The previous concept that specific antisera for estrogens cannot be obtained by employing estrogens derivatized at the 3-position is unfounded.