Development and Characterization of anti-Estradiol Polyclonal Antibody

This paper reports an indirect competitive enzyme-linked immunosorbent assay (icELISA) using polyclonal antibody (pAb) for estradiol (E-2) residues. After derivation, E-2 haptens were conjugated to bovine serum albumin (BSA) and ovalbumin (OVA) through 1-Ethyl-3-(3-dimethylaminopropy) carbodiimide (EDC) method, and New Zealand white rabbits were immunized to produce anti-E-2 pAb. The conjugation ratio of E-2-BSA was proved to be 18.6:1 by an UV absorbance method. Based on the square matrix titration, an icELISA standard curve was developed. The dynamic range was from 0.16 to 128 ng/mL, with LOD and IC50 value of 0.08 ng/mL and 3.76 ng/mL, respectively. Except for a little cross-reactivity (16.2%) to estrone, this assay showed negligible cross-reactivity to other analogues tested. The results suggest that the produced anti-E-2 pAb could be used to develop an icELISA method for the determination of E-2 residues in animal-originally products.