Estradiol (E2)-3-HRP Antigen

A ready-to-use liquid conjugate from Antibodies.com, this C3-linked estradiol-HRP reagent is prepared by coupling 17β-estradiol through the C3 hydroxyl position to horseradish peroxidase, preserving the D-ring epitope recognized by most anti-estradiol antibody specificities. Supplied as 1 ml of working solution, the antigen-HRP conjugate functions as the labeled analog in competitive immunoassay workflows, where it competes with free estradiol in test samples for binding sites on anti-estradiol capture antibodies. Because the steroid is tethered at C3 rather than at the functional C17 hydroxyl, polyclonal and monoclonal antibodies raised against the C17-conjugated immunogen retain strong recognition of the free hormone, making this tracer a practical choice for competitive assay plate-coating protocols. The HRP label enables chromogenic readout with TMB or other peroxidase substrates, and the liquid format removes the need for on-board reconstitution during plate setup. Reproductive endocrinology, estrogen metabolism, and veterinary hormone cycle researchers deploy this reagent in direct competition assays for quantifying estradiol. The product is classified research use only and should be handled with cold-chain precautions to preserve enzymatic activity of the peroxidase moiety over its working shelf life.