Invitrogen™ Thyroxine (T4) Competitive ELISA Kit

ELISA

The Thyroxine (T4) ELISA quantitates Thyroxine (T4) in serum, plasma, urine, dried fecal extracts, or cell culture medium. The assay will exclusively recognize both natural and recombinant Thyroxine (T4). Principle of the method The Thyroxine (T4) solid-phase sandwich ELISA (enzyme-linked immunosorbent assay) is designed to measure the amount of the target bound between a matched antibody pair. A target-specific antibody has been pre-coated in the wells of the supplied microplate. Samples, standards, or controls are then added into these wells and bind to the immobilized (capture) antibody. The sandwich is formed by the addition of the second (detector) antibody, binding to the target on a different epitope from the capture antibody. A conjugated enzyme has been incorporated into the assay. After incubation and washing steps to rid the microplate of unbound substances, a substrate solution is added that reacts with the enzyme-antibody-target complex to produce measurable signal. The intensity of this signal is inversely proportional to the concentration of target present in the original specimen. Rigorous validation Each manufactured lot of this ELISA kit is quality tested for criteria such as sensitivity, specificity, precision, and lot-to-lot consistency. See manual for more information on validation.