T4/Thyroxine ELISA Kit

From Assay Genie, this competitive ELISA kit is specifically designed for the quantitative measurement of thyroxine (T4) levels in human serum, plasma, and cell culture supernatants, with reactivity listed as universal. The format is competitive ELISA with the plate coated with antigen, and detection is performed colorimetrically.

Validated sample types include serum, plasma, cell culture supernatant, cell or tissue lysate, and other liquid samples. Reported sensitivity is 0.422 ng/mL with a detection range of 0.703–45 ng/mL. Linear dilution behaviour has been demonstrated at 1:2, 1:4, and 1:8 in serum (86–103%), EDTA plasma (82–99%) and heparin plasma (80–98%). Recovery ranges in serum (85–103%, average 94%), EDTA plasma (89–103%, average 98%) and heparin plasma (87–103%, average 96%) are provided. Storage is at 2–8°C in a sealed state; components should not be cryopreserved.

The procedure involves adding standards or samples together with biotin-labelled antibody to the plate, incubating at 37°C, washing, developing with TMB substrate in the dark at 37°C, stopping the reaction, and reading absorbance at 450 nm.