Detection Method:Competitive ELISA
Test principle:This assay employs the competitive enzyme immunoassay technique. The microtiter plate provided in this kit has been pre-coated with an antibody specific to TAb. Standards or samples are then added to the appropriate microtiter plate wells with a Horseradish Peroxidase (HRP)-conjugated TAb and incubated. The competitive inhibition reaction is launched between with HRP labeled TAb and unlabeled TAb with the antibody. A substrate solution is added to the wells and the color develops in opposite to the amount of TAb in the sample. The color development is stopped and the intensity of the color is measured.
Product Overview:T4, the principal thyroid hormone largely bound to transport proteins, especially TBG. Given normal levels of thyroid hormone-binding proteins, hyperthyroidism is characterized by increased levels of circulating T4, hypothyroidism by decreased levels. Exceptions to this parallelism between thyroid status and total T4 concentration are found. Levels of TBG are known to be altered under various physiological, pharmacological and genetic conditions. Elevated T4 levels may be obtained when TBG levels are high, as in pregnancy, acute intermittent? porphyria, hyperproteinemia, hereditary TBG elevation and in patients undergoing estrogen therapy or taking oral contraceptives. Total T4 levels may be depressed when TBG levels are low, as in nephrotic, hepatic, gastrointestinal and neoplastic disorders; in acromegaly, hypoproteinemia and hereditary TBG deficiency; and in patients undergoing androgen, testosterone or anabolic steroid therapy.
