Thyroxin (T4) ELISA kits are assays designed to detect the hormone thyroxine, also called T4. Produced by the thyroid gland along with triiodothyronine (T3), it is responsible for the regulation of growth and metabolism in the body. It contains iodine and can therefore be used as an indicator of iodine deficiency. T4 acts as a prohormone and can be converted to T3. Levels of free T4 in blood can be measured to evaluate thyroid gland function and monitor efficacy of treatment in thyroid disorders. Visit the supplier page for more information about detection range and reactivity.