Thyroxine ELISA Kit (T4)


Human thyroxine ELISA kit is a reliable quantitative method to a measuring T4 (thyroxine) in human serum or plasma. This assay has a detection limit of 8.0 nmol/l.


Thyroxine (T4) is a hormone that is stored and synthesised in the thyroid gland. The proteolytic cleavage of follicular thyroglobulin results in the releasing T4 into the bloodstream,  over 99% of thyroxine is found to be reversibly bound to at least three different plasma proteins in blood, thyroxine binding globulin (TBG), albumin or thyroxine binding pre-albumin (TBPA). Only a small fraction which represent the active form is found unbound (free) state at any one time.

This assay can be used to detect these excess levels that are circulating freely around the body. The primary function of thyroxine is to increase the body’s sensitivity to catecholamines and to interfere with protein synthesis, this will raise the basal metabolic rate. Hyperthyroidism and thyrotoxicosis are both clinical syndromes which are due to excess levels of circulating; free T4, free T3 or both.


All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

  • Microtiterwells, 12 x 8 (break apart) strips: Wells coated with anti-T4 antibody.
  • Standard 0-5: Concentration 0-250 nmol/l.
  • Control Low and Control High.
  • Enzyme Conjugate: Consisting of antibody conjugated to horseradish peroxidase (HRP).
  • Substrate Solution: Tetramethylbenzidine (TMB).
  • Stop Solution: 0.5 M H2SO4, Avoid contact with the stop solution. It may cause skin irritations and burns.
  • Wash Solution (40x Concentrated).


The minimum detectable sensitivity limit of human thyroxine (T4) using current thyroxine ELISA kit was approximately 8.0 nmol/l. The dynamic range for this assay is determined to be between 25.0 – 250.0 nmol/l.


  1. Determination of Protein Bound Iodine. Joumal Biological Chemistry (1948) 173, 175. Barker, S.B.
  2. A Radioimmunoassay of Thyroxine. J. Clinical (1971) EndocrinoL, 33, 865. Chopra, I.J., Solomon, D.H., and Ho, R.S.
  3. Effects of Drugs on Clinical Laboratory Tests. Clinical Chemistry, (1975) 21, 3660. Young, D.S., Pestaner, L.C., and Gilberman, U.
  4. Diagnosis and Treatment of Thyroid Disease, Cleveland CRC Press (1975) P. 19 51. Sterling, L.


  • Full Name: Thyroxine ELISA Kit (T4)
  • Reactivity: Human
  • Sample Type: Serum
  • Sensitivity:  8.0 nmol/l


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