Thyroxine ELISA Kit


Human thyroxine ELISA kit is a reliable quantitative method to a measuring human 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 human T4 ELISA kit can be used to detect these excess levels that are circulating freely around the body. The main function is to act on the body in order to increase the basal metabolic rate by increasing sensitivity to catecholamines (e.g. adrenaline) and by affecting protein synthesis. Hyperthyroidism and thyrotoxicosis are both clinical syndromes which are due to excess levels of circulating free T4, free T3 or in some cases both. Also, there are many publication which indicate that both triiodothyronine (T3) and thyroxine (t4) are known to be useful in treating hypothyroidism (thyroid hormone deficiency).


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. Made up from thyroxine.
  • Control Low and Control High. Containing human T4.
  • Enzyme Conjugate: Consisting of anti-T4 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 human T4 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
  • Reactivity: Human
  • Sample Type: Serum
  • Sensitivity:  8.0 nmol/l



Your secretory IgA ELISA gave good results and I was also really impressed with how quickly we received it.

L. Johnston
PhD Student / University of Glasgow

It is refreshing to know that you have a technical team that is very knowledgeable. I have already recommended your company to other researchers in our department.

Dr. P. Anderson
Lecturer / University College London (UCL)

I am a first time user and found that your instruction manual was very easy to follow. The insulin ELISA assay performed well and I was happy with the results that were generated.

J. Thomas
Senior Technician / Addenbrooke’s Hospital

I carried out a pilot study comparing the performance of many ELISA assay's from different suppliers and found your kits to be one of the better performers. We observed good linearity and tight replicates.

Dr. C. Davies
Lead Scientists / AstraZeneca

You are my first point of contact when I am looking to purchase ELISA. You have such an easy and simple system, yet it is very effective.

A. Shaw
Purchasing / University of Oxford