Free Triiodothyronine (FT3) ELISA Kit

  • Created on the 2 February, 2017.


Free triiodothyronine ELISA kit is a reliable quantitative procedure to measure free triiodothyronine (FT3, Free T3) levels in human serum. The detection sensitivity limit of this assay is 0.05 pg/mL.


The biologically active form of triiodothyronine (free T3) is only represented by a small fraction (approx. 0.3%). This is the circulating hormone that is unbound (free) from any carrier proteins such as thyroxine-binding globulin (TBG). In many clinical conditions it has been found that the concentrations of carrier proteins present can be altered, for example during pregnancy, oestrogen therapy and oral contraceptives. As the levels of carrier proteins change so does the amount of total T3 present, however, the free T3 (fT3) concentrations remain constant. For this reason alone, measuring free T3 levels correlates more reliably with clinical status in comparison to total triiodothyronine concentrations. The following FT3 ELISA kit procedure provides optimum sensitivity in the direct determination of f-T3 or free T3 whilst requiring minimum technical manipulations.


Current free triiodothyronine ELISA kit has a minimum sensitivity level of 0.05 pg/ml and this was derived by determining the variability of the 0 pg/ml serum calibrator and using the 95% certainty statistic in order to calculate the minimum dose.


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  • Full Name: Free Triiodothyronine (FT3) ELISA Kit
  • Reactivity: Human
  • Sample Type: Serum
  • Sensitivity: 0.05 pg/ml




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