Adapting the total triiodothyronine [T3] radioimmunoassay kit to measure serum free T3
Rajan, M.G.; Samuel, A.M.
Indian Journal of Medical Research 87: 179-185
1988
ISSN/ISBN: 0019-5340 PMID: 3135263 Document Number: 317716
A simple method for measuring serum free triiodothyronine (FT3) by adapting the Bhabha Atomic Research Centre (BARC) T3 RIA kit is described. The underlying principle is based on column adsorption chromatography and RIA. The assay showed a sensitivity of 0.5 pg/ml and intra and inter-assay CV of less than 10 and 15 percent respectively over a range of 1.5-20 pg/ml. The performance of the assay was very similar to the commercial Liso-Phase FT3 kit and correlated very well with it. Good correlation was also seen between FT3 by the adapted technique and the ratio of T3 to thyroxine binding globulin in serum samples from normal individuals, hypo- and hyper-thyroid patients, pregnant women and some nonthyroidal ill patients.