Determination of Free Triiodothyronine by Chemiluminescent Enzyme Immunoassay

The methodology based on chemiluminescent enzyme immunoassay was established for the determination of free Triiodothyronine (FT3). The HRP-luminol-H2O2 chemiluminescent system with high sensitivity was chosen as the detection system. The linear range was 0.90–80 pg ml−1. Under the selected conditions, the CVs of intra- and inter- assays were less than 15%. When the method was applied to detect free triiodothyronine in human serum, the diagnostic accordance rate of the method for hyperthyroidism was 83.3%. Compared with the commercial kit, the correlation coefficient was 0.9005. All the conditions chosen were to maintain the equilibrium between the free and the bound hormones to improve the validity of the experimental result.