Abstract
The thin layer chromatographic separation of the thyroid hormones in human plasma, including l-thyroxin (T4), 3, 5, 3'-triiodo-l-thyronine (T3), 3, 5-diiodo-l-tyrosine (DIT), 3-monoiodotyrosine (MIT) and inorganic iodide (I-), was investigated. The stationary phase was Kieselguhr G (Merck) and the solvent system was n-butanol-chloroform (4:7) saturated with ammonia (ammonia atmosphere) at 32°C. The Rf values of pure thyroid hormones obtained were inorganic iodide 0.81, MIT 0.16, DIT 0.09, T3 0.57 and T4 0.36, respectively. The same Rf values were obtained when pure thyroid hormones were added to human plasma and extracted after modified Block's method. The radioautogram of the plasma extract of 131I-treated thyrotoxic patient showed corresponding radioactive spots with pure samples of T3, T4 and inorganic iodide on a thin layer chromatogram. The present method might be useful in studying the metabolism of thyroid hormone because of its many advantages such as shortness of development time, high sensitivity for detection, clear separation of each spot and simplicity of procedure.
