RADIOPHARMACEUTICAL PREPARATION OF 3-123-I-ALPHA-METHYLTYROSINE FOR NUCLEAR-MEDICAL APPLICATIONS

α-Methyltyrosine was iodinated in position 3 of the aromatic ring by means of an electrophilic iodination method using chloramine-T in a phosphate buffer solution. In a mixture containing α-methyltyrosine, chloramine-T and a small amount of NaI as a carrier the reaction was complete within 15 min at room temperature. After purification by radio high pressure liquid chromatography /HPLC/ radiochemical yields of 77.6±3.2% were obtained. Radiochromatograms also revealed a small amount of an impurity, probably chlorinated 3-123I-α-methyltyrosine. After dissolving in isotonic phosphate buffer and sterile filtration the solution was ready for nuclear-medical applications. © 1990 Akadémiai Kiadó.