Identification, characterization and suppression of side-products formed during the synthesis of high dose 68Ga-DOTA-TATE

In the course of the establishment of Ga-68-DOTA-TATE production for clinical use a shoulder comprising presumably several impurities was observed in the chromatogram of the analytical radio-HPLC. LC-MS/MS results support the hypothesis that some of these radioimpurities are radiolytic oxidation by-products of Ga-68-DOTA-TATE. A new HPLC method was developed for quality control of Ga-68-DOTA-TATE. Significant improvement on the radiochemical purity of Ga-68-DOTA-TATE was achieved by the addition of ascorbic acid or ethanol to the reaction mixture. (C) 2012 Elsevier Ltd. All rights reserved.