Synthesis of 13С- and 14С-labeled linoleic acids for use in diagnostic breath tests for hepatobiliary system disorders
At present, there is a need for a simple, noninvasive, highly specific and sensitive diagnostic test for hepatobiliary system disorders. Compounds labeled with carbon isotopes are widely used in various diagnostic breath tests; they are safe and can reliably detect a metabolic disorder or enzyme deficiency. The aim of this study was to synthesize 13С- and 14С-labeled linoleic acids suitable for use in hepatobiliary breath tests in terms of purity. In the synthesis of 13С-labeled linoleic acid, the chemical yield for 1-bromo-8,11-heptadecadien was 86.4% and the chemical yield for barium carbonate-13С, 96.0%. In the synthesis of 14С-labeled linoleic acid, the chemical yield for 1-bromo-8,11-heptadecadien was 87.39%; for barium carbonate-14С it was 97.1%. The specific radioactivity of 14С-labeled linoleic acids was 45.36 ± 0.02 mCi/g. The radiochemical yield of the reaction was 96.0%. The proposed method is suitable for batch production.