Studies on Tritium-labeled Compounds. VI. The Platinum-catalyzed Exposure Technique

To increase the efficiency of labeling according to the Wilzbach procedure by absorbing the β-ray energy of tritium in the system, three typical hydrogenation catalysts were applied to the salicylic acid-T2 system. The platinum catalyst was found to be most effective in promoting the labeling. The results obtained in labeling six compounds by the platinum-catalyzed-exposure technique showed that by this procedure higher specific activities in the range of 3∼1880 fold were obtained. The increase in labeling changed considerably with different compounds, and the relative amount of labeling for aromatics was higher than for aliphatics.