1956 年 76 巻 6 号 p. 629-631
Separation of caffeine, theophylline, theobromine, 3-methylxanthine, and xanthine by paper partition, buffered paper, and circular paper chromatography was examined. Numerous developing solutions were used but the best results in separation were obtained from butanol saturated with 0.1% ammonia and a 7:1 mixture of isopropanol and 0.1% ammonia water. Better separation of theophylline and theobromine was effected by developing on a paper treated with Sørensen's buffer of pH 3-8. For circular paper chromatography, circular filter paper of 18cm. diameter, using the Giri method, was employed and by developing with the foregoing solutions, five kinds of xanthine derivatives were clearly separated in about 7 hours. The use of a short-wave ultraviolet light of 240-270mμ made it possible to detect caffeine, theophylline, and theobromine up to 0.5γ, and 3-methylxanthine and xanthine up to 0.1γ.