1977 年 97 巻 11 号 p. 1263-1266
Berberine in Coptidis Rhizoma and Oriental pharmaceutical preparations was determined with a small standard deviation and a small coefficient of variation. The sample solution was separated by two-dimensional thin-layer chromatography on a plate (20×20 cm) with two different developing solvents, n-BuOH : AcOH : H2O=7 : 1 : 2, and cyclohexane : diethylamine=9 : 1. The berberine portion was scraped off from the plate and extracted with 1% HCl·methanol. The extract solution was placed in a test tube. After evaporation of the solvent, 5 ml of phosphate buffer (pH 8.0) and 2 ml of phosphate tetrabromophenolphthalein ethyl ester (TBPE) solution (4.0×10-4M) were added to the residue, and the solution was shaken with 5 ml of 1, 2-dichloroethane. Berberine was extracted into the organic layer as a 1 : 1 ion-pair complex with TBPE. Color of organic layer was yellowish green (λmax 610 nm). The quantitative determination of berberine in the range of 4.3-21.6 μg is possible by the mesurement of this coloration at 610 nm.