Spectrophotometric Determination of Quinine, Emethine and Ephedrine in Pharmaceutical Preparations with Tetrabromophenolphthalein Ethyl Ester by Solvent Extraction

概要

論文の詳細を見る
A singly charged tetrabromophenolphthalein ethyl ester (TBPE) anion was found to be extracted with alkaloids as 1 : 1 complexes in 1,2-dichloroethane. Of various solvents, TBPE-1,2-dichloroethane system gave a red color for alkaloids, while in the absence of alkaloids, an organic phase shows a pale yellow color. In this way, the spectrophotometric methods were investigated for the determination of a small amount of the alkaloids, such as quinine, emethine and ephedrine, by solvent extraction. Quinine is determined by measuring the absorbance of the extracts over a range from 0.5-5×10^<-6>M (0.20-1.98 μg/ml) at 555 nm. Emethine is determined from 2×10^<-6>M to 1×10^<-5>M (1.1-5.5 μg/ml) at 570 nm and ephedrine, from 1×10^<-6>M to 1×10^<-5>M (0.20-2.0 μg/ml) at 555 nm. From the conductivity measurements, it is concluded that red species in the extract is considered to be a kind of charge transfer complexes.
公益社団法人日本薬学会の論文
1976-06-25