麻黄中麻黄生物碱的气相色谱测定法

本文应用毛细管气相色谱法,配备氮磷检测器对麻黄中六种生物碱:麻黄碱、伪麻黄碱、去甲麻黄碱、去甲伪麻黄碱、甲基麻黄碱和甲基伪麻黄碱进行分离、测定。对生药样品预处理方法作了较大改进,采用直接碱化醚提法。简化操作步骤。用内标法,线性方程定最测定了国产十二种麻黄,结果与高效液相色谱法基本一致。

DETERMINATION OF SIX EPHEDRA ALKALOIDS IN CHINESE EPHEDRA (MA HUANG)BY GAS CHROMATOGRAPHY

Six Ephedra alkaloids, namely ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedrine and methylpseudoephedrine, in 12 species of Chinese Ephedra were successfully separated and determined by gas chromatography with the highly specific and sensitive nitrogen phosphorus detector (GC/NPD). The column used (HP- 5)had a cross linked 5% phenylmethylsilicone phase. Diphenylamine was used as the internal standard to check the reproducibility of the extraction yields of the alkaloids, the stability of the detector response and to quantify the alkaloids. The contents of the six alkaloids were calculated according to their regression equations.The way for the preparation of crude drug samples was improved, the diethyl ether extract of the alkalized crude sample was directly analysed by GC.The method is simple, rapid and sensitive. The results are in agreement with those of the HPLC method.