摘要
使用水－界面膜－油体系通过物质具有不同的酸离解常数及透膜常数以提高电导滴定方法的选择性，对麻黄草中的混合生物碱进行了分步测定，终点明确。盐酸麻黄碱回收率９９．８％±０．８％。麻黄草中麻黄碱含量０．４１％、伪麻黄碱０．１０％，其余生物碱０．０６％，生物碱总量０．５８％，与ＨＰＬＣ法结果总体一致。
A water-interface membrance-oil system was developed to determine contents of alkaloids extracted from a crude drug, Ephedra Herba, by conductivity titration method. We determinated simultanously contents of Ephedrine and pscudoepherine in a mixture consisting of 100 mL of the water extract, certain amount of emulsifier on OP and 10 mL of benzene, due to the differences of the acid constant, Penetration membrance constant and distribution coeefficient in the oil-water phase between ephedrine and psludoephedrine. The equivalence point was easily discriminated. The recovery of ephdrine hydrochloride is 99. 8% ± 0. 8%. The contents of alkaloide in ephedra herba are as follows: ephedrine 0.41 %, pseudoephdrine 0. 10%, the rest 0.06%, and the total content 0.58%. The results are in correspondence with those obtained by HPLC on the whole.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2000年第8期1002-1005,共4页
Chinese Journal of Analytical Chemistry
关键词
乳液
电导滴定
麻黄
生物碱
中药
检测
Emulsion, conductometric titration, alkaloids ephdra herba
