High-Performance Liquid Chromatographic Determination of Organic Substances by Metal Chelate Derivatization. III. Analysis of Ephedra Bases

High-performance liquid chromatographic (HPLC) analysis of ephedrine, pseudoephedrine, norephedrine and pseudonorephedrine in some Ephedra species was carried out. Color reaction of these bases by the formation of Ni (II) dithiocarbamate chelates facilitated microdetermination of these based at levels of less than 1 ng. This method was applied to the analysis of these bases in some Ephedra species. The present method is so sensitive that analysis of these bases in Pinelliae Tuber was also possible, and peaks corresponding to pseudoephedrine, norephedrine and pseudonorephedrine appeared on the chromatograms along with the peak of ephedrine.