Résumé
AIM Here the development of a simple, rapid and simultaneous method for the separation of five ephedrine alkaloids obtained with non-aqueous capillary electrophoresis (NACE) were reported. The effects of the electrolyte, non-aqueous solvent on the separation were also discussed. METHODS A running buffer of 50 mmol/L ammonium acetate in methanol was found to be the most suitable for this separation. RESULT The best separation was achieved within 8 minutes. CONCLUSION The separation is not only dependent on differences in the pK value of the alkaloids but also on the intramolecular interaction and solvation. So much improved selectivity could be achieved in nonaqueous medium.
Résumé
Object To develop a rapid method for the determination of ephedrine alkaloids in Ephedra sinica Stapf by nonaqueous capillary electrophoresis (NACE) and evaluate the extracting method by determining the amount of alkaloids Methods The buffer contained 50 mmol/L ammonium acetate in methanol without any additives was used And the detection wavelength was 210 nm Results The best separation result was achieved within 8 min Linearity was obtained in range of 9 8-147 0 ?g/mL pseudoephedrine, 6 8-102 0 ?g/mL for norephedrin, 9 4-141 0 ?g/mL for ephedrine, 4 8-72 0 ?g/mL for norpseudoephdrine, 6 8-102 0 ?g/mL for methylephedrine respectively The recovery range of these five alkaloids was 95 0%-100 4% Conclusion This method is rapid and accurate for the quantitative analysis of ephedrin alkaloids in E sinica