Rapid determination of diterpenoids in Andrographis paniculata by microemulsion electrokinetic capillary chromatography with short-end injection

摘要

A rapid, simple, and reliable method has been developed for routine capillary electrophoretic analysis of two diterpenoids, andrographolide and dehydroandrographolide, in Androgrophis paniculata. For this system, using ethyl acetate oil-based microemulsion electrokinetic chromatography (MEEKC) and the short-end injection technique, analysis was complete in less than 2.5 min. In method validation the relative standard deviations of migration time and peak area of the two constituents were, respectively, 0.54% and 1.70% for andrographolide and 0.45% and 2.11 % for dehydroandrographolide. Regression equations revealed linear relationships (correlation coefficients 0.9994 for andrographolide and 0.9993 for dehydroandrographolide) between peak area and concentration. The effects of buffer pH, borate concentration, SDS concentration, co-surfactant type and concentration, injection time, and running potential were systematically investigated. The method can be successfully implemented in routine quality-control testing.