Determination of the Alkaloids in Coptis-Evodia Herb Couple by Capillary Electrophoresis

Abstract

A method combining the techniques of micellar electrokinetic capillary chromatography (MECC) and capillary zone electrophoresis (CZE) has been developed to assay seventeen alkaloids in coptis-evodia herb couple. The MECC method, based on SDS, was applied to analyze three indolequinazoline alkaloids and six quinolone alkaloids in evodia within 30 minutes, and a CZE technique was used to determine eight quaternary alkaloids (dehydroevodiamine in evodia, and seven protoberberine alkaloids in coptis) within 25 minutes. The recovery efficiencies were 96.68–103.19% in MECC and 99.65–103.28% in CZE, with a relative standard deviation of 1.67–4.00% for MECC and 2.33–4.38% for CZE. The calibration curves exhibited good linearity over one order of magnitude of concentration, and their minimum detectable concentrations were approximately 15.78 to 47.33 μ/mL using a 0.75 μ inner diameter column. Contents of the seventeen alkaloids in a methanol-water crude extract of coptis-evodia herb couple could easily be determined by this method.