Determination of active ingredients in hawthorn and hawthorn piece by capillary electrophoresis with electrochemical detection

Capillary-zone electrophoresis with electrochemical detection has been used for the separation and determination of (-)-epicatechin, rutin, hyperin, chlorogenic acid, and quercetin in hawthorn and hawthorn piece. The effects of several important factors, including the running buffer acidity, the separation voltage, and the working electrode potential, were evaluated to acquire the optimum analytical conditions. The working electrode was a 300-μm carbon-disk electrode at a working potential of +0.95 V (vs. SCE). Under the optimum conditions, the analytes can be well separated within 16 min in a 75-cm-long fused-silica capillary. The current response was linear over two orders of magnitude with detection limits ( S/N = 3) ranging from 6.00 × 10 −8 to 3.75 × 10 −7 g/mL for all analytes. The method was successfully used in the analysis of hawthorn and hawthorn piece and the assay results were satisfactory.