OBJECTIVETo establish a capillary electrophoresis with field-amplified sample stacking method for the separation and determination of aconitine alkaloid in Guifudihuang pills.

METHODAn uncoated fused-silica capillary column (50 microm x 43 cm, effective length 35 cm) was used. The running buffer was 50 mmol x L(-1) phosphate electrolyte solution (pH 4.6)-methanol (8:2). The runing voltage was 10 kV and the capillary inlet was dipped in methanol for 5 s prior to electrokinetic injection (10 kV, 40 s). The detection wavelength was 235 nm.

RESULTThis method allowed 500 fold enrichment of aconitine alkaloid. A good linear relation was obtained in the range of 31.3-2 x 10(3) microg x L(-1) (r = 0.9996), with the detection limit of 9.4 microg x L(-1). The average recovery was 98.0% with the RSD of 2.6%.

CONCLUSIONThe method is simple, rapid and specific with high stacking efficiency; it provides a new reliable means for production and quality control of Guifudihuang pills.