Enrichment and detection of aconitine-type toxic composition in Fuzi Lizhong pills

OBJECTIVE To set up a method of field-amplified sample stacking in capillary electrophoresis for fast detecting aconitine-type toxic composition in Fuzi Lizhong pills.METHODS Based on the character of acontine-type alkaloids,hydrochloric acid was added to remove fat-soluble impurities,then alkalified.After alkalization,the water-soluble impurities were removed by ethylether extraction.The running buffer was 50 mol·L-1 phosphate(pH8.5)-acetonitrile(6:4).The running voltage was 10 kV and the capillary inlet was dipped in water for 5 s prior to electro kinetic injection(12 kV,15 s).The detection wave length was 235 nm.RESULTS The calibration curves were linear in the ranges of 15.6-1.0×103 μg·L-1 for aconitine,31.3-2.0×103 μg·L-1 for hypaconitine.The recovery of Ac and HA were 98.7% and 97.1% with RSD of 3.1% and 2.1%,respectively.CONCLUSION A capillary electrophoresis with field-amplified sample stacking method was established and greatly improved the specificity and sensitivity of quantitative analysis,allowing 400 fold enrichment of detection sensitivity.It provided a new reliable and convenient strategy for limited determination of Fuzi Lizhong pills.