Objective: To establish a method to examine the limited content of aristolochic acid A in Qingxueneixiao Pills. Method: 1% sodium carbonate solution is repeatedly heated to dissolve the sample

extracted with chloroform for several times. Discard the chloroform layer

adjusted the pH of the alkaline layer with dilute hydrochloric acid

and extracted with chloroform again for several times. Collect and evaporate the chloroform layer. The residue was dissolved in methanol

1 mL of which was diluted to 20 mL

eluted with a gradient composed by acetonitrile-water (40: 60)

water (0.1% formic acid+5 mmol·L-1 ammonium formate )/( %) and acetonitrile (containing 5% water

0.1% formic acid+5 mmol·L-1 ammonium formate )/( %)

assayed in high performance liquid chromatography/electrospray ionization mass spectrometry multiple reaction monitoring (MRM) mode. Result: Aristolochic acid A was linear int the range of 11.21-299.0 pg (r=0.999 5).The average recovery was 119.2% (n=9) and the RSD was 4.0%. Conclusion: This method is accurate

rapid

simple

reproducible

less interference and specific

appropriate to the trace detection for the Qingxueneixiao Pills.