RESUMO
Objective:To establish a quantitative analysis method to determine the content of sulfurous anhydride in Rhizoma di-oscoreae by ion chromatography-direct extraction. Methods:Sulfurous anhydride was extracted by KOH solution (25 mmol·L-1). An IonPac? AS11-HC column(250 mm × 4 mm, 9. 0 μm) was used. The column temperature was 20℃, the eluent was KOH solution (20 mmol·L-1 ) at flow rate of 1. 00 ml·min-1 and the conductivity temperature was 20℃. Results:There was a good linear rela-tionship between the injection quantity (1.160-29.100 μg)and the peak area of sulfite(r =0.999 9). The average recovery was 98. 9%(RSD=0. 6%, n=9). The quantitation limit was 1. 38 ng·ml-1. Conclusion: The method is simple, accurate and rapid, which is appropriate for the quantitative analysis of sulfite anhydride in Rhizoma dioscoreae.