Determination of Residual Sulfur Dioxide in Fritillaria thunbergii Miq. by Ion-chromatography Method

OBJECTIVE To establish an ion-chromatography method for determination of residual sulfur dioxide in Fritillaria thunbergii Miq. METHODS The samples were analyzed by Dionex ICS-3000 ion-chromatography after distilled by steam, absorbed by 3% hydrogen peroxide. RESULTS The linear range of sulfate radical was 0.000 05-2 mg(r=1.000). The average recovery was 97.8% with the RSD of 2.1%(n=9). CONCLUSION The method is rapid, simple, sensitive, which shows good precision and reproducibility. It is suitable for determination of residual sulfur dioxide in Fritillaria thunbergii Miq.