离子色谱法测定甘草提取物中草酸的含量

DETERMINATION OF OXALIC ACID IN LIQUORICE EXTRACT BY ION CHROMATOGRAPHY

建立了用离子色谱测定甘草提取物中残留草酸含量的新方法。选用DionexIonPacAS11-HC阴离子分析柱(250mm×4mmi.d.),淋洗液为18mmol/LNaOH溶液,流速为1.0mL/min,抑制电导检测器检测。草酸色谱峰面积(Y)与浓度(X)在1.004～10.04mg/L内线性关系良好,线性回归方程为Y=0.1939X-0.0326,相关系数r=0.9999,检出限为0.012mg/L。样品回收率为96.8%～98.6%,相对标准偏差为0.78%。该方法简便、快速。

A new method for the determination of oxalic acid in liquorice extract by ion chromatography was established. The separation of oxalic acid was obtained by using Dionex Ionpac AS11-HC (250 mm×4 mm i.d.) column and 18 mmol/L NaOH solution as the eluent. In the range of 1.004~10.04 mg/mL, the linear equation was Y=0.1939X-0.0326, the correlation coefficient was 0.9999. The detection limit was 0.012 mg/L. The average recoveries were 96.8%~98.6%, and the relative standard deviation was 0.78%. The method was simple, rapid and accurate.