固相萃取-离子色谱法测定中药萝芙木中常见有机酸和阴离子

Determination of common organic acids and inorganic anions in rauvolfia plants by solid phase extraction-ion chromatography

采用固相萃取-电导抑制离子色谱法测定了萝芙木中常见有机酸和无机阴离子。以Ionpac AS11为分离柱,Ionpac AG11为保护柱,萝芙木样品过IC SPE-C18前处理柱去除杂质和有机物,在确定的色谱条件下,柱温30℃,淋洗液为7.5 mmol/L Na OH溶液,流速为0.7 m L/min,电导检测器-离子色谱法直接测定样品,方法的相关系数在0.9987~0.9999之间,样品回收率在83.0%~100.8%之间,RSD〈5%。方法适用于中草药中常见有机酸和无机阴离子含量的测定。

A method was developed for the determination of common organic acids and inorganic anions in Rauvolfia plants by ion chromatography combining with solid phase extraction. The analytes were separated on an Ionpac AS11 anion and organic acid analytical column with Ionpac AG11 guard column. The Rauvolfia plants sample was purified by IC SPE-C18 pretreatment column for removing insoluble and organic impurities. Column temperature was 30℃. The sample was separated on an anion exchange column using 7. 5 mmol/L Na OH as mobile phase at flow rate of 0. 7 m L/min detected by a conductivity detector. The coefficient of the linear regression equation was 0. 9987 ~ 0. 9999. The recovery rate was 83. 0% ~ 100. 8% with RSD% ≤5%. This simple and accurate method is applicable to the determination of common organic acids and inorganic anions in Chinese herbal medicines.