用替代对照品羟苯乙酯高效液相色谱方法测定大蒜辣素

大蒜辣素极不稳定,制备供含量测定用对照品非常困难。大蒜辣素在溶液中相对稳定,用高效制备液相色谱制备高纯度的大蒜辣素溶液(>99%),HPLC-ESI-MS/MS和NMR法鉴定该溶液中主成分大蒜辣素的结构,用衍生化紫外分光光度间接测定法和EP5.0收载的类似方法分别测定该溶液含量,确定该溶液中大蒜辣素的含量为0.719mg/mL。以此溶液为基准,在条件为:AlltechC18柱(250mm×4.6mm,5μm),流动相为甲醇-0.4%甲酸(65∶35),流速为1.0mL/min,检测波长242nm,考察性质稳定而又易得的羟苯乙酯与大蒜辣素之间的校正因子。结果显示,测得1mg羟苯乙酯相当于4.71mg的大蒜辣素,该换算关系适用于大蒜辣素为0.018～2.9g/L的浓度范围,该方法与EP5.0的方法相比,分析时间明显缩短。

High Performance Liquid Chromatographic Method for the Determination of Allicin Using Ethylparaben as Substitute of Allicin Reference Standard

A HPLC method that use ethylparaben as substitute of allicin reference standard was established for the determination of allicin.A allicin solution(purity >99%)collected by preparative HPLC,was used as reference solution to determinate the corrective factor between alliicin and ethylparaben in a special HPLC system.The analyzing time of the roposed method was shortened from about 30 min to about 10 min.This shows ethylparaben is better than buthylparaben as a substitute of allicin reference standard.The method can be applied to the determination of allicin content range from 0.018 to 2.9 g/L.The method is simpler and more rapid and more promising than EP5.0 method.