高效液相色谱-串联质谱法测定仙草及其产品中苯甲酸含量

Determination of benzoic acid in Mesona chinensis Benth and its products by high performance liquid chromatography-tandem mass spectrometry

建立了仙草及其产品中苯甲酸含量的高效液相色谱串联质谱检测方法。样品在酸性环境中,经乙醚液液分配提取,用岛津C18(2.1um,2.1×150mm)分离,以0.2mmol/L乙酸铵水溶液-乙腈等度洗脱,采用多反应监测(MRM)负离子模式检测,外标法定量。在0.1~2.0 mg/L范围内线性关系良好,相关系数0.9999;在0.1 mg/L、0.5 mg/L、1.5 mg/L加标水平的回收率为90.0%~98.0%,相对标准偏差2.1%~4.6%,检出限0.025 mg/kg,定量限为0.1 mg/kg。该方法简单、灵敏、稳定,可满足仙草及其产品中苯甲酸含量的检测和确证。

A high performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS） method was developed for determination of benzoic acid in Mesona chinensis Benth and its products. The benzoic acid was liquid- liquid Extraction by ether. The separation of the compound was carried on a C18 （2.1urn, 2.1 x 150mm） by a elution using acetonitrile and 0.2 mmol ammonium acetate aqueous solution as mobile phases and detected by tandem mass spectrometry in multiple reaction monitoring （MRM） mode with negative electrospray ionization. The benzoic acid was quantified by external standard method, The linear range was 0.1 - 2.0 mg/L and the correlation coefficient was 0.9999. The average recovery and relative standard deviation ranged from 90.0% - 98.0% and 2.1% - 4.6%, respectively at the spiked levels of 0.1, 0.5 and 1.5mg/L for the sample. The limit of detection was 0.025 mg/kg. The limit of quantitation was 0.1 mg/kg. The method is sensitive, accurate and suitable for the determination and confirmation of benzoic acid in Mesona chinensis Benth and its products.