QuEChERS结合超高效液相色谱-串联质谱法测定砂仁中4种黄曲霉毒素

Identification of Four Aflatoxins in Fructus amomi using QuEChERS Combined with Ultra-performance Liquid Chromatography-tandem Mass Spectrometry

摘要:

该研究建立了利用QuEChERS-超高效液相色谱串联质谱（UPLC-MS/MS）法同时测定砂仁中4种黄曲霉毒素（Aflatoxin B1、B2、G1、G2）的分析方法。通过对QuEChERS前处理技术、色谱和质谱条件的优化，确定了最佳的实验条件。研磨后的样品经φ=1%甲酸酸化的乙腈提取，无水硫酸镁及氯化钠脱水盐析，上清液经十八烷基键合硅胶（C18）、乙二胺-Ｎ-丙基硅烷（PSA）、无水硫酸镁混合吸附剂净化。经ACQUITY UPLC HSS T3色谱柱（1.8 µm，2.1 mm×100 mm）进行分离，以乙腈和φ=0.1%甲酸-5 mmol/L乙酸铵溶液进行梯度洗脱。在正离子模式下，进行多反应监测（MRM），进一步通过空白基质标准溶液外标法定量。结果表明，4种黄曲霉毒素在0.20~10.00 μg/L范围内线性关系良好，相关系数均大于0.998 9。实际样品的加标回收试验结果显示，回收率范围为89.50%~113.12%，日内精密度为1.31%~6.71%，日间精密度为1.29%~6.20%，4种黄曲霉毒素的方法检出限为0.30~0.60 μg/kg、定量限为1.00~2.00 μg/kg。该方法操作简单，快速，灵敏，适用于砂仁中4种黄曲霉毒素的定性、定量筛查。

Abstract:

A quick, easy, cheap, effective, rugged, and safe solid phase extraction (QuEChERS), in combination with ultra-high performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) was established to identify four aflatoxins in Fructus amomi. Optimal experimental conditions were determined by optimizing the QuEChERS pre-treatment technique and the chromatographic and mass spectrometric conditions. The samples were extracted using acetonitrile with 1% formic acid and salted out with anhydrous magnesium sulfate and sodium chloride, then purified using C18, primary secondary amine (PSA), and magnesium sulfate anhydrous. The target analytes were separated on Waters HSS T3 columns (1.8 µm, 2.1 mm×100 mm), eluted by acetonitrile and a 0.1% (V/V) formic acid-5 mmol/L ammonium acetate solution gradient elution was used. Results were detected using MS/MS in positive ion mode under multiple reaction monitoring (MRM); quantification was further conducted using matrix-matched external standard calibrations. Good linearities for the four aflatoxins in the range of 0.20~10.00 μg/L were obtained and the correlation coefficients were >0.998 9. The recoveries were 89.50%~113.12%. The intraday relative standard deviations (Intra-RSDs) and interday relative standard deviations (Inter-RSDs) were 1.31%~6.71% and 1.29%~6.20%, respectively, as determined using spiked samples. The limits of detection and limits of quantification were 0.30~0.60 μg/kg and 1.00~2.00 μg/kg, respectively. The method is simple, rapid, and sensitive. It can be used for the qualitative determination and quantitative analysis of four aflatoxins residues in Fructus amomi.