高效液相色谱-二极管阵列检测器结合固相萃取法快速测定食品中米酵菌酸残留

Fast Determination of Bongkrekic Acid in Foods Using Mixed-Mode Weak Anion Exchange Solid Phase Extraction Coupled with High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD)

建立WAX混合型弱阴离子固相萃取富集净化,高效液相色谱-二极管阵列检测器快速测定食品中米酵菌酸残留的方法。采用C18色谱柱（4.6 mm×250 mm,5？μm）,以乙腈-甲醇-1%乙酸溶液（10∶62∶28,V/V）为流动相,以269 nm为分析波长,米酵菌酸在0.1～40 mg/L质量浓度范围内线性良好,相关系数r值大于0.999。本实验考察样品的提取条件及不同固相萃取小柱净化效果,结果表明,选择体积分数80%乙腈溶液为提取溶剂,超声提取30 min,WAX小柱富集、净化,效果最佳。方法检出限为0.03 mg/kg。通过不同样品加标验证,平均回收率为83.3%～95.6%,相对标准偏差不大于5%（n=6）。与GB/T 5009.189—2003《银耳中米酵菌酸的测定》方法相比,该方法精确灵敏、回收率高、前处理简单快速,适用于各种食品中米酵菌酸残留快速测定。

A method for the determination of bongkrekic acid（BKA） in foods was developed using mixed-mode weak anion exchange（WAX） solid phase extraction（SPE） combined with high performance liquid phase chromatography with diode array detection（HPLC-DAD）.BKA was separated on a C18 column using a mobile phase consisting of acetonitrile,methanol and 1% acetic acid aqueous solution（10：62：28,V/V）.There was a good linearity between the peak area of the analyte and its concentration in the range of 0.1–40 mg/L with a correlation coefficient of more than 0.999.The extraction solvent and conditions were investigated and optimized,and six SPE catridges were compared for their purification efficiencies.The best efficiency was achieved when samples were ultrasonically extracted with 80% acetonitrile in water for 30 min and the extract was cleaned up by WAX solid phase extraction.The limit of detection（LOD） of the method was 0.03 mg/kg.The mean recoveries of BKA from spiked samples were 83.3%–95.6% with relative standard deviation（RSD） less than 5%（n = 6）.Compared with the standard method,this method is more accurate and sensitive with higher recovery,requires a simpler and quicker pretreatment and thus,can be used for the determination of BKA in various food samples.