高效液相色谱-串联质谱法检测新鲜蔬菜中的氯酸盐残留

Determination of chlorate residue in fresh vegetables by high performance liquid chromatography-tandem mass spectrometry

目的建立高效液相色谱-串联质谱(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)检测新鲜蔬菜中氯酸盐的分析方法。方法称5 g样品,分别用5 mL乙腈提取2次,合并提取溶液,定容,无需净化步骤,选择Hypercarb多孔石墨化碳色谱柱作为固定相,1%乙酸-水溶液和1%乙酸-甲醇溶液作为流动相进行梯度洗脱色谱分离,然后采用电喷雾离子化三重四极杆串联质谱测定。结果氯酸盐在0.0025~0.2 mg/L范围内峰面积与质量浓度的线性关系良好,相关系数(r^2)大于0.999;平均回收率为72.9%~100.2%,相对标准偏差为1.8%~6.2%,氯酸盐的定量限为0.01 mg/kg。结论该方法简单快速、准确可靠、成本低廉,适合新鲜蔬菜中氯酸盐的测定。

Objective To establish a method for the determination of chlorate residue in vegetables by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).Methods The sample(5 g)was extracted by 5 mL acetonitrile twice,and extraction solution was mixed without further cleanup.Hypercarb column was used as stationary phase,and the mixture of 1%acetic acid-water solution and 1%acetic acid-methanol solution mixed in different ratios were used as mobile phases in gradient elution.The analyte was determined using a triple quadrupole mass spectrometry equipped with an electrospray ionization source operated in the negative ion mode.Results The linear relationship between the peak area and the mass concentration of chlorate was good in the range of 0.0025-0.2 mg/L,and the correlation coefficient(r^2)was greater than 0.999.The mean recoveries of chlorate were 72.9%-100.2%with relative standard deviations of 1.8%-6.2%.The limit of quantification of chlorate was 0.01 mg/kg.Conclusion This method is simple,fast,accurate,reliable,low-cost,and is suitable for detecting chlorate in fresh vegetables.