高效液相色谱-串联质谱法测定豆芽中4-氯苯氧乙酸钠

Determination of sodium parachlorophenoxy in bean sprouts by high performance liquid chromatography-tandem mass spectrometry

目的建立豆芽中4-氯苯氧乙酸钠的液相色谱-串联质谱测定方法。方法豆芽样品均质后以0.01mol/L氢氧化钠溶液提取,提取液经酸化后再用乙酸乙酯萃取,收集经离心分层的有机相,浓缩后用甲醇溶解进行测定分析。以甲醇和0.1%甲酸(FA)水溶液为流动相,采用Hypersil GOLD a Q(100 mm×2.1 mm,3μm)色谱柱分离,电喷雾电离负离子条件下以选择反应监测模式(SRM)检测。结果该方法检出限0.005 mg/kg,在1~100 ng/m L范围内具有良好线性,相关系数为0.9998。回收率为79.1%~104.7%,相对标准偏差低于5%(n=6)。结论该方法前处理简单快速,定性准确,灵敏度好,适用于豆芽中4-氯苯氧乙酸钠的残留检测。

Objective To establish a method for determination of sodium parachlorophenoxy(4-CPANa) in bean sprouts by high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS). Methods The soybean sample was extracted with 0.01 mol/L sodium hydroxide solution, and the extracting solution was recovered by diethyl ether in acidic condition. After centrifugation, the organic phase was concentrated completely and re-dissolved with methanol. The sample was separated by a Hypersil GOLD a Q column(100 mm×2.1 mm, 3 μm) with methanol and 0.1% FA aqueous as mobile phase. The remnant was detected by MS/MS using H-ESI technology(negative ion mode) and SRM detection mode. Results The detection limit was 0.005 mg/kg and the linear range was 1~100 ng/m L with correlation coefficient(r2) of 0.9998. The average recoveries were between 79.1%~104.7% with relative standard deviation(RSD) less than 5%(n=6). Conclusion This analytical method is sample, rapid, accurate, and sensitive, and can be used for the rapid detection of sodium parachlorophenoxy in bean sprouts.