固相萃取-气相色谱-质谱联用检测蔬菜中苄草隆残留及其断裂机理研究

Determination of Residual Cumyluron in Vegetable by Solid Phase Extraction with Gas Chromatography/Mass Spectrometry and its Fragmentation Mechanism Study

建立了固相萃取-气相色谱-质谱法检测蔬菜中的苄草隆残留的分析方法。样品用乙腈提取,经液液分配,Carb/NH2双层柱净化后过滤膜上机。采用选择离子扫描方式,外标法定量。本方法简便、快速,通过优化前处理和上机条件,在最优条件下进行测试,苄草隆的定量检出限为0.008mg/kg,在加标水平0.01~0.5mg/kg范围内,回收率为98%~122%;相对标准偏差为6.9%~14.2%。对苄草隆的质谱检测断裂机理进行了研究。

A method was developed for the determination of residual cumyluron in vegetable by gas chromatography/mass spectrometry （GC/MS）. The sample was extracted with acetonitrile, separated with liquid-liquid partition and purified by solid phase extraction （SPE）. After investigating the conditions of pretreatment and determination ,the method was convenient and rapid. Under the optimal conditions, the detection limits of cumyluron was 0.008 mg/kg,the recoveries for adding level in the ranges of 0.01 -0.5 mg/kg were 98% - 122% , the relative standard deviations were 6.9% - 14.2%. The fragmentation mechanism of cumyluron was also studied.