将大气压固体分析探头离子源(ASAP)与多级质谱耦合(ASAP-MS/MS),在无需净化或浓缩等前处理及无需色谱分离的条件下,建立了蔬菜中13种农药残留的乙腈提取直接质谱分析方法,单个样品检测在数分钟内即可完成.针对常压直接分析质谱易受环境影响和上样精度差的问题,对ASAP电离源条件如脱溶剂气温度、电晕放电电流、样品溶液组成和进样模式等进行了优化；采用多反应监测扫描(MRM),通过产物离子丰度比进行定性,用内标标准曲线法定量；对韭菜、油菜和芹菜3种基质进行了考察,结果表明存在明显的基质效应.本方法在5.0～500 μg/L浓度范围内的线性相关系数均高于0.995,检出限为0.04～0.89μg/kg,精密度(RSD,n=7)为5.1％～13.0％.超高效液相色谱-电喷雾串联质谱法对实际样品的检测结果与ASAP-MS/MS的检测结果一致.该方法分析速度快,灵敏度高,无需有机溶剂且结果可靠,可应用于大批量农药残留的筛查和应急监测任务.%A rapid direct-analysis method using atmospheric pressure solids analysis probe coupled to tandem mass spectrometry (ASAP-MS/MS) was established for the detection of thirteen commonly used multi-class pesticides in vegetables,without cleanup,concentration or chromatographic separation,and a single run can be done in minutes.To compensate for the poor precision and instability in ambient ionization technique,ASAP source parameters of the corona discharge,desolvation gas temperature,sample solvent and sample-load mode were optimized.The target compound was identified by product ion abundance ratios in multiple reaction monitoring(MRM) mode and semi-quantified through internal standard calibration curves.The matrix effects of celery,leek and rape were analyzed,and had apparent influences.Under the optimal conditions,the linear range was 5.0-500 μg/L with a coefficient of above 0.995.The limit of quantification (LODs) of analytes were 0.04-0.89 μg/kg,with a precision of 5.1％-13.0％ (n =7).The real sample determination shows that the results by ASAP-MS/MS were in accordance with those obtained by ultra performance liquid chromatography coupled to tandem mass spectrometry(UPLC-MS/MS).The proposed ASAP-MS/MS technique can be a powerful tool due to its convenience,rapid,reliable,low-cost and eco-friendly for pesticide screening and emergency monitoring.
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