高效液相色谱-三重四极杆质谱法测定克氏原螯虾中二甲戊灵残留

建立了高效液相色谱-三重四极杆质谱（HPLC-MS/MS）测定克氏原螯虾中二甲戊灵残留的分析方法。用含0.1%（v/v）乙酸的乙酸乙酯溶液提取克氏原螯虾中的二甲戊灵，于35℃旋蒸至干，经含0.1%（v/v）乙酸的甲醇-水（8∶2，v/v）溶解残渣后，用酸性氧化铝柱、石墨化炭黑（GCB）进行净化。采用Symmetry C18色谱柱（100 mm×2.1 mm，3.5 μm）进行分离，用加热大气压电喷雾电离（HESI）源、正离子模式进行扫描，在多反应监测模式（MRM）下检测。结果表明，二甲戊灵在1.0~20.0 μg/L范围内线性良好，相关系数为0.9960，检出限为0.2 μg/kg；二甲戊灵的加标回收率为63.3%~104.7%，精密度为6.9%~14.5%（n=7）。该方法简单、快速、灵敏度高，能够满足克氏原螯虾中二甲戊灵药物残留检测的需求。

Determination of pendimethalin residues in Procambarus clarkii by high performance liquid chromatography-triple quadrupole mass spectrometry

A novel method was developed for the determination of pendimethalin in Procambarus clarkii by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Samples were extracted with ethyl acetate containing 0.1%(v/v) acetic acid, and the extracts were dried at 35℃. The final extracts were redissolved with methanol-water (8:2, v/v) containing 0.1%(v/v) acetic acid and cleaned up by acidic alumina column and graphitized carbon black (GCB). The prepared samples were separated on a Symmetry C18 column (100 mm×2.1 mm, 3.5 μm) and characterized using a heated electrospray ionization (HESI) source in the positive ion multiple reaction monitoring mode. Under optimum experimental conditions, the standard curve was linear in the range of 1.0-20.0 μg/L with the correlation coefficient of 0.9960. The limit of detection was 0.5 μg/kg. The spiked recoveries of the pendimethalin in the Procambarus clarkii samples ranged from 63.3% to 104.7% with RSDs of 6.9%-14.5% (n=7). The proposed method is quick, simple and sensitive, and suitable for the rapid determination and analysis of pendimethalin in Procambarus clarkii samples.