Valenzuela A I, Redondo M J, Pico Y, Font G
Laboratori de Toxicologia, Facultat de Farmàcia, Universitat de València, Burjassot, Spain.
J Chromatogr A. 2000 Feb 25;871(1-2):57-65. doi: 10.1016/s0021-9673(99)01190-5.
Liquid chromatography coupled to electrospray mass spectrometry (LC-ES-MS) with positive ion detection was used to determine abamectin in oranges. MS conditions were optimized to achieve maximum sensitivity. The main ion for abamectin was [M+Na]+ at a fragmentor voltage of 180 V. Abundant structural information can be obtained at different fragmentor voltages. The detection limit for the standard solution was 12 pg injected, and good linearity and reproducibility were observed. Abamectin residues were extracted using matrix solid-phase dispersion. Orange samples were homogenized with C18 bonded silica placed onto a glass column and eluted with dichloromethane. Recoveries of the abamectin from oranges fortified with approximately 0.01-10 mg/kg ranged from 94 to 99% with an overall average recovery of 96%. The quantification limit is 0.0025 mg/kg, which means detection limit for this analyte could be set at a few hundred picograms per gram of fruit. The presence in the electrosprayed solution of numerous citrus constituents did not interfere significantly with the ionization process of abamectin. The assay procedure provides a simple, rapid, and sensitive method for monitoring residues in oranges. The method was applied to field treatment orange samples.
采用正离子检测的液相色谱-电喷雾质谱联用仪（LC-ES-MS）测定橙子中的阿维菌素。对质谱条件进行了优化以实现最大灵敏度。阿维菌素的主要离子为在碎裂电压180 V时的[M+Na]+。在不同的碎裂电压下可获得丰富的结构信息。标准溶液的检测限为进样12 pg，观察到良好的线性和重现性。采用基质固相分散法提取阿维菌素残留。将橙子样品与置于玻璃柱上的C18键合硅胶匀浆，并用二氯甲烷洗脱。在添加量约为0.01 - 10 mg/kg的橙子中，阿维菌素的回收率为94%至99%，总体平均回收率为96%。定量限为0.0025 mg/kg，这意味着该分析物的检测限可为每克水果几百皮克。电喷雾溶液中众多柑橘成分的存在对阿维菌素的电离过程没有显著干扰。该分析方法为监测橙子中的残留提供了一种简单、快速且灵敏的方法。该方法应用于田间处理的橙子样品。
