Creative Chemistry and Innovation Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahasarakham University, Maha Sarakham 44150, Thailand.
Department of Chemistry, Faculty of Engineering, Rajamangala University of Technology Isan, Khon Kaen Campus, Khon Kaen 40000, Thailand.
Molecules. 2018 Apr 11;23(4):883. doi: 10.3390/molecules23040883.
In this work, we investigated montmorillonite for adsorption of neonicotinoid insecticides in vortex-assisted dispersive micro-solid phase extraction (VA-d-μ-SPE). High-performance liquid chromatography with photodiode array detection was used for quantification and determination of neonicotinoid insecticide residues, including thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid. In this method, the solid sorbent was dispersed into the aqueous sample solution and vortex agitation was performed to accelerate the extraction process. Finally, the solution was filtered from the solid sorbent with a membrane filter. The parameters affecting the extraction efficiency of the proposed method were optimized, such as amount of sorbent, sample volume, salt addition, type and volume of extraction solvent, and vortex time. The adsorbing results show that montmorillonite could be reused at least 4 times and be used as an effective adsorbent for rapid extraction/preconcentration of neonicotinoid insecticide residues. Under optimum conditions, linear dynamic ranges were achieved between 0.5 and 1000 ng mL with a correlation of determination () greater than 0.99. Limit of detection (LOD) ranged from 0.005 to 0.065 ng mL, while limit of quantification (LOQ) ranged from 0.008 to 0.263 ng mL. The enrichment factor (EF) ranged from 8 to 176-fold. The results demonstrated that the proposed method not only provided a more simple and sensitive method, but also can be used as a powerful alternative method for the simultaneous determination of insecticide residues in natural surface water and fruit juice samples.
在这项工作中，我们研究了蒙脱土对涡流辅助分散微固相萃取（VA-d-μ-SPE）中新型烟碱类杀虫剂的吸附作用。采用高效液相色谱-光电二极管阵列检测法对新型烟碱类杀虫剂残留量进行定量和测定，包括噻虫嗪、噻虫啉、吡虫啉、噻虫胺和噻虫砜。在该方法中，将固相吸附剂分散到水样中，然后进行涡旋搅拌以加速萃取过程。最后，用膜过滤器将溶液从固相吸附剂中过滤出来。优化了影响该方法萃取效率的参数，如吸附剂的用量、样品体积、盐的添加、萃取溶剂的类型和体积以及涡旋时间。吸附结果表明，蒙脱土至少可以重复使用 4 次，可作为新型烟碱类杀虫剂残留快速提取/预浓缩的有效吸附剂。在最佳条件下，线性动态范围为 0.5 至 1000 ng mL ，相关系数（r）大于 0.99。检出限（LOD）范围为 0.005 至 0.065 ng mL ，定量限（LOQ）范围为 0.008 至 0.263 ng mL 。富集因子（EF）范围为 8 至 176 倍。结果表明，该方法不仅提供了一种更简单、更灵敏的方法，而且还可以作为一种强大的替代方法，用于同时测定天然地表水和果汁样品中的杀虫剂残留。
