School of Chemistry, Sun Yat-sen University, Guangzhou, P. R. China.
J Sep Sci. 2019 Apr;42(7):1432-1439. doi: 10.1002/jssc.201801299. Epub 2019 Feb 7.
A novel hybrid triazine-imine core-shell magnetic covalent organic polymer with high adsorption capacity and excellent stability was fabricated by surface-assisted in situ growth technique. The composite possesses porous and extended π-conjugated system, and was applied as the magnetic sorbent for efficient enrichment and rapid separation of pesticides. A new analytical method for simultaneous determination of eight pesticides in fruit samples was developed by magnetic solid phase extraction combined with ultra high performance liquid chromatography and tandem mass spectrometry. The effect of extraction time, desorption time, and the type of desorption solvent on the extraction efficiency were evaluated. The established method shows good repeatability and high sensitivity. The repeatability of this method was estimated with relative standard deviations in the range of 0.7-7.0% (n = 5) for the same batch, and 1.7-10% (n = 3) for batch to batch. Good linearity for eight pesticides was obtained with coefficient of determination in the range of 0.9942-0.9990. Limit of detections ranged from 0.4 to 1.2 ng/L. Real sample determination showed that four and two pesticides were detected in strawberry and grape, respectively. The results demonstrated that the established method was efficient, sensitive, and convenient for trace determination of pesticides in fruit samples.
通过表面辅助原位生长技术，制备了一种具有高吸附容量和优异稳定性的新型杂三嗪-亚胺核壳磁性共价有机聚合物。该复合材料具有多孔和扩展的π共轭体系，被用作磁性吸附剂，用于高效富集和快速分离农药。通过磁固相萃取结合超高效液相色谱-串联质谱法，建立了一种同时测定水果样品中八种农药残留的新方法。考察了萃取时间、解吸时间和解吸溶剂种类对萃取效率的影响。该方法具有良好的重现性和高灵敏度。该方法的重复性以同一批样品的相对标准偏差在 0.7-7.0%（n=5）范围内，批间重复性在 1.7-10%（n=3）范围内进行评估。八种农药均具有良好的线性关系，相关系数在 0.9942-0.9990 范围内。检出限范围为 0.4-1.2ng/L。实际样品测定结果表明，草莓和葡萄中分别检测到四种和两种农药。结果表明，该方法高效、灵敏、方便，可用于水果样品中农药的痕量测定。
