Wang Shuangjie, Liu Ying, Jiao Shasha, Zhao Ying, Guo Yirong, Wang Mengcen, Zhu Guonian
Institute of Pesticide and Environmental Toxicology, Zhejiang University , Hangzhou, Zhejiang 310058, People's Republic of China.
J Agric Food Chem. 2017 Nov 22;65(46):10107-10114. doi: 10.1021/acs.jafc.7b03981. Epub 2017 Nov 8.
Neonicotinoid insecticides are commonly used for pest control on tea plantations as a result of their broad-spectrum activity. However, neonicotinoid residues released from tea leaves into tea infusions pose a dietary risk to consumers. Therefore, a rapid, sensitive, and reliable on-site detection method for neonicotinoids is needed. We developed a quantum-dot-based fluorescent lateral flow immunochromatographic strip (LFICS) combined with a broad-specific antibody for detection of typical neonicotinoids (imidacloprid, imidaclothiz, and clothianidin), with sensitivities [50% inhibitory concentration (IC)] of 0.104-0.33 ng/mL and visual detection limits of 0.5-1 ng/mL. The strip assay could be completed in less than 30 min. Using the LFICS to analyze spiked tea samples (green tea, black tea, and oolong tea), the average recovery of the three neonicotinoids ranged between 71 and 111%, with the coefficient of variation below 12%. The results from the LFICS tests for field samples were consistent with results from ultraperformance liquid chromatography-tandem mass spectrometry. The newly developed strip is a useful tool for the on-site detection of neonicotinoid residues in tea.
由于具有广谱活性，新烟碱类杀虫剂常用于茶园害虫防治。然而，茶叶中释放到茶汤中的新烟碱类残留会给消费者带来饮食风险。因此，需要一种快速、灵敏且可靠的新烟碱类现场检测方法。我们开发了一种基于量子点的荧光侧向流动免疫层析试纸条（LFICS），结合一种广谱特异性抗体来检测典型的新烟碱类（吡虫啉、啶虫脒和噻虫胺），灵敏度[50%抑制浓度（IC）]为0.104 - 0.33 ng/mL，目视检测限为0.5 - 1 ng/mL。试纸条检测可在30分钟内完成。使用LFICS分析加标茶样（绿茶、红茶和乌龙茶），三种新烟碱类的平均回收率在71%至111%之间，变异系数低于12%。现场样品的LFICS检测结果与超高效液相色谱 - 串联质谱法的结果一致。新开发的试纸条是现场检测茶叶中新烟碱类残留的有用工具。
