Beijing Technology and Business University (BTBU), No. 11 Fucheng Road, Beijing 100048, People's Republic of China.
J Agric Food Chem. 2022 May 25;70(20):6059-6071. doi: 10.1021/acs.jafc.2c01568. Epub 2022 May 11.
In this paper, carbon dot (CD)-encapsulated 1,3,5-tris(4-formylphenyl)benzene (TFB)/2,5-dihydroxyterephthalohydrazide (DHTH) covalent organic frameworks (TDCOFs) grafted with thermoresponsive poly(-isopropylacrylamide) (PNIPAM) (CDs@TDCOFs@PNIPAM) were fabricated for the detection of pyrethroids. CDs@TDCOFs@PNIPAM achieved a temperature-responsive "on/off" detection of pyrethroids based on the target-triggered electron-transfer mechanism. The detection limit of pyrethroids was as low as 0.69 μg/L in the wide linear range of 5-400 μg/L ( > 0.9523). Simultaneously, CDs@TDCOFs@PNIPAM with red, green, and blue (RGB) fluorescence emissions were integrated with a smartphone-assisted device, enabling the visual smart quantitative detection of pyrethroids with a detection limit of 4.875 μg/L. Ultimately, agricultural products were chosen as actual samples to verify the applicability of both recognition modes, and the calculated recovery rate was 105.48-113.40%. Accordingly, CDs@TDCOFs@PNIPAM featuring temperature-responsive switching behavior and RGB fluorescence emission provided a promising analytical strategy for ensuring agricultural and food safety.
本文制备了碳点（CD）封装的 1,3,5-三（4-甲酰基苯基）苯（TFB）/2,5-二羟基对苯二甲酰肼（DHTH）共价有机框架（TDCOFs）接枝温敏聚（异丙基丙烯酰胺）（PNIPAM）（CDs@TDCOFs@PNIPAM），用于检测拟除虫菊酯。基于目标触发的电子转移机制，CDs@TDCOFs@PNIPAM 实现了拟除虫菊酯的温度响应型“开/关”检测。在 5-400 μg/L（>0.9523）的宽线性范围内，拟除虫菊酯的检测限低至 0.69 μg/L。同时，具有红、绿、蓝（RGB）荧光发射的 CDs@TDCOFs@PNIPAM 与智能手机辅助设备集成，实现了拟除虫菊酯的可视化智能定量检测，检测限低至 4.875 μg/L。最终，选择农产品作为实际样品来验证两种识别模式的适用性，计算出的回收率为 105.48-113.40%。因此，具有温度响应切换行为和 RGB 荧光发射的 CDs@TDCOFs@PNIPAM 为确保农业和食品安全提供了一种很有前景的分析策略。
