State Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Chemical Engineering and Materials Science, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin, 300071, China.
Mikrochim Acta. 2021 Apr 20;188(5):167. doi: 10.1007/s00604-021-04813-1.
A novel fluorometric method based on bipyridine-linked three-dimensional covalent organic frameworks (COFs) was developed for the determination of Co. The COFs were synthesized by the polyreaction of tetrakis(4-aminophenyl)methane (TAPM), 2,2'-bipyridine-5,5'-diamine (Bpy), and 4,4'-biphenyldicarboxaldehyde (BPDA) under solvothermal conditions. The fluorescence of the COFs, with excitation/emission peaks at 324/406 nm, is quenched by Co. Under the optimal conditions, the fluorescence quenching degrees (F-F) of the resulted COFs linearly enhance as the concentrations of Co increase in the range 0.01 to 0.25 μM, and a limit of detection of 2.63 nM is achieved. The fluorescence response mechanism was discussed in detail. This proposed approach has also been successfully employed to determine Co in complex samples (shrimp and tap water), and satisfactory recoveries (88.1 ~ 109.7%) was obtained. The relative standard deviations are below 4.9%.
一种基于联吡啶连接的三维共价有机框架（COFs）的新型荧光测定法被开发用于测定 Co。COFs 通过在溶剂热条件下聚合四（4-氨基苯基）甲烷（TAPM）、2,2'-联吡啶-5,5'-二胺（Bpy）和 4,4'-联苯二甲酸二醛（BPDA）来合成。COFs 的荧光（激发/发射峰在 324/406nm）被 Co 猝灭。在最佳条件下，所得 COFs 的荧光猝灭程度（F-F）随 Co 浓度在 0.01 至 0.25μM 范围内线性增加，检测限达到 2.63nM。详细讨论了荧光响应机制。该方法还成功地用于测定复杂样品（虾和自来水）中的 Co，获得了令人满意的回收率（88.1~109.7%）。相对标准偏差低于 4.9%。
