Yao Dongmei, Bi Huiling, Gong Huimin, Lai Hongfang, Lu Sufen
School of Chemical and Biological Engineering, Hechi University, Yizhou 546300, China.
Nanomaterials (Basel). 2022 Aug 19;12(16):2866. doi: 10.3390/nano12162866.
In this paper, covalent organic frameworks (COFs) are prepared by solvothermal synthesis using 1,3,5-benzenetricarboxaldehyde and benzidine as ligands. Then, using COFs as a template, AgCOFs with high catalytic activity is prepared by in situ loading silver nanoparticles (AgNC) on the surface of COFs by sodium borohydride reduction method. AgCOFs are characterized by TEM, SEM, FTIR and XRD. At the same time, the catalytic ability of AgCOFs for trisodium citrate-AgNO nanosilver reaction is studied. The results show that AgCOFs can catalyze the reaction of trisodium citrate-AgNO to generate silver nanoparticles (AgNPs). The solution color of the system gradually changes from colorless to yellow, and the absorbance value increases. Based on the catalytic reaction of AgCOFs and the regulation effect of nucleic acid aptamer reaction on AgCOFs, a new "on-off-on" colorimetric analysis platform is constructed and applied to the detection of trace Pb in water samples. This analytical platform is simple, sensitive and selective. Finally, the catalytic mechanism of the system is discussed to verify the feasibility of constructing a colorimetric analysis platform.
在本文中，以1,3,5-苯三甲酸醛和联苯胺为配体，通过溶剂热合成法制备了共价有机框架材料（COFs）。然后，以COFs为模板，采用硼氢化钠还原法在COFs表面原位负载银纳米颗粒（AgNC），制备了具有高催化活性的AgCOFs。通过透射电子显微镜（TEM）、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和X射线衍射（XRD）对AgCOFs进行了表征。同时，研究了AgCOFs对柠檬酸三钠-AgNO纳米银反应的催化能力。结果表明，AgCOFs能催化柠檬酸三钠-AgNO反应生成银纳米颗粒（AgNPs）。体系溶液颜色逐渐由无色变为黄色，吸光度值增大。基于AgCOFs的催化反应以及核酸适配体反应对AgCOFs的调控作用，构建了一种新型的“关-开-关”比色分析平台，并将其应用于水样中痕量Pb的检测。该分析平台具有简单、灵敏和选择性好的特点。最后，对体系的催化机理进行了探讨，验证了构建比色分析平台的可行性。
