The Specific Colorimetric Detection Of Metal Ions In Water By Nano-gold Modified With Triazole Ligand

Excessive metal can cause environmental pollution,and metal ion pollution in water is already very common.Because nano gold will have obvious color changes after aggregation,it is an ideal choice for colorimetric sensors.This paper studies the rapid detection technology of metal ions in water based on the principle of nanogold colorimetry.In this study,a series of triazole compounds were prepared by Click reaction,including 1-(pyridin-2-ylmethyl)-1H-1,2,3-triazole-4-carboxyIic acid.1-(2-(two)Ethoxyphosphoryl)ethyl)-1H-1,2,3-triazole-4-carboxylic acid.1-(carboxymethyl)-1,2,3-triazole-4-carboxylic acid,and methyl 1-(cyanomethyl)-1 H-1,2,3-triazole-4-carboxylate.The ligand-modified nanogold with controlled morphology and uniform paiticle size distribution was prepared by using the above compounds as ligands.Then,the selectivity and selection mechanism of different ligands and nanogolds for different metal ions were studied.It mainly consists of three parts:1.Preparation and characterization of triazole ligands:design and synthesis of a series of triazole ring compounds with different functional groups,characterized by NMR spectrometer.2.Preparation and characterization of triazole-modified nanogold:Ligand-modified nanogold was prepared by Brust method and characterized by UV-Visible spectrophoto-meter and transmission electron microscopy.3.Detection of metal ions by triazole-modified gold nanoparticles:The selectivity of different ligand-stabilized nanogolds to metal ions in water was detected by colorimetric method.The chelation of special functional groups on ligands was used to selectively and highly sensitively detect metal ions.Experiments show that FG3 stabilized gold nanoparticles(FG3-AuNPs)can achieve rapid visual detection of Al3+with a minimum detection limit of 1 ?M.At the same time.the mechanism study showed that Al3+and the FG3 have selective coordination,and the rapid detection was achieved by the coordination of nano-gold.The characterization means include ultraviolet visible spectrophoto-meter,transmission electron microscope and infrared spectrometer.