A Novel And Efficient CuMOF-based Nanozyme And Its Application To Aptamer Coupled SERS/Fluorescence/RRS/UV Absorption Tetramodal Detection Of Malachite Green

Malachite green（MG）is highly toxic,persistent and carcinogenic.It is widely used to seriously endanger the ecosystem and threaten public health and food safety.It is necessary to build a new sensitive multimode molecular spectral analysis method.In this paper,copper based nano-materials（Cu NM）were prepared by high-temperature calcination using copper metal organic framework（Cu MOF）as precursor.The synthesized Cu NM materials were characterized by X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,transmission electron microscopy（TEM）and nitrogen adsorption desorption technology.It is found that Cu NM catalyzed the oxidation of 3,3’,5,5’-tetramethylbenzidine（TMB）with H₂O₂to produce the oxidation product TMB_OX and MG aptamer（Apt）can be adsorbed on the surface of Cu NM by intermolecular interaction,which will inhibit the catalytic performance of Cu NM.When MG is added,Apt and Cu NM are desorbed,and Cu NM are converted to free state,thus recovering its catalytic activity.This new nano-catalytic indicator reaction can be detected by SERS/RRS/fluorescence/Abs four-modes method.The results showes that the detection of MG had satisfactory selectivity and reasonable reproducibility.When the detection range is 0.004-0.4 nmol/L,the detection limit is 0.0032 n M.Therefore,a rapid,stable and sensitive method for the detection of malachite green residues in the environment is established.