Optically-Controlled Preparation And Supramolecular Electrochemistry Sensing Performances Of Cyclodextrin-Modified Carbon Materials

There are abundant chemical substances in human body,including metabolites and physiologically active substances.Such as uric acid(UA),ascorbic acid(AA),dopamine(DA)and tyrosine(Tyr).Abnormal concentration of these physiologically active substances is commonly associated with various diseases.Therefore,it is of great significance to detect these biologically active molecules simultaneously with high sensitivity.Electrochemical technology has the advantages of high sensitivity,simple operation,low cost and quick response,so the quantitative analysis of these physiological active molecules by electrochemical analysis method has practical application value.The interface property of working electrode is the key factor of electrochemical sensing system.The electrochemical sensing performance of the electrode can be effectively improved by modifying functional materials on the electrode surface.Therefore,the construction of effective electrode materials is particularly important.The hydrophobic inner cavity of cyclodextrin can selectively combine with various guest molecules to form inclusion complexes and carbon materials have excellent electron conductivity and electrocatalytic properties.β-CD is combined with carbon materials and these materials are modified on the bare electrode in this paper,so as to achieve efficient sensing of AA,DA,UA and Tyr.The specific contents are as follows:1.The cyclodextrin-modified GO(GO-CD)was self-assembled with multi-walled carbon nanotubes(MWCNTs)in solution,and then the GO was reduced by polyoxometalate(POM)under UV light to produce RGO-CD-MWCNT-POM with a large number of active catalytic sites and three-dimensional porous structure.Then,the material was modified on the electrode to detect AA,DA and UA simultaneously by cyclic voltammetry,pulse voltammetry,square wave voltammetry and stripping voltammetry.The results show that RGO-CD-MWCNT-POM has high selectivity and low detection limit in voltammetry analysis.RGO-CD-MWCNT-POM is expected to be used for simultaneous determination of AA,DA and UA in real life.2.GO,cyclodextrin,and silver nitrate solution were ultrasonically recombined in onepot method.Then,GO and silver nitrate were reduced by POM.The reduction products were RGO and Ag NPs.RGO-CD-Ag-POM was synthesized by self-assemble.The material was modified on the electrode and UA and Tyr were detected simultaneously by cyclic voltammetry and pulse voltammetry,and the recovery rate of RGO-CD-Ag-POM in human urine was tested.The results showed that RGO-CD-Ag-POM is an excellent electrochemical sensing material and is expected to be used for the simultaneous determination of UA and Tyr in practical life.