Construction Of Electrochemical Sensor Based On MOFs For The Detection Of Phenolic Contaminants

The detection of phenolic endocrine disruptors has become a hotspot in the field of environmental research because of its strong estrogen effect,large chemical application and extensive pollution.So it is necessary to establish sensitive and efficient detection and analysis methods.Compared with traditional detection methods,electrochemical sensors are widely used for rapid detection of environmental pollution and emergency detection of environmental events due to the characteristics of simple operation,high sensitivity,low cost and easy construction.The lanthanide metal organic framework is widely used in biomedicine,small molecule detection,and ion detection due to its special structural characteristics and fluorescence characteristics,but there are few studies on its electrochemical properties.In this study,the electrochemical sensors based on lanthanide metal organic framework were fabricated for the rapid determination of bisphenol A(BPA)and bisphenol S(BPS)in the environment.The specific contents and results are as follows:(1)A electrochemical sensor based on the cerium metal organic frameworkelectrochemically reduced graphene oxide(Ce-MOF-ERGO)nanocomposite coupled with cetyltrimethylammonium bromide(CTAB)signal amplification was fabricated for rapid detection of bisphenol A(BPA).The Ce-MOF-ERGO nanocomposites provided sufficient reaction sites and electrocatalytic activity for BPA.In addition,adding CTAB to the supporting electrolyte was beneficial to reduce the electrochemical passivation of BPA and enhance the adsorption of BPA on the modified electrode surface,thereby further enhancing the oxidation signal of BPA.Under the optimal conditions,the electrochemical sensor had a linear response to BPA in the concentration range of 3 nmol/L to 10 ?mol/L,and its detection limit(LOD)was 1.9 nmol/L.Through a series of performance tests,the electrochemical sensor showed the advantages of high anti-interference,high stability and good reproducibility,and it exhibited good recovery and accuracy in the detection of real samples.(2)A new molecularly imprinted electrochemical sensor detecting BPS based on MIP-Eu-MOF-CNTs/GCE was fabricated by electropolymerizing a layer of polypyrrole film with specific imprinted holes on the surface of Eu-MOF-CNTs nanocomposites.Eu-MOF-CNTs composite materials provide sufficient support surface area for the polymerization of pyrrole and increase the recognition sites of molecular imprinting.The new molecularly imprinted electrochemical sensor had a good linear response of 0.05 ~ 50 ?mol/L.Through calculation,the detection limit of the sensor was 25 nmol/L.In addition,the electrochemical sensor exhibited excellent performance,including anti-interference and high stability and it also has good recovery and accuracy in the detection of real samples.