The Research Of MEMS Electrochemical Electrode Array For Rapid Detection Of Escherichia Coli

Objective:Escherichia coli is one of the foodborne intestinal pathogenic bacteriawhich could cause serious damage to human health, to achieve rapiddetection of Escherichia coli is one of the keys to prevention and control offoodborne disease；Several rapid detection techniques have been used forpathogen detection, including PCR and ELISA, Because of PCR andELISA detection need the enrichment, separation, morphology,biochemistry and serological tests to identify food pathogenic bacteria,Which need less time than the traditional method, still can not meet thepractical requirements.Electrochemical biosensors are famous to its fast detecting speed, lowenergy consumption, which are better than that of other detectiontechnologies. It as a kind of detection methods has becoming the importantdevelopment trend of detecting foodborne pathogenic bacteria.Electrochemical biosensor is mainly made up of two key parts, he firstone is biological sensing interface, which contains biological molecularrecognition layers and the other one is the transducer, which is thefoundation for constructing biological sensing interface. Traditionaltransducer (Electrode) system is too complicated, which including largereaction fluid volume (5-30ml), small samples testing and it takes at least10minutes to finish electrode surface pretreatment. In order to overcomethe shortage of traditional pathogenic bacteria detection method and realize the electrochemical biosensor detection technology application well inrapid detection of Escherichia coli, the purpose of this article focus on thepreparing of electrochemical electrode array based on MEMS, which willfully enhance the detection speed of electrochemical biosensor and achieverapid detection of E. coli.Methods:1.By means of technologies of corrosion, linkage, Photolithography,oxidation diffusion and sputtering, the array which contains16three Auelectrodes was fabricated on an optical glass.2.In the electrochemical electrode surface to construct single molecularself-assembled layer of11thiol undecanoic acid-BPA,then Fixed specificityof E. coli DNA probe sequence on the surface of single molecularself-assembled layer.3.To study the base performance of electrochemical electrode array andModification process were characterized by cyclic voltammetry (CV),chronoamperometry (IT) and AC impedance method(EIS).4.Implementation of rapidly detection of E.coli16SrDNA targetmolecules on the good performance of electrochemical electrode arrayResults:1.The variations were less than3.7%among16Au electrode units. Ittook only1min of the pretreatment and the reaction liquid volume was1-50μL. The Rct was28of the electrochemical array.2. Functionalized electrochemical array was used to detect the specificmolecule sequence of Escherichia Coli with a low detection limit of1×10-8mol/L.3.It was proved that electrochemical array with a superior practicability, its surface could be easily functionalized and could satisfythe need of multichannel trace detection.