Preparation And Application Of Electrochemical Biosensors Based On Gold Nanoparticles

In recent years,nano-gold antibiosis and Au nanoparticles(AuNPs)have received extensive attention from researchers and have obtained many research results of applied value in the substrate material biosensors.In spite of this,several problems need to be solved in the field of nanogold antibacterial and nanogold biosensors:More effective evaluation methods for nanogold antibacterial should be developed,because it is still limited to traditional spectrophotometry(OD600 method)or fluorescent staining;Nanogold biosensors usually require the label complexes when they detect biological macromolecules.In order to solve the above problems,this paper mainly carried out the following two aspects:(1)A novel label-free electrochemical detection method based on nanogold structure was constructed.The main task divides into two fields:First,a molecularly imprinted biosensor for AFP protein was built through the good surface activity of AuNPs and interactions with AFP protein molecules.On this basis,based on the construction of AuNPs-based bacterial electrochemical impedance sensor,a highly sensitive measurement of E.coli DH5a bacteria without labeling was achieved,with a correction factor of R2 = 0.998.(2)Nanogold molecularly imprinted nucleic acid aptamer electrochemical sensors were developed to achieve highly sensitive detection of alpha-fetoprotein(AFP).Following is two different biosensors:Firstly,the molecularly imprinted biosensor for AFP protein used the good surface activity of AuNPs and the interaction with AFP protein molecules.On this basis,because of the strong interaction between gold and sulfhydryl groups,the aptamer of the AFP protein with a sulfhydryl group was coupled,and the dual roles of molecular imprinting and aptamer-specific binding to AFP were used to target AFP.With high-sensitivity protein detection,its linear detection range is lfg/ml-100ng/ml.In summary,the electrochemical biosensor based on nanogold has achieved high sensitivity detection of DH5a bacteria and AFP protein.The research results provide new research ideas for exploring the application of gold nanoelectrochemical biosensors in different fields and experimental support.