Construction And Application Of 3D Micro-nano Electrochemical Biosensing Interface

Early detection of cancers play an important role in the diagnosis of disease.Some researchs have shown that many diseases are related to the over expression of substance of cancer cells.Therefore,it's great significance for the real-time monitor cancer cells.In recent years,the application of three-dimensional(3D)biological micro-nano interfaces in chemistry,bioscience and nano materials fields have drawn great attention to researchers.The use of 3D micro-nanomaterials to develop electrochemical biosensors shown obvious advantages over two-dimensional nanomaterials,which can capture more cells.At the same time,3D materials with advantages of great biocompatibility,good conductivity and easy to be modified.These conditions are very favorable to establish electrochemical biosensors with good performance.Electrochemical biosensors are widely used in the detection of disease markers because of the low detection line,high sensitivity,fast response and low cost.Therefore,we designed several different types of 3D sensor interfaces to detect some disease markers in cancer cells.The main research works are as follows:1.CS-Au/hPPy composite micro-nanotube films were prepared by a simple electrodeposition method.CS-Au NPs were modified into hPPy tubes due to their good biocompatibility of chitosan(CS)and gold(Au),and the 3D structure of tubular polypyrrole(hPPy)support high conductivity and large specific surface area to CS-Au NPs.Then,CS-Au/hPPy micro-nanotube membrane was prepared,and the electrochemical cytosensor was constructed to detect the expression of sialic acid(SA)on the surface of A549 cells membrane.The results show that the cytosensor exhibit high sensitivity,wide range linear and low detection limit.At the same time,the electrochemical cytosensor also shows good stability,reproducibility and anti-interference.2.The MnO2/hPPy composite micro-nanotube films were prepared by electrodeposition.The 3D structure of hPPy,with the good conductivity and large specific surface area,large of MnO2NPs based on hPPy tube membrane make great electrocatalytic activity to hydrogen peroxide(H2O2),and the detection of H2O2 in A549 cells was successfully implemented.The sensor shows great electrochemical performance,good selectivity and stability.3.The 3D ZnO/ITO nanoarrays were prepared by a one-step hydrothermal method,the ZnO/ITO nanoarrays were further modified with aminopropyltriethoxysilane(APTES)and glutaraldehyde(GA)respectively to facilitate the better binding of Sambucus nigra lectin(SNA),then construct electrochemical cytosensor to detect the SA of cancer cells.And the substrate exhibits better mechanical properties than polypyrrole films.In addition,the sensor also shows good stability,high selectivity,wide linear range and high sensitivity.4.A Fe3O4-Mn3(PO4)2@Ni foam composites with 3D network structure were synthesized.Due to the high specific surface area of three-dimensional network structure,which was favorable to immobilize more Fe3O4-Mn3(PO4)2 NPs on foam.Based on the properties of Fe3O4-Mn3(PO4)2 with biomimetic superoxide dismutase,a selective and stable 3D Ni foam cytosensor for superoxide anion(O2·-)shows high detection limit,good selectivity,and provides an important tool in the physiological process of cells.