Fabrication Of Three-Dimensional Sensor Coated With Conductive Polymer For Cell Monitoring

Electrochemistry has attracted tremendous interest because of its fast response,high sensitivity and easy manipulation in real-time monitoring of living cells in situ.So far,remarkable progresses have been made in electrochemical monitoring of cells using a wide diversity of electrochemical sensors.In general,one dimensional(1D)electrode(e.g.,single microelectrode or nanoelectrode)can be placed near or inside individual cells to realize monitoring at single cell or subcellular level.Alternatively,cells can be directly adhered or cultured on the surface of two dimensional(2D)electrodes(e.g.,planar electrode or electrode array)for electrochemical detection.However,the cells are cultured on 2D substrates under above circumstances,which fails to reflect the essential features of cells cultured in 3D microenvironment.In view of this,it would be of great importance to construct an integrated platform capable of 3D cell culture and electrochemical sensing simultaneously.However,3D materials equipped with both excellent conductivity and biocompatibility are rarely reported.In order to establish a 3D conductive scaffold,researchers have already developed a series of 3D scaffolds including such as chitosan,polycaprolactone,polyglycolic acid and polydimethylsiloxane(PDMS),to simulate the 3D cellular microenvironment.These scaffolds have been widely investigated in 3D cell culture,proliferation and differentiation,which highly facilitates their applications in a number of areas such as tissue engineering and gene therapy.Nevertheless,most of these 3D scaffolds are made of insulated materials,which greatly restrains their application in electrochemical detection.In this regard,it is expected to provide a versatile approach by endowing 3D insulated culture scaffolds with electrochemical detection performance through conductive material modifications.In view of the research backgrounds and challenges,this paper aims at proposing a versatile strategy to endow 3D insulated culture scaffolds with electrochemical performance while granting their biocompatibility through conductive polymer coating.Herein,we constructed a 3D conductive scaffold with electrochemical performance and biocompatibility by coating conductive polymer on 3D insulated scaffold.Thus,a 3D composite electrochemical sensor with biocompatibility and electrochemical performance was constructed for cell monitoring.The main works of this thesis are summarized as follows.1.We assemble conductive PEDOT film on 3D insulated PDMS scaffold to prepare a3D conductive scaffold,then Pt NPs electrodeposition was further implemented to improve the conductivity and electrochemical performance.The obtained 3D device demonstrated fast response,high sensitivity and low detection limit towards H₂O₂ and was appropriate for long-term cell culture,proliferation with high viability owing to its good biocompatibility.Therefore,cells were cultured on the surface of 3D scaffold,and a promising anti-cancer drug(tetraethylthiuram disulfide together with copper chloride,denoted as DSF-Cu Cl₂)-induced ROS release was monitored in real time for the first time.With this integrated platform,cells were cultured on the surface of 3D scaffold,and a promising anti-cancer drug(tetraethylthiuram disulfide together with copper chloride,denoted as DSF-Cu Cl₂)-induced ROS release was monitored in real time for the first time.2.To further release application of this 3D electrochemical sensor into flexible and stretchable devices,we modified PEDOT with C₂F₆Li NO₄S₂ thus constructed a stretchable3D electrochemical sensor with excellent electrochemical properties.The obtained 3D device demonstrated fast response,high sensitivity and low detection limit towards NO.It is expected to be used in the construction of 3D microenvironment of cells and application in electrochemical detection under mechanical deformation.To sum up,we proposed a versatile strategy to endow 3D insulated culture scaffolds with electrochemical performance while granting their biocompatibility through conductive polymer coating.With this integrated platform,a promising anti-cancer drug DSF-Cu Cl₂-induced ROS release was monitored in real time for the first time.Moreover,we continue to modify this 3D electrochemical sensor with excellent stretchability.Thus,the application prospect of this promising stretchable scaffold in real-time cell monitoring is expanded.