Electrochemical Detection Of ROS Changes In Cancer Cells And Its Effect On The Synthesis Of Silver Nanoclusters

ROS(reactive oxygen species)is a series of reactive oxygen species produced by cells during metabolism.As an intracellular environmental regulator,it plays a crucial role in cell injury,synthesis of substances,and apoptosis.When a large number of ROS is in the cells,it will destroy the internal environment of the cells.Therefore,the detection of intracellular ROS changes and the dynamic actions of cells are scientifically valuable for the study of redox reactions at the cellular level and the development of cancer treatments.Boron-doped nanocrystalline diamond(BNCD)shows unique and superior biocompatibility,high transparency and chemical as well as electrochemical stability.The BNCD electrode can provide a wide potential window ranging from-2.0 V to +2.0 V with low background current and high corrosion resistance.Therefore,BNCD as a very attractive electrode material can be well used as electrochemical bioassay detection.In this dissertation,in situ synthesis of silver nanoclusters was used to realize fluorescence imaging of tumor cells.Boron-doped diamond microelectrode arrays were designed and used as electrochemical detection tools to detect the changes of ROS content during in-situ synthesis.The main research content is as follows:1.Silver nanoclusters were synthesized in situ and fluorescence imaging of the cells was achieved.The prepared complex [Ag(GSH)]+ was incubated with tumor cells at a concentration of 20 ?M for 24 hours,and observed by confocal fluorescence microscopy.It shows good and stability fluorescence imaging of cells with good biocompatibility.In situ synthesis of silver nanoclusters can be used as a good bioluminescent imaging probe for cells.2.16-channel boron-doped diamond microelectrode arrays(BNCD-MEAs)were designed and fabricated.20 ?m boron-doped diamond working electrodes were fabricated by chemical vapor deposition technique and integrated into an array electrode chip.Through electrochemical characterization test,the 16-channel electrode arrays have very good electrochemical properties and can be used as hydrogen peroxide sensors,which has high sensitivity and strong anti-interference ability,and provides a possibility for electrochemical bioassay.3.The intracellular ROS content and changes were detected using kits and electrochemical methods.Ascorbic acid was added to stimulate cells to release hydrogen peroxide,and boron-doped diamond microelectrode arrays were used as hydrogen peroxide sensors to detect the release of oxygen.By comparing with normal cells,the ROS content tumor cells shows higher level.However,a certain amount of ROS is consumed after the silver nanoclusters generated in tumor cells.Microelectrode arrays were also used to try to work on single cell detection,and good signal was obtained,which laid the foundation for future single cell research.