Design Of The Microfluidics Suitable For The Study On Cytotoxicity Of Silver Molybdate Nanowires

With the development of integrated circuits and microelectronics,medical electronic equipment has become more miniaturized and integrated.In recent years,the research of cell analysis based on microfluidic chip has gradually matured.Microfluidic chips are highly integrated and widely used in cell culture,cell sorting and identification,biochemical analysis and cancer drug research.At present,the conventional clinical treatment of cancer still faces some problems,such as low curative effect,obvious side effects and poor targeting.Nanomaterials show broad application prospects in cancer diagnosis and treatment because of their unique optical and mechanical properties,good biocompatibility and biodegradability.Silver molybdate nanowires have certain antibacterial and anticancer effects,which can further explore the feasibility and cytotoxicity mechanism of silver molybdate nanowires in cancer treatment.However,the current researches on the application of nanomaterials in cancer diagnosis and treatment are mostly based on population cells,ignoring the heterogeneity among cells,and unable to monitor the morphological changes and metabolic changes of cells in response to external stimuli in real time.At present,there are few biochips with poor pertinence,which can not meet the needs of scientific research and clinical application of cancer diagnosis and treatment at the single cell level.In this paper,the selective specificity of cytotoxicity of silver molybdate nanowires was studied exploratively,and a microfluidic system integrating single cell capture function and temperature monitoring function was designed.Four key elements of the microfluidic system,i.e.electrostatic tweezers unit,microfluidic channel,thermocouple array and Si3N4 suspended platform,were prepared and characterized respectively.In order to successfully carry out the experimental study on cytotoxicity at single cell level in microfluidic system,we first identified the cancer site with the biggest difference in cytotoxicity of silver molybdate nanowires and the best concentration.In this thesis,silver molybdate nanowires were used to study the cytotoxicity of cancer cells and normal cells in human stomach and liver at the cell community level.This kind of silver molybdate nanowires has greater cytotoxicity to gastric mucosa cells than gastric cancer cells,and has more obvious effect on inducing apoptosis in gastric mucosa cells,so it is not suitable for cancer treatment in stomach The cytotoxicity to liver cancer cells is greater than that of normal liver cells,and it has selectivity.The best concentration range with obvious difference in cytotoxicity in liver region is 2.5-12.5?g/ml,which provides basic reference data for future research at single cell level.The related applications of microfluidic single cell capture technology and cell metabolism detection technology were investigated,and a microfluidic chip integrating single cell capture function and temperature monitoring function was designed by using microelectronics and micro-nano processing technology Build a constant temperature system to reduce the thermal noise of single cell temperature measurement,design multi-channel gating and real-time temperature measurement control software,and plan different functional modules;Finally,the experimental scheme of exploring the cytotoxicity of silver molybdate nanowires at the single cell level by using the designed microfluidic system is designed,which lays a foundation for studying the mechanism of cytotoxicity of silver molybdate nanowires at the single cell level.Completed the preparation and characterization of the key units of the designed microfluidic system.We have prepared Ti-Au metal strip electrostatic tweezers unit modules with double-ring structure,triple-ring structure,double-ring structure and dielectrophoresis effective combination The microfluidic channel is designed and prepared and bonded with the electrostatic tweezers unit to complete the single cell capture function.A thin film thermocouple array unit composed of Cr and Pd was prepared,and a silicon nitride suspended platform was prepared by etching Si3N4(400 nm)-Si(410 ?m)-Si3N4(400 nm)material,which provided technical support for cell metabolism detection,reduced the heat consumption of the substrate during the contact between the chip and the object to be measured,and effectively improved the temperature measurement accuracy.Through this part,the operation flow of each process and the specific parameters in chip preparation are explored,which provides reliable process steps and parameters for the subsequent integration of multifunctional microfluidic chips and improves the success rate of device preparation.In this paper,based on the purpose of exploring the cytotoxicity of molybdate nanowires at the single cell level,a microfluidic system integrating single cell capture function and temperature monitoring function was designed,and the preparation of multiple functional areas of microfluidic chip was completed.This not only lays a foundation for the study of cytotoxicity of silver molybdate nanowires at single cell level,but also promotes the development of cancer treatment technology,and provides a new technical scheme for single cell capture and cell metabolism detection,and provides a multifunctional platform for single cell analysis.