Design And Implementation Of Coagulation Detection System Based On QCM

The progress of society has also promoted the development of medical detection technology,which has made the research on hemostasis and thrombosis more and more in-depth,and also promoted the research and use of detection instruments.Quartz Crystal Microbalance is a new type of piezoelectric sensor,which is widely used in biomedicine,environmental monitoring and electrochemical analysis because of its advantages of small size,low cost,real-time measurement and high sensitivity.Most of the coagulation testing equipment which currently used are large-scale coagulation analyzers used in hospitals.There is still a certain gap in the market for miniaturized and portable coagulation testing equipment,and portable equipment have a greater social demand for home testing.Based on the advantages of the above-mentioned QCM and the background of lack small coagulation testing equipment in the current society,a simple coagulation testing system for obtaining coagulation-related clinical indicators is designed,which provides a technical reserve for the further development of household coagulation testing instruments.The main contents of the article are as follows:1.Thesis starts with the mechanism of coagulation,briefly introduces the mechanism of coagulation reaction,the reaction routes of both internal and external coagulation pathways and the coagulation factors involved.Then,based on the crystal structure and properties of quartz,the detection model and working principle of QCM are deeply studied,and the gas phase model,electrical BVD model and liquid phase response mode of QCM were studied.On this basis,the current main QCM signal measurement methods were studied,combined with the liquid phase response model and the oscillatory circuit method was selected as the signal acquisition method of the coagulation test system,and the design route and implementation method of the system were given.2.Design a test system for blood coagulation detection.QCM is used as the sensor probe and the Pierce double-inverter oscillator circuit was used to obtain the resonant frequency.The Field Programmable Gate Array(FPGA)was used as the core chip of the hardware system of the lower computer,and the communication interface is USB Type-c completes the design,pattern making and welding of peripheral circuits around the core chip.The output QCM signal is measured by the equal-precision measurement method,and the control program for the frequency signal measurement and transmission of the lower computer is written.Then,the upper computer system framework is built with Python,which realizes the communication with the lower computer and the display,data processing and visualization of the transmitted real-time frequency signal;at the same time,the data storage and playback are realized,and the overall construction of the coagulation test system is completed.3.The coagulation test system constructed by the text was used and the coagulation experiment was designed in combination with medical theory.Finally,the test experiment of the endogenous coagulation pathway was carried out with this system,and the coagulation reaction stage corresponding to the frequency curve was studied,and then the coagulation change of QCM was used.The relevant clinical indicators were obtained from the curve and compared with the commercial coagulation analytical instrument.The improvement and deficiency of the test system are analyzed through the experimental results...