Design Of Nanopore Single-molecule Detection System Based On ARM

With the rapid development of life science,the research on the phenomenon of life has gone deep into the level of single-molecule and single-cell,In this case,the technology of single-molecule detection has been gradually emerging.Due to the fast and cheap characteristics,the detection technique of nanopore single-molecule stands out in many single-molecule detection technologies.There are three difficulties in the detection of nanopore single-molecule:firstly,it is difficult to produce a nanopore that meets the requirements;secondly,it is too fast of the single-molecule to passes through the nanopore;thirdly the "resistance pulse" has the characteristic of weak,high frequency and high resistance,so it is hard to detect.According to the difficulties of nanopore single-molecule detection,putting forward a scheme of excitation voltage which can change the amplitude and frequency.A complete system of nanopore fabrication process monitoring,the measurement of pore size resistance and the signal detection of single-molecule was designed in this thesis.The system includes the detection device of hardware and software platform,the tests and experiments related were carried out.The main research contents of this thesis are as follows:(1)The theory and the literature of the nanopore single-molecule detection were studied in this thesis,and the parameters of the system were obtained by the experiments;the shortcomings of the electrochemical workstation used in our school are analyzed.A design scheme of nanopore single-molecule detection system based on LabVIEW,USB2.0 and Cortex-M3 was proposed.(2)The hardware circuit of the detection device were designed and produced,to realized the I/V conversion,signal amplification and hardware filtering of the weak,high frequency and high resistance signal.The drive circuit and the USB device were also designed in this thesis,and the system was debugged.(3)The program of detection device was written,including signal acquisition,denoising,filtering,excitation output,USB communication,etc.(4)The USB driver was developed by NI-VISA,and the PC software of the excitation output,waveform display,data storage and alarm were designed under the LabVIEW.The MATLAB script were embedded in the PC software,and the process of etching the nanopore monitoring and the detection of the single-molecule over the hole pulse parameters were written.in the script.(5)A measurement platform was set up and the detection system was calibrated.The average error a'bsolute value of the calibration system is 0.66%,which is in accordance with the design requirements.During the experiment,the resistance of nanopore is 3.89M?.Because of the limited experimental conditions,the process of single-molecule over the nanopore was simulated.The average error absolute value of the pulse falling edge detection is 3.89%,the average error of the pulse rising edge detection is 3.88%,and the average error of the pulse width is 5.94%.