Dual-Path Fluorescence Detection System Based On Microfluidic Chip

With the rapid development of science and technology,the research on the combination of microfluidic technology and fluorescence detection method has been highly valued.The single wavelength fluorescence detection method for complex cells is limited,which makes the dual-color fluorescence labeling method widely used in various fields.However,commercial fluorescence detection devices are expensive and complex operation,which limits its use to a certain extent.In view of the existing problems,this paper designs the dual-path fluorescence detection system based on microfluidic chip.The detection principle of the system uses laser induced fluorescence to detect the fluorescence of chlorophyll in microalgae and fluorescent particles.This system uses microfluidic chip as the testing platform,testing samples through the side light source irradiation and emits two fluorescence,received by photodetectors located at the top and below of the detection area,so as to realize fluorescence detection and counting.of two kinds of fluorescent particles or different cell.The detection system is mainly composed of microfluidic chip,light source module,dual-path fluorescence detection module,signal acquisition and processing module,power module,ARM control module and mechanical mechanism.The light source module uses a suitable optical path structure to provide an exciting light path for the dual-path fluorescence detection module.The rectangular slit in the center of slit can reduce the background noise and ensure the consistency of the two fluorescent signals,which improves the signal-to-noise ratio and the sensitivity of the detection system.The signal acquisition and processing module performs filtering,amplification and analog-to-digital conversion,and simulates signals to simulate the filter amplifying circuit instead of the actual fluorescence signals,so as to ensure that the hardware can work well.The power supply module provides the working voltage for the whole system to ensure each module can work well.The program design of ARM control module,driving module and Qt display module is completed,and the miniaturization of the detection system is also realized.The mechanism module is used to assemble each module to complete the integration of the detection system.In order to verify the performance of the detection system,we test the performance of each module and module integration,and then detect fluorescence intensity of the three typical microalgae and fluorescent particles,compared to the result of the commercial flow cytometry,which verifies the accuracy of the system.Compared with common fluorescence detection equipment,the dual-path fluorescence detection system proposed in this paper has the characteristics of less consumption,faster detection speed,portable and miniaturized.