Development Of Multichannel Microfluidic Chip And Its Application In The Detection Of Autoimmune Diseases And Respiratory Viruses

Microfluidic technology has been widely used in in vitro diagnosis,hydrogel preparation,microdroplets,and organ chips,and has currently become a research hotspot for scholars around the world.In this thesis,there are two multi-channel microfluidic chips for in vitro diagnosis designed and developed,which both could realize the simultaneous detection of multiple targets.This thesis was jointly guided by Shenzhen YHLO Biotech Co.,Ltd.and Hunan University of Technology.Based on the scientific research,and jointly guided by both corporate and university,two kinds of microfluidic chips for immune disease detection and respiratory pathogen molecular detection were researched and developed to meet the demand of the corporate for new product development.The microfluidic chip provides an appropriate pre-research foundation for the development of commercial microfluidic chips.The main research contents of the thesis are as follows:1.By optimizing the process design,a multi-channel microfluidic chip preparation platform with multi-channel and multi-chamber for simultaneous detection of multi-target was established.In terms of different experimental steps and reaction conditions,there are two types of multi-channel microfluidic chips are designed and fabricated for immunoassay and molecular detection respectively.In order to research the optimal processing parameters in the fabrication of the chips,both processing power and speed were promoted,and the fabricated chips were characterized.2.The prepared immunofluorescence detection chip was used to detect RNP antibody and Sm D1 antibody which is the target of autoimmune disease.On the microfluidic platform,the single detection of single-channel single-marker to the simultaneous detection of dual-channel dual-marker is realized.The detection ranges for RNP antibody and Sm D1 antibody was 9.6-444.0 AU/m L and 12.5-424.8AU/m L,respectively,the RSD was 4.4%and 3.5%,and the detection limits were 5 AU/m L and 6.25 AU/m L,respectively.The detection results have good reproducibility and specificity which means the chips can be applied to the rapid and convenient diagnosis of autoimmune diseases.3.Based on the principle of loop-mediated isothermal amplification technology,the prepared molecular detection chip is simultaneously used for the visual detection of SARS-Co V-2,Influenza A virus and Influenza B virus in respiratory viruses.Taking the SARS-Co V-2 pseudovirus,Influenza A plasmid,and Influenza B plasmid as test samples respectively,the reaction system was driven by centrifugal force,and the liquid was evenly divided into each reaction structure of the chip through the liquid separation structure,the reaction solution is finally mixed evenly with the primers stored in the chamber,check the reaction result after 65℃reaction for 30 min.The experimental results show that the detection limits of the self-made chips for the SARS-Co V-2,Influenza A and Influenza B virus were 1.6×10~2copies/μL,1.1×10~3copies/μL and 5.5×10~3copies/μL,respectively,and there is no cross reaction between the three pathogen detection systems.The reactivity and specificity are good,which can realize the chips can be used to visual and simultaneous detection for SARS-Co V-2,Influenza A and Influenza B virus.