Automatic Fetal Nucleated Red Blood Cells Slide Processing System Development

Fetal nucleated red blood cells have the complete DNA sequence of the fetus and are an important object of analysis for the diagnosis of genetic diseases in non-invasive prenatal testing.At present,there are still problems in the separation and detection of fetal nucleated red blood cells,such as high sample loss rate,complicated operation procedure,high reagent usage and lack of automation of the process.In response to these problems,this thesis designs and develops a fully automated fetal nucleated erythrocyte slide processing system,using a microfluidic chip as the reaction core,to fully automate the capture and fluorescence in situ hybridization of fetal nucleated erythrocyte samples.This thesis focuses on the following parts of the research work:（1）After analyzing the technical shortcomings of existing methods for fetal nucleated erythrocyte isolation and detection,we propose a fully automated microfluidic chip for fetal nucleated erythrocyte capture and fluorescence in situ hybridization experiments,and carry out theoretical validation and preliminary experimental verification of this idea.（2）The design of a fully automated fetal nucleated erythrocyte slide processing system is proposed.The system includes a core control module,a fetal nucleated red blood cell capture module,a precision temperature control module,a micro-reagent control module,etc.The fluorescence in situ hybridization process is also optimized.（3）Conduct practical tests on the above four core modules of this designed system,and carry out experimental verification of the optimized fluorescence in situ hybridization experimental flow.（4）Complete the design and assembly of each module,and carry out testing and analysis of the overall system,i.e.analysis and optimization of the fetal nucleated red blood cell capture and detection results,as well as testing and analysis of the system for electromagnetic compatibility.The results of the fully automated fetal nucleated erythrocyte slide processing system show that the system can successfully automate the capture and fluorescence in situ hybridization of fetal nucleated erythrocytes based on the microfluidic chip;the microfluidic chip has a high retention rate of fetal nucleated erythrocyte samples and uses a few microliters of reagents,which saves a lot of reagents;the complete detection time of the system is within 5 hours,which greatly reduces the current fetal nucleated erythrocyte capture and detection time;nucleated erythrocyte captures and detection time,effectively increasing the efficiency of the assay;the system can process 16 samples simultaneously,resulting in higher test throughput.The system can handle 16 samples at the same time and the throughput of the assay is high;therefore,the system can fully achieve the expected purpose of the selected topic and all experimental indicators meet its design objectives.This system has achieved the expected purpose,the experimental indicators have met the design purpose and satisfied the requirements of the professional master’s thesis.