Research On FISH Detection Based On Microfluidic Chip And Its Automatic Scanning System

Fluorescence in situ hybridization(FISH)is an important molecular biological detection method,which has important clinical significance in screening,diagnosis,medication guidance and prognosis of various diseases.By analyzing the principle and advantages of FISH technology and the development status at home and abroad,this paper illustrates the importance of automated FISH detection technology,discusses the problems of current automated FISH detection technology,and then proposes the research content of this topic.This topic aims at automated FISH testing,and uses FISH technology as a starting point in the diagnosis of leukemia.A series of studies have been carried out on sample processing,hybridization staining,and fully automatic fluorescence imaging during FISH detection.The main research work of this subject is as follows:Firstly,the morphological characteristics of blood cells in whole blood were analyzed.A microfluidic chip based on size separation method was designed for blood sample processing in FISH detection.A simple semi-automatic experimental device was built with embedded technology design.The sample injection and hybrid dyeing on the chip were semi-automatically controlled;blood sample processing experiments and FISH staining experiments were carried out on the basis of the chip and the simple experimental device,which proved the feasibility of the design of the subject.Secondly,this thesis studies the imaging principle of fluorescence microscopy,upgrades the ordinary biological microscope,and replaces the traditional single-pass filter set by using a high-performance three-channel filter set,and guarantees on the basis of no increase in cost.Excellent image quality and improved system scanning speed;the microscope has basic automation capability through self-designed electric stage and electric focusing mechanism;combined with embedded related technology,a microscope controller is designed and The optical imaging performance,mechanical properties,and positioning performance of the microscope were tested and analyzed.Finally,this thesis studies the autofocus algorithm of fluorescence microscope.The practical effect of several classical focus evaluation functions on fluorescence images is analyzed by using MATLAB software.According to the characteristics of FISH images,a dynamic window planning algorithm is proposed.The autofocus speed is improved;the traditional hill-climbing search algorithm is improved,a new decision factor is added in the search process,and the problem that the traditional hill-climbing search algorithm is easy to fall into the local extremum is solved,and the curve is combined after the rough focus searched by the mountain climber.The fitting method calculates the precise focus position and improves the focusing speed and focusing accuracy of the system.This topic applies microfluidic technology,automatic control technology and autofocus technology to all aspects of FISH detection,which simplifies the FISH detection process,improves the automation degree and detection efficiency of FISH detection,and has certain practical application value.