Research And Development Of Microfluidic Chip Cell Automatic Printing Control System

In the past few years,automatic cell printing technology based on microfluidic chip has been widely used in the field of cell analysis.However,when ink-jet printing,laser printing,extrusion deposition printing and other printing methods complete the automatic operation,they will also bring some problems,such as high nozzle temperature causing damage to some cell structures or the syringe structure causing cell stacking,and it is not convenient for cell separation and printing,which has a negative impact on the following research.Therefore,in view of the above problems,this paper studies the cell automatic printing system,the specific research is as followsFirst of all,this paper introduces the automatic cell printing equipment,and gives the structure and working principle of the equipment,mainly including the microscope detection unit,cell injection control unit,microfluidic chip motion control unit,measurement and control unit for cell printer.The whole cell printing process is analyzed through the automatic control system.At the mean time,a cell separation and reinjection technique for cell injection was proposed.Then,after the completion of the cell printing equipment,the microfluidic chip field of view used to complete the printing process under the microscope is automatically focused.According to the characteristics of the microscope itself and the requirements of the systems,under the conditions of high efficiency and stability,through the comparison of consumption time,the central window method is selected to complete the selection of the field of view under the microscope.After selecting the window function,according to the analysis of the experimental requirements,the sum of modulus of gray difference function is used as the focus sharpness evaluation function to analyze the performance evaluation of the focusing process.At the same time,through the hybrid extreme point searching algorithm,300 selected images are searched.After 59.82s of searching time,the focus sharpness evaluation function of the selected image at 260?m reaches the extreme value,that is,the value of auto focus point,which completes the automatic focusing process.Finally,the cell printing process is controlled and completed by focusing a clear field of vision.According to the change of printing modes and printing speeds,a comparative experiment is carried out.The movement process of XY-axis microfluidic chip and Z-axis syringe injection process and their parallel movement process were carried out.Through image detection,it is concluded that the microsphere solution printing effect is the best when XY-axis and Z-axis are parallel;At the same time,through the comparison of two groups of different speeds of Z-axis syringe,it is concluded that the printing effect is better when the syringe runs at the speed of 0.0125mm/s.Based on the experimental results,it is concluded that the printing effect is the best when the XY-axis and Z-axis are parallel and the syringe speed is 0.0125mm/s.