Development Of A Single-cell Automatic Separation Device

Single-cell analysis is of great significance for drug screening,stem cell research,cancer diagnosis and treatment,etc.As a precondition for single-cell analysis,cell separation has an important influence on single-cell analysis.Therefore,the development of a single-cell separation device has vital importance.With the deepening of related research,traditional single-cell separation technologies and devices have been unable to meet the needs of modern cell analysis.The separation efficiency of single-cell separation devices based on microfluidic technology is greatly affected by the cell sample concentration and cell solution flow rate.Aiming at the above problems,this thesis develops a single-cell automatic separation device.The specific research work is as follows:Device structure design.In order to quickly separate the single-cell from the solution and place them in the designated microcavity container,the device is divided into four modules:liquid feeding,detection,separation and deployment,and the overall structure of the device is designed in combination with the supporting fixtures of each module.Taking the flow channel structure design as the starting point for detailed analysis,based on the principle of microfluid mechanics and combined with the inertial focus simulation results of common flow channels,the snake-shaped inlet flow channel is designed and the flow channel size is given,which reduces the multi-cell adhesion;In order to improve single-cell detection and separation efficiency,a double " Y"-shaped flow channel and cell flow control method are designed to improve the accuracy of single-cell separation;In view of the problem that the existing single-cell deployment flow channel is difficult to quickly form droplets,the " The T"-shaped spurt channel and the cell flow control method increase the spurt speed of single-cell droplets.Device detection and control system design.Firstly,the Jetson TX2 embedded system is selected to process the image according to the performance requirements of the device.The image acquisition system is designed by testing the influence of the light source on the imaging effect of the camera,and the detection algorithm is given.Secondly,based on JetsonTX2 embedded system and STM32 controller.the device detection and control system are designed to meet the real-time control requirements of multiple devices.Through theoretical analysis and simulation,the influence of the device's own characteristics on the control accuracy is evaluated,and a solution is given to the non-negligible hysteresis problem of the air drive.Finally,optimize the parallel part of the o'verall control process to further improve the operating efficiency of the device.Device testing.Firstly,build the device and prepare the reagents needed for the test.Secondly,the corresponding relationship between the actual flow rate and the theoretical flow rate in the flow channel is obtained through experiments,so as to test the influence of different flow rates and different solution concentrations on the operating efficiency of the device.Finally,polystyrene microspheres are used to simulate cells to test the efficiency of this device in separating a single microsphere from the microsphere solution and placing it in a single microcavity of a 96-well plate,The results show that the separation speed of the microspheres is 1 per second,and the accuracy rate is 92%.The device designed in this thesis can separate single-cell in the cell solution into the designated microcavity,which is helpful for subsequent single-cell analysis and has high application value.