Experimental Study On A System For Oocyte Micro-denudation Based On Microdroplet

With the rapid development of life sciences,the micromanipulation of cells has become a frontier research hotspot,and oocyte micro-denudation is one of the crucial operations in assisted reproduction.Most of the existing methods for oocyte denudating are manual operation,with low repeatability,low success rate.And sometimes manual operation may leads to loss of oocytes.Therefor,it is of great significance and value to study oocyte micro-denudation.In this paper,we aims to increase the efficiency and success rate of oocyte denudation,construct a microdroplet preparation system and micro-operation platform,and complete the research of mouse oocyte micro-denudation technology in microdroplet through computer.Firstly,the principle of microdroplet preparation and oil-covering in the dish was analyzed.Then,the scanning and identification of the oocytes in the microdroplets were analyzed,and the principle of the movement of the oocytes in the microneedle was analyzed.The corresponding physical model was established to analyze the relationship between the displacement of oocyte in the microneedle and the speed of the micro pump piston.Secondly,the droplet preparation system was set up for the oocyte denuding and the HMI and the PLC program were programmed for human-computer interaction and motion control.Then according to the previous theoretical analysis,we summed up the main points,selected appropriate motion execution system and microscopic vision system,connected the execution components and drivers of each module correctly,then connected each module to the industrial computer.In the end,the hardware system of oocyte micro-denudation was finished.Thirdly,the conversion relationship between the screen coordinates,platform coordinates and physical coordinates of the oocyte micro-denudation system,and correct the camera declination.According to the three-point circle algorithm to compile the corresponding application program interface,image acquisition interface and image parameter adjustment interface,the various functional modules are integrated together to design human-computer interaction interface.Finally,the volume accuracy,positioning accuracy and ratio of height-diameter of the prepared droplets were analyzed.The mouse oocytes were used for experimental study in prepared droplets.The deep positioning experiments of micro-needle,oocyte scanning and localization experiments,oocyte denuding experiments and oocyte transfer experiments in different droplets were performed respectively,and the results were analyzed.The experimental results show that the oocyte denuding method based on droplets in this paper improved the efficiency and success rate,and completed the oocyte denuding operation within 50~60 seconds.The success rate was increased by 17.3% compared with the artificial operation.