Design And Experimental Research Of Application-Oriented Microenergy Minimally Invasive Oocyte Piezoelectric Microinjector

Since entering the 21st century,the field of life science has ushered in a climax of development,and various micromanipulation techniques have emerged endlessly.The core technology is the most widely used ultrasound microinjection technology.This technology has a place in various micromanipulation fields,such as cloning technology,assisted reproduction technology and transgenic technology.The traditional microinjection technique was to directly pierce the zona pellucida and the cell membrane through physical puncture,which caused great damage to the cells and was not conducive to the subsequent culture of the cells.After intensive research by a large number of scholars,the introduction of ultrasound technology into microinjection technology has largely solved the problem of large deformation of injected cells.But the lateral vibration caused by ultrasound technology is another difficult problem for cell damage.Therefore,developing a micro-syringe with less lateral vibration is of great significance to the current micro-manipulation field.In view of the current problems in the field of microinjection,the subject proposes a microinjector based on a triangular flexible mechanism.During the microinjection process,the microinjector could greatly reduce the lateral vibration of the needle tip and reduce the damage to the cells.On the other hand,it could ensure that cells successfully completed their destruction under conditions of micro-deformation and micro-trauma.Membrane technology;at the same time,the structure of the syringe can perfectly match the structure of current microscope imaging systems and commercial microinjection needles.The main research contents are as follows:First,the development of the current microinjection technology is briefly described,and the current development direction of the microinjection technology is to minimize the lateral vibration of the ruptured needle tip as much as possible.Then,combined with the ultrasonic technology,the corresponding ultrasonic membrane breaking theory is given.Secondly,the physical characteristics of micro-injection needles currently on the market are analyzed,and then the micro-injection needles are analyzed and studied according to the differential equations of deflection and rotation angle in material mechanics.Then use the superposition principle to fit the vibration state of the tip.Finally,the influencing factors of the lateral vibration of the needle tip were determined,and the best parameters of these factors were obtained.Third,design a micro-syringe with a flexible mechanism.Due to the vibration characteristics of piezoelectric ceramics,the vibration at the output end includes not only axial vibration but also lateral vibration,which is amplified by the cantilever-shaped injection needle.The lateral vibration of the tip will be greater,which will cause greater damage to the cells.In this project,a triangular flexible mechanism was introduced into a piezoelectric drive source and lateral vibration was reduced from the vibration source.Based on the AWTAR theory,most parameters of the triangular flexible mechanism were optimized with the maximum resolution of the piezoelectric drive source.The parameter settings in microinjection were optimized by the Euler Bernoulli beam equation.In addition,through ANSYS simulation,the optimal clamping distance of the microneedle was optimized to further ensure the stability of the tip vibration.Fourth,based on previous theoretical research,corresponding experimental equipment is designed and processed,an oocyte microsurgery system platform is established,and oocyte microinjection experiments are performed.The piezoelectric ultrasonic microinjector based on the triangular flexible mechanism is analyzed for the lateral and axial amplitudes of the needle tip under microscopic observation,and its practicality is obtained.A mouse oocyte injection experiment is performed.By comparing multiple sets of data,it can be concluded that when the signal generator outputs a vibration frequency of 25KHz and a vibration amplitude of 5V,the microinjector is in an optimal injection state.Finally,the oocyte damage is observed in the experiment,and the cause of the damage is analyzed,which provided a certain theoretical basis for future micro injection technology.