Control Of Flow Field In Droplet And Its Application In High-resolution Imaging Of Zebrafish

Zebrafish has the characteristics of optical transparency,genetic maneuverability,and human gene homology,so it is very suitable for molecular genetic testing and drug screening.Zebrafish's exercise ability can usually be used to reflect its brain dysfunction,impaired motor function and sensitivity to environmental changes.Researchers have found that the lack of Lipin1 protein expression in humans can cause muscle weakness in adults and accompanied by peripheral nerve diseases,and zebrafish can use the loss of Lipin1 to simulate the corresponding neuromuscular performance.At present,in the study of the sports performance of the zebrafish model,researchers often use the touch and observation method.For fluorescence imaging at the cellular scale,zebrafish need to be anesthetized and fixed before shooting.The problems with traditional research methods are: a.The touch observation method is too simple and has large errors;b.Anesthesia fixation will affect the normal movement of zebrafish.Therefore,an accurate and effective method is needed to evaluate the impact of nerve damage on zebrafish's motor ability.While maintaining the dynamic environmental conditions of zebrafish,it needs to complete its high-resolution fluorescence and brightfield imaging.This article has done the following work on the research of zebrafish's sports behavior ability and its biological mechanism:1.According to the swimming characteristics of zebrafish,a miniature swimming pool type device is designed and prepared.In a circular structure with a diameter of 12 mm,wildtype zebrafish juveniles of 3-4 mm are constantly moving to find a comfortable foothold.The study found that wild-type zebrafish swim at high speed under non-contact conditions,indicating that the device can effectively distinguish zebrafish with different sports abilities.2.In order to construct dynamic environmental conditions while restricting zebrafish movement,this study constructed a droplet flow field system.The system introduces a flow field into the droplets on the glass substrate through the vibration of an external rotor.By changing the frequency and amplitude of the percussion vibration,it produces different flow field phenotypes(including one-circle,two-circle,and four-circle.).Furthermore,by calculating the moment of the object in the flow field,this study inferred that there are two equilibrium points in the four-circular flow.The position distribution of the zebrafish between the two equilibrium points has been verified by experiments as an important parameter for evaluating its athletic ability.At the same time,under the restriction of the four circulations and droplets,the device can realize high-resolution fluorescence imaging of zebrafish,which provides an important technical basis for studying the cell behavior of zebrafish in vivo in a dynamic environment.In summary,in view of the problems and practical needs of zebrafish movement behavior research,this article uses 3D printing technology,combined with controllable droplet flow field,while restricting zebrafish movement,a dynamic flow field is generated in the environment and realized High-resolution imaging.