Construction Of Functional Elastic Artificial Blood Vessels And Simulation Of Pulse Fluid

The components and microenvironment of blood vessels in human body are very complex,which results in the great difficulties of constructing the vascular model in vitro and imitating the microenvironment.At present,there are many methods for the preparation of artificial blood vessels,and the effects of dynamic fluid on the function and morphology of vascular endothelial cells have been extensively investigated.However,three-dimensional artificial blood vessels,which have dynamic mechanical elasticity and can withstand shear force,periodic tensile action and have similar function and shape as clinical vessels,have not been completely imitated in vitro.The construction of three-dimensional artificial blood vessels can assist researchers to quantitatively study the growth and reproduction of vascular endothelial cells under the action of shear force and periodic stretch,as well as the biological characteristics of the cells under stress.This can not only present the real blood vessels and their microenvironment in human body in vitro,but also provide a practical research platform for the pathological exploration and clinical treatment of cardiovascular diseases.Cardiovascular disease seriously threatens human health and life.Accordingly,more attention has been attached to the exploration of vascular endothelial function.What’s more,with the development of hydrodynamics,the mechanism of fluid acting on vascular endothelial cells has been gradually revealed.Under the condition of pathological fluid,the effect of fluid on the vascular endothelium will change.Unfortunately,in this process,it is unclear which kind of effect endothelial cell function will be affected.Although devices capable of generating pulsed fluids,in recent years,have been developed and applied to in vitro experimental studies.However,it is still remain enormously challenging for cell culture and accurate control of pulse fluid flow in the device.In this context,this paper mainly does three aspects of work to explore the above issues.First,the preparation and mechanical properties of PDMS elastic artificial blood vessel.3D printing technique and perfusion model method was adopted,which made three-dimensional PDMS elastic artificial blood vessel closer to the three-dimensional spatial structure of human blood vessel in space.Furthermore,the structure and morphology of the inner surface of the elastic artificial blood vessel were observed by field emission scanning electron microscopy;The Young modulus of PDMS hollow tube samples prepared under two different curing conditions was measured and analyzed by nano indentation instrument.And the PDMS elastic artificial blood vessel,which is closer to the Young modulus of the elastic fiber in the human blood vessel,was chosen as the experimental research object in this paper.Second,the simulation of aortic flow curve.A device built in vitro and capable of accurately controlling the waveform of pulsed fluid flow is realized by modifying the program command of the solenoid valve control system in the pulsed fluid device.In the simulation experiment of dynamic fluid,the human ascending aorta blood flow curve was took as the research object in this paper,and the waveform of the curve in vitro was realized using the pulse fluid device.In addition,COMSOL Multiphysics 5.4 software is used to simulate the flow field and stress field of pulse fluid in the PDMS functional elastic artificial blood vessel,which makes the flow field and stress field of the artificial vessel more vividly.Third,the biofunctionalization of PDMS elastic artificial blood vessel.The human umbilical vein endothelial cells(HUVECs)were implanted into the artificial vessels by modifying the inner surface of the artificial vessels,and the endothelial cells were cultured in static state.Then,the artificial blood vessel was connected into the digital pulse system device.Based on the flow curve of the ascending aorta,the pulse fluid generated by the pulse system device was used to explore the changes of the endothelial cells of the artificial blood vessel.