Development Of Tissue Engineering Scaffolds Based On Near-field Melt Electrostatic Direct Writing Technology

Tissue engineering is a new discipline that is applied to the principles and technologies about engineering and Life Sciences,and is developed to restore,maintain or improve biological functions of tissues.How to construct a tissue engineering scaffold with the structure and function of the biomimetic natural extracellular matrix has always been a hot topic in the research of tissue engineering and regenerative medicine.Unlike traditional spinning,electrospinning is a processing method for preparing charged polymer solution or melt in the electrostatic field to prepare polymer nanofibers.The nanofiber scaffolds prepared by this technique can better simulate the structural characteristics of the natural extracellular matrix.The near-field direct-writing melt electrostatic technique is different from the traditional electrostatic spinning technology.It is a more low-voltage,safer and more environmentally friendly spinning method.The fiber preparing by the technique has the characteristics with controllable deposition.Besides,no solvent is needed in the preparation process.The materials obtained are innocuous,which greatly promotes the application of the technology in micro nano processing,tissue engineering,clinical medicine and other fields.Meanwhile,this technology also improves the utilization efficiency of polymers.This article mainly consists of three parts,First,I have summarized the related theories about the tissue engineering scaffold,the development process of the near-field electrospinning technology and its application.The second,I tried to find the best spinning technology of near-field direct-writing melt electrostatic technique and prepare the different morphologies of polycaprolactone scaffold.The three is to modify the polycaprolactone scaffold and test its related properties.First,this paper introduces the theory about biological tissue engineering scaffold and discusses the research background of near-field direct-writing melt electrostatic technique,meanwhile,it also states the related theory of near-field direct-writing melt electrostatic technique;in-depth study of the research results,the electrostatic direct writing technology development trend and existing problems.The research achievements,development trend and existing problems of electrostatic direct writing technology are also studied in this paper.I prepared different morphologies of polycaprolactone scaffold according to the optimum process parameters.Second,this study designed the orthogonal experiment of four factors and four levels,and obtained the optimum process parameters according to the four main factors affecting the spinning effect.The thickness and contact angle of the stent were measured and the morphology of all the scaffolds was observed by TM3030 electron microscope.Third,the polycaprolactone scaffold prepared by the near field melt electrostatic direct writing technique was modified and studied its properties.The polycaprolactone scaffold was impregnated with different concentration of chitosan solution,then test the antibacterial properties and find the optimum concentration.The polycaprolactone scaffolds with different morphologies were modified by the optimum concentration of chitosan solution,then studied their related properties.the polycaprolactone scaffolds with the same morphology are modified by different polymers,and studied the related properties of the scaffolds.Finally,I have summarized the experimental situation,combined with the predecessors' exploration,consulted a large number of relevant document and planning the next step.