| With the rapid development, tissue engineering, which is an interdisciplinary subject built on the basis of biology, cytology, materialogy, life science, is playing an important role in the biological realm. It solve the problem of autograft, and mechanical grafts, taking gospel to numerous patients. There are three elements in tissue engineering including seed cells, biological materials and growth factor, among which biological materials providing growth space and support for the seed cells. Biomedical materials can be divided into several categories, such as natural materials, high polymer composition materials, inorganic ceramic materials, composite materials and so on. But with the development of histology, a single material can not meet the demand of tissue engineering that makes us had to choose different materials to mixed use according to advantages and shortages of materials and different requirement of tissue engineering. There should be pore structures and connectivity in the materials of tissue engineering. The pore structures seriously affect the situation of cells growth that leads the invention of the scaffold materials of tissue engineering to become a hot point of research.Elctrospinning is a method of preparing high porosity scaffold materials, the basic principle of elctrospinning is Taylor cone principle, namely the polymer melts or liquid overcome the surface tension and form very fine filaments under the high voltage. This method is simple, and almost can be used for all kinds of materials. The equipment of elctrospinning is easy to operate, the fiber prepared by electrospinning have controllable diameter, high porosity, big specific surface area, and the 3D space of the fiber is good for cell growthing. Based on these visible features, electrospinning in the filed of tissue engineering will have great development and good prospects.This paper use tissue engineering as a technical guidance and use electrostatic spinning as the method. Composite nanofibers of PLA/modified HA are made by PLA, HA, polyethylene glycol, polyvinyl alcohol and stearic acid. And at last, the capability of the new materials is studied in this paper.The major contents of the work in the process of synthesis of PLA/modified HA are:1. Made the calcium nitrate and ammonium di-hydrogen phosphate as rough material on the home page, preparationed hydroxylapatite by chemical solution coprecipita- tion,and modifined with polyethylene glyzol,polyvinyl alcohol, stearic acid .Through the particle size analysis,SEM,IR,XRD to inspect the size of the material, coating appearance,functional group,crystalling form and analied each them.Preparationed the nanophase hydroxyapatite had good coating appearance,and screenedthe best modifier which matching the HA.2. Chose TCM and DMF for mix solvent of spinning solution . and through surface tension and conductivity of mix solvent and the surface appearance of fiber to adjust the matching of them .Chose the best matching DMF/TCM=3/7.and then research the influence of voltage , receiving distance, spinning solution concentration on appearance of fiber . Through a series of experiments determine the best voltage , receiving distance and concentration for prepare surface fiber . All of these above blaze the trail for prepare PLA/n-HA composite material .3. We prepare Composite nanofibers of PLA/modified HA according to the best volt of morphology of fibers , the receiving distance and concentration,and characterize it.we can observe the modified fiber has uniform diameter,smooth surface,good feature by SEM and TEM.And HA is well-distributed in the fiber.HA keep its crystal in the fiber.According to a serials test of fiber stretch,un-modified fiber seriously affect the mechanical property of the fiber for HA's agglomeration.The mechanical property of the fibe has to do with its surface.The contact angle experiment indicates the hydrophilicity of fiber is improved with addition of HA that makes Composite nanofibers of PLA/modified HA used more and more widely.The tested date of Composite nanofibers of PLA/modified HA shows it has high level porosity and meets the requirement of tissue engineering.4. PLA/PEG-HA modified fiber scaffold, which own the optimal performance, is used in vitro cell culture experiments. We culture the liver cell of the rabbit, which is selected as seed cell, in vitro in 2-3 days, then do fluorescent staining and view its cell growth in the laser confocal microsopy. According to microscope photographs,the cell can grow well at all levels on the scaffold. It indicates that the PLLA/PEG-HA have cell affinity and can guide cell growth.In summary, fabricate PLLA/HA modified fiber scaffolds in the electrospinning method, is a simple and effective method. Among them, modification of HA to prevent its aggregation in the fiber, changing the fiber morphology and properties, and promote their wider application in tissue engineering. All in all ,to prepare PLLA/A modified fiber scaffolds by electrospinning process is a simple and effective method.
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