Preparation And Characterization Of Micro/nanofibers Of PCLA For Tissue Engineering

Tissue engineering is an emerging cross-disciplinary,whose purpose is to discover normal and pathological mammalian tissue structure - function relationship with the application of engineering and life science principles and methods, and the develop biological substitutes to restore, maintain or improve an organization's structure and function. Recent years, cell differentiation and tissue regeneration of biological material was also induced to areas of tissue engineering. From the point of view of bionics, the three elements of tissue engineering as follows: artificial extracellular matrix - scaffold materials , cells and the information of growth, in which scaffold materials play a major role. It play not only a specific role to provide structural support, but also a roleof template. It also guide tissue regeneration and control of the structure of tissue. Therefore, the development of tissue engineering and materials science are inseparable , to find a material with good biocompatibility, good biodegradability, a specific shape and a structure of three-dimensional porous scaffold for tissue engineering is a most important thing for tissue engineering.Electrospinning is a technology which spinning jet stream of polymer solution or melt in a strong electric field. It is a simple and effective technology preparing micro/nanofiber materials. By electrospinning a fiber non-woven fibers of small size, large surface area, high porosity, fibers of nanometer diameter can be achieved, as the scaffolds for cells, migration and proliferation can be highly promoted. These features give the electrospinning technique in the field of bio-medical, especially the field of tissue engineering a wide application prospect.PCL-PLA is a new type of multi-block copolymer. As a tissue engineering scaffold material, it has the following characteristics:â‘ With the control the ratio of PCL/PLA, the crystallinity of the copolymer can be controlled, so the degradability can be controlled.â‘¡With the control the ratio of PCL/PLA, mechanical properties of the copolymer can be controlled, we can get a variety of different biodegradable elastic material with different flexibility.â‘¢With the improve of the thermal properties, the materials is conducive to the thermal processing.In this paper, PCL-PLA and the mixture of PCL-PLA/chitosan is electrospun to a series of micro/nanofibres, the following aspects of work are done:â‘ PCL-PLA of different PCL/PLA in ratio is dissolved to different concentrations in chloroform and DMF, an increase in diameter is found with concentration grows, after the first increase the trend is decreasing. With the increase of DMF, the diameter decreases, and so dose the porosity. After electrospun, water absorption enhanced, and the velocity of degradation grows. With the control of the concentration and the ratio of PCL/PLA, the mechanical Properties can be controlled. In the observer training of fibroblasts, we found cells are growing well among the fibers, and cells grow with polarity, which may be quiet useful for certain cells, for example, corneal stromal cells.â‘¡PCL-PLA/chitosan is electrospun in trifluoroacetic acid. After electrospun , water absorption enhanced , and the velocity of degradation grows. Also, in the observer training of fibroblasts, we found cells growing well among the fibers, and also growing with polarity.