Atmospheric Pressure Plasma Jet Treatment And In Vitro Evaluations On Braided Biodegradable Nerve Regeneration Conduits

Nervous system is crucial to the feeling, reacting and thinking of human being. As sports traumas and iatrogenic damages occur in peripheral nerves, the repair, regeneration and function recovery of peripheral nerves has long been one of the most concerned key problems in neural science field. Nowadays, lots of studies focus on nerve conduits made of biodegradable materials. Having been proved recent years, this kind of conduits can replace the role of autografting and allografting to become one of the most effective nerve repairing means. The conduits can promote nerve regeneration, speed nerve growth, wholly recover nerve functions and have the most favorable industrialization prospects. Among these conduits, braided biodegradable poly(glycolide-co-L-lactide) (PGLA) nerve regeneration conduit has the leading technique nationwide and an advanced one worldwide. With a stable structure, independent intellectual property rights, and with good healing effects in in vivo assays, the nerve conduit has applied National Invention Patent.In order to further enhance the surface properties and to promote the speed and quality of nerve regeneration, the auther introduced atmospheric pressure low temperature plasma jet for the treating of conduit surface. The treatment well improves cell affinity, blood compatibility and tissue compatibility of the conduit. It is also an environmental friendly technique that is ready to handle and easy to control. With all these advantages, the plasma treated nerve conduit has a high added value and a bright future.The auther generally discussed a series of ways for property evaluations of the nerve conduit. Based on a large number of experiments, a study was carried out on the effect of atmospheric pressure low temperature plasma jet treatment on nerve conduit surface property improvement. A carefully selected material and an optimized process were adopted to braid the conduit, coat with chitosan and to set the shape of the conduit. The atmospheric pressure plasma jet treatment on both nerve conduit and its material in this study is an innovative method for the surface modification. The results of facial morphology, mechanical property, hydrophilicity and cell affinity were obtained by the means of Scanning Electron Microscope(SEM) observation, mechanical strength testing, contact angle measuring, wicking property survey, X-ray Photoelectron Spectroscopic(XPS) analysis and in vitro cell culture experiment. The rules of different treating parameters and fabricating processes had on nerve regeneration were studied and an optimized treating parameter was obtained. Further more, an in vivo experiment is on the way.Based on all these in vitro evaluation results, several conclusions have been drawn. One of the most important ones is that a plasma treating parameter of 30W power and 5 treat times is comparatively better than others in modifying the surface properties of triaxial braided and chitosan coated PGLA nerve conduit.This study combines textile braiding and biomedicine with physical modification of plasma treatment to provide a better nerve conduit for tissue engineering. With reliable experimental results, this study greatly contributes to further researches on braided biodegradable peripheral nerve conduit and to the acceleration of clinical application of the conduit.