The Development Of A Tissue Engineering Biomaterial Used To Repair Injured Nerve And Research Of Its Biocompatibility And Biomechanics

It's very common of injury of spinal cord and peripheral nerve in our daily life, and how to repair the injured spinal cord and peripheral nerve is a tough problem in medical science. It's a focus that how to utilize different methods to repair the gap of injured spinal cord and peripheral nerve right along. It was proved that it is a good method that to utilize a tissue engineering biomaterial to repair the gap of injured spinal cord and peripheral nerve.Some of the questions are still not solved, though a lot of results based on kinds of experiments were reported: firstly, how to guide the reproductive neurofiber to grow directional; secondly, how to control absorbability of the biomaterial; thirdly, what about the biocompatibility of the biomaterial.Based on the above questions, we developed a tissue engineering biomaterial to repair the gap of injured spinal cord and peripheral nerve and its productive method. And we also detected the biocompatibility of the biomaterial. Production Of A Tissue Engineering Biomaterial[Materials] collagen-1 ,collagen-IV, aminoglycan, gelatine[method] To manufacturing a collagen-glycosaminoglycan matrix, we dip the silica gel-tubing filled with suspension of collagenand gelatin into the liquid nitrogen(-180C) with controllable dipping speed . The suspension is frozen into a kind of cylindral solid ,then we lyophilize it. Through the light microscope and scanning electron microscope we can observed that plenty of parallel microchannel into the biomaterial, and its size has relationship with dipping-speed . The size can be measured.[Result] The microchannel shows no regularity with a dipping-speed faster than 5 X 10-4m s-1. If the dipping-speed is slower than 2X10-5m s-1, the microchannel also shows no regularity, meantime ,the size of the microchannel is less than the others .When you dip the material into the liquid nitrogen with a speed of 2X 10-5m s-1 ,you can obtain the biomaterial with parallel microchannel which has the biggest diameters.Detection Of The Biocompatibility Of The Biomaterial[Materials] some of the 2 cm sterilized biomaterials[method] To detect the mechanical characteristic andbiocompatibility of the biomaterial ,we grafted the biomaterial into themuscles of the mice and detected the histopathological response andblood-biochemistry and immunology.[Result] Foreign body reaction could be observed at the earlyperiod of the implantation of the material in the muscle of the mice.Phlogistic cells disappeared after 4 weeks. The morphology and thefunction of the liver and the kidney are normal . The incision at theimplantation site heals well in seven days.Detection Of Biomechanics Characteristic Of The biomaterial [Materials] some of the 4 cm sterilized biomaterials [method] To detect biomechanics characteristic of thebiomaterials we draw the biomaterials which are separated for 5groups by different freezing velocity fore-and-aft.[Result] It has been proved that there is close relation betweenthe biomechanics characteristic of the biomaterials and its differentfreezing velocity.[Conclusion] Collagen-gelatin matrix with axial parallelmicrochannel of different diameters could be obtained through controlling the dipping speed of the silica gel-tubing filled with suspension of collagen and gelatin into the liquid nitrogen. This kind of biomaterial has well biocompatibility and can be used in the theatment of injury of the spinal cord and peripheral nerve both in experiment and clinic. We can also make the biomechanics characteristic of the biomaterials better through controlling the dipping speed of the silica gel-tubing filled with suspension of collagen and gelatin into the liquid nitrogen.It has been proved that the biomaterial has no cytotoxicity and has well tolerance. It is good for the growth and myelinization of the regeneration of the axon.