Design And Vitro Activity Of Dissolved Controllable PEO/SA/BG Biomimetic Fibrous Scaffolds

With the acceleration of population aging,many elderly people's own metabolic rate has not kept pace with the aging of tissues and organs.When a certain part of the body is injured,it is hard to recover by its own function,and only by transplantation of the tissues and organs to be repaired.However,the transplanted tissue and organs have limited sources and is excluded by body.Therefore,extrinsic bioremediation materials must be considered for replacement.Bioactive glass(BG)is an inorganic biomaterial which can effectively promote the formation of hydroxyapatite,it has a high specific surface area,which is good for promoting the repair of human bone.However,the bioactive glass is powdery and unfavorable for direct application in clinic,therefore,it is necessary to prepare a reliable biological scaffold,while the electrospinning technique is a good method,the prepared nanofiber membrane has a property of high porosity,which is conducive to cell adhesion.Sodium alginate(SA)is a non-toxic,highly biocompatible natural polymer material,which has attracted much attention and extensive research in the field of biomaterials.For its structural characteristics,sodium alginate can not be electrospun separately.PEO is also a non-toxic polymer commonly used in electrospinning to improve the spinnability of spinning solution,thus,it was mixed with SA.Therefore,in this paper,PEO/SA/BG composite fiber scaffolds were prepared with PEO,SA and a certain amount of bioactive glass.The specific research are as follows:(1)Preparation and process parameters analysis of PEO/SA Fiber.The PEO and SA were added to deionized water according to different ratio,the rheological properties of spinning solution were measured by rheometer,the spinning solution was selected for electrospinning,the surface morphology of fiber was observed by scanning electron microscope,the best spinning concentration is 3% PEO/1% SA solution,which had prepared uniform and smooth fibers,and the average diameter of fibers is 105 ± 15 nm.Compared with the fibers before and after the addition of SA,it was found that composite fiber's diameter decreased with the addition of SA,it can be seen the addition of SA reduced the average fiber diameter.(2)Study on water solubility of PEO/SA fiber scaffolds.The PEO/SA fiber scaffolds were treated with aqueous calcium chloride and glutaraldehyde solution as a cross-linking agent to keep the structure of fiber in water for a certain time.The result of cross-linked fiber scaffold was evaluated by immersing it in deionized water for 3 days.In order to further confirm the microscopic structure of the fiber,the fiber scaffold was observed with a scanning electron microscope.It was found that the fiber structure was damaged,but still retained property of high porosity.And by measuring the surface contact angle of the fiber scaffold to measure its hydrophilic properties,concluded that the addition of SA is conducive to improving the hydrophilic properties of the fiber scaffold.(3)Preparation and study in vitro biological activity of PEO/SA/BG composite fiber scaffolds.Bioactive glass(BG)was prepared and added to the PEO/SA solution,PEO/SA/BG composite fiber scaffold was prepared by electrospinning with previous solution,which has the average fiber diameter of 108 ± 16 nm,the fiber surface is smooth and uniform.The vitro biological activity of the crosslinked scaffold was measured by soaking in SBF,the results showed that the surface structure of fiber membrane immersed in SBF was damaged,but the presence of hydroxyapatite was found on the surface of fiber,and further confirmed by EDS.In order to maintain its fiber structure,HMDI as a crosslinking agent with the addition of 2% DBTDL as a catalyst was applied,the crosslinked fiber membrane soaked in SBF still maintained a porous fiber network structure and production of hydroxyapatite were further confirmed by FTIR,XRD.In summary,PEO/SA/BG composite fiber membrane showed good biological activity in vitro,there is potential to be an alternative tissue and organ biodegradable materials.