Study On Preparation Of Patterned Silk Fibroin Fibrous Mat By Electrospinning And Its Biological Performance

t is a core research topic and direction in the field of biomaterials and tissue engineering to regulate cell behavior and provide growth support for newborn tissues through the micro/nano structure of biomaterials.Micro-nanofiber materials prepared by electrostatic spinning technology can mimic the natural extracellular matrix(ECM)on the micro scale.At this stage,it has become a cross-research hotspot and attracted extensive attention from scholars.Silk fibroin has good biocompatibility,so the construction of silk fibroin scaffold material using electrospinning technology can bring new opportunities and solutions for tissue repair and regeneration.In this dissertation,based on the electrospinning technology,we focused on the design and construction of a new type of array electrospinning receiving device,and successfully prapared a patterned silk fibroin fibrous mat with an ordered/disordered array arrangement through this new receiving device.The effects of different solvent systems on the spinnability of the spinning solution were systematically investigated,and the effects of post-treatment methods on the physicochemical properties of the electrospun silk fibroin fibrous mat were also discussed.At the same time,the effects of the size and the spatial arrangement ratio of the ordered/disordered pattern area of electrospinning mat on the mechanical properties of the silk fibroin fibrous mat were also studied.In addition,in vitro cell culture experiments were conducted to study the microstructure of the patterned silk fibroin fibrous mat,especially the orientation of silk fibroin microfibers to control the cell growth behavior and its in vitro degradation performance.The main research conclusions are outlined as follows:(1)The effects of different solvent systems on the spinnability of the spinning solution and the effects of post-treatment methods on the physicochemical properties of silk fibroin fibrous membranes were systematically investigated.The results show that the spinning solution of the methanol solution system with a silk fibroin concentration of 12 wt%has the best spinnability.By adjusting the appropriate electrospinning experiment parameters and receiving device,disordered and ordered electrospinning silk fibroin film can be successfully obtained,and the obtained silk fibroin microfibers have uniform size and smooth surface.Compared with the water vapor vacuuum post-treatment method,the alcohol post-treatment method can not only effectively promote the conversion of the silk fibrin membrane material to a more stable ?-sheet structure,but also maintain a good microfiber morphology,with the best insoluble treatment effect.(2)Designed a new type of array electrospinning receiving device with a special structure was designed.The larger-sized patterned silk fibroin fiber membrane materials with ordered/disordered array arrangement were successfully prepared by such new receiving device.The prepared patterned silk fibroin fiber membrane has high yield and good orientation microfiber orientation.By setting the size of the ordered and disordered collection areas of the array-type receiving device,the size of the ordered and disordered areas in the patterned silk fibroin fibrous mat can be effectively controlled.And the ordered fibrous in the obtained patterned silk fibroin fibrous mat had the highest degree of order when the ordered collection area is 10 mm.(3)The results of mechanical property test indicate that the electrospun silk fiber membrane exhibits different mechanical properties in dry state and wet state.The breaking strength of the test sample in the dry state is higher than that in the wet state.And the appropriate proportion of the patterned silk fibroin fiber membrane material(O2R1)has good mechanical properties in both the dry state and the wet state.(4)The results of in vitro cell culture experiments indicate that compared with flat silk fibroin membranes,the electrospun silk fibroin fibrous mat can provide a micro-environment which is more conducive to cell life activities and significantly enhance cell adhesion and growth.In addition,the orientation of the microfiber structure in the electrospun fibroin fiber membrane can affect the adherence morphology of the cells,and the surface of the ordered fibers area can effectively guide the cells to grow in the direction of the fibers.(5)The results of in vitro degradation experiments show that compared with the flat silk fibroin mat,the microfibre structure on the surface of the electrospun silk fibroin fiber membrane has a large specific surface area,and the existing microporous structure utilizes the infiltration of the degradation solution,so electrospinning silk fibroin fiber membrane has a faster degradation rate.At the same time,the spatial arrangement of the microfibr structure in the electrospun silk fibroin fibrous mat will have a certain degree of influence on its degradation process.In the presence of protease,the degradation rate of the patterned silk fibroin fibrous mat is lower than that of single-structure ordered and single-structure disordered electrospun silk fibroin fibrous mat.