The Regulation Of Biomimetic Mineralization Of Hydroxyapatite In TSF Nanofiber Arrays And The Construction Of Bone Biomimetic Composite Materials

Regenerated pure tussah silk fibroin (TSF) and TSF/CS (Chitosan) blend nanofibers were prepared by electrospinning, and nanofiber arrays were obtained by using special collectors, then the morphology characteristics as well as the influence factors were analyzed theoretically. On the basis of this analysis, bone biomimetic composite materials were constructed by using biomimetic mineralization, subsequently the structure and properties were tested and analyzed, which provides theoretical basis for TSF/CS nanofiber arrays to use as materials in biomedical fields and bone tissue engineering.Electrospun pure tussah silk fibroin (TSF) nanofibers and TSF/CS (Chitosan) blend nanofibers were prepared by using HFIP as the solvent. The morphology was controlled by changing concentration of solution and using different collectors. The nanofiber is thin with beads when the concentration of TSF solution is 4%, but they will disappear when the concentration is 6% or above with the increasement of viscosity and diameter. At the same time, the nanofibers will become band-like morphology. The TSF/CS blend nanofibers at the ratio of 90/10 show a smaller and centralized diameter distribution. The conformation of TSF macromolecules will change fromα-helix toβ-sheet after steam treatment.The biomimetic mineralization on TSF nanofiber arrays was carried on by using biomimetic mineralization principle. The crystal deposition of HAP was verified by using polarizing microscope, FESEM, FTIR and XRD, whose growth was aligned along the fiber axial direction. This paper shows that the active groups of TSF macromolecules can provide active site for the growth of HAP. The rate of mineralization was regulated and analyzed by using a self-made mineralization device and changing the experimental conditions.Finally, the compressive mechanical properties of composite materials were studied. The research shows that the compressive properties of materials without biomimetic mineralization are poor. The compressive modulus, compressive strength and maximum load will be improved after biomimetic mineralization. The rate of mineralization and the diameter of nanofibers have impact on compressive capacity. The more the rate of mineralization, the better the compressive capacity. The larger the diameter of nanofibers, the worse the compressive capacity.