Preparation And Properties Of Bone Tissue Engineering Scaffolds Based On Bioactive Glass/Carbon Nanofibers

Bone tissue engineering scaffold material is a key issue in bone tissue engineering.Bioactive glass(BG)has good osseointegration ability,biocompatibility,and osteoconductivity,and has become a research focus of bone repair materials.Carbon nanofibers(Carbon nanofibers,CNFs)have excellent mechanical properties and good biocompatibility,and are often used as reinforcement materials in bone tissue repair.In this paper,a combination of sol-gel method and electrospinning technology were used to prepare BG/CNFs membranes.By adjusting the molar ratio of water to tetraethyl orthosilicate(TEOS),hydrolysis temperature and carbonization temperature of composite membranes,the effects of preparation process parameters on the morphology and structure of fibers and BG were investigated.The materials were characterized by SEM and TGA.The results showed that when the H2O/TEOS molar ratio was 8,the fiber had uniform thickness and less adhesion,and more BG particles on the fiber surface.When the hydrolysis temperature was 40?,spherical BG nanoparticles were evenly distributed on the fiber surface.As the carbonization temperature increases,the size of the nanoparticles on the fiber surface tends to increase,but as the carbonization temperature further increases,the nanoparticles on the fiber surface aggregate and fuse;when the carbonization temperature increases to 1200?,no obvious nanoparticles were observed on the fiber surface.The optimal process conditions for preparing the BG/CNFs membranes were determined as H2O/TEOS molar ratio of 8,a hydrolysis temperature of 40?,and a carbonization temperature of 1000?.Based on this,BG was modified by introducing Cu ions to prepare Cu-BG/CNFs membranes.The effect of Cu doping on the morphology of membranes and Cu-BG were investigated by adjusting the concentration of Cu ions.The morphology and structure of Cu-BG/CNFs membranes were analyzed by SEM,X-ray energy spectroscopy(EDS),high-resolution transmission electron microscope(HR-TEM),X-ray diffractometer(XRD),Fourier infrared test(FTIR),X-ray photoelectron spectroscopy(XPS).The results showed that with the increase of Cu ions content,the morphology of the fibers and BG nanoparticles didn't change significantly.After acidic hydrolysis,the low crystallinity of one-dimensional linear BG nanoparticles were mainly ?-CaSiO3.In vitro culture of mouse preosteoblast cells(MC3T3-E1)showed that the cells spread well on Cu-doped BG/CNFs membranes,and 5Cu-BG/CNFs membranes containing 5%Cu showed a certain inhibitory effect on cells.Finally,in order to improve the flexibility of the BG/CNFs membranes,we prepared ZrO2@BG/CNFs membranes doped with zirconium dioxide(ZrO2),and tested them by SEM,EDS,HR-TEM,XRD,FTIR,XPS and other test methods.The results showed that with the increase of the carbonization holding time,the BG particles on the surface of the ZrO2@BG/CNFs membranes first increase and then decrease.BG mainly exists in the form of?-CaSiO3 and Ca3(Si3O9),and the main phase of ZrO2 is tetragonal phase(T-ZrO2).By adding ZrO2 nanoparticles,ZrO2@BG/CNFs membranes exhibits flexible and bendable properties.In vitro culture of mouse preosteoblast cells(MC3T3-E1)showed that the cells grew and proliferated well on ZrO2@BG/CNFs membranes.ZrO2@BG/CNFs membranes with good flexibility,plasticity,and biological properties were successfully prepared,which solve the brittleness problem of CNFs and will further expand the application of BG/CNFs nanofiber composites in the field of bone tissue engineering.