| Bioglass is bone repair material which can only combined with bone and soft tissue, and it is highly bioactive. Carbon nano-fiber has received hot attention in many fields due to its excellent mechanical strength, big specific area, stable chemical property and can be easily surface functionalized properties. Considering the advantages of both materials, Bioglass@CNF composites with both highly bioactive and excellent mechanical property were prepared though sol-gel and electrospining method, and followed by hydrolization, pre-oxidation and carbonization. The aging time and Ca/P ratio of precursor solution were changed respectively to analyze the influence on structure evolution and biological properies of Bioglass@CNF.The relevance between aging time of precursor solution and structure evolution and biological properties of Bioglass@CNF has been studied in this paper. Viscosity analyzer, laser particle size analyzer and nuclear magnetic resonance analyzer were used to analyze the viscosity and elements’combination of Bioglass, and the optical microscope was also used to observe its formation process directly. These results show that the Si-O net being formed with time going by, and the longer the Si-O net can be formed better, with the viscosity increasing and particle size increasing before aging for 4 days and decreasing after 4 days. The NMR results also showed the increasing Si-O-Si structure which proved the Si-O net’s getting better with time going by. So the precursors were representatively aged for 1, 4 and 7 days respectively, and Bioglass@CNF-1d, Bioglass@CNF-4d and Bioglass@CNF-7d were prepared after the following steps of electrospining and carbonization. Bioglass@CNF with different aging time was characterized by scanning electron microscope(SEM), transmission electron microscope(TEM), high-resolution electron microscope(HR-TEM), infrared spectroscopy(FTIR) and X-ray diffraction(XRD), and results state that the aging of precursor affects ceramics’type and structure in Bioglass@CNF, which means amorphous calcium silicate was form in Bioglass@CNF-ld, crystalline wollastonite was formed gradually in Bioglass@CNF-4d and wollastonite’s crystallization turned to perfect and with some crystalline silicon was formed in Bioglass@CNF-7d. The results of mineralization showed that:Bioglass@CNF-1d revealed the fastest growth rate due to its amorphous calcium silicate, and when the calcium silicate is more crystalline the growth rate is more slowly. Meanwhile, the HCA grew on Bioglass@CNF-7d is inhomogeneous because of its heterogeneity of ceramic paticles.Meanwhile, the relevance between Ca/P ratio of precursor solution and structure evolution and biological properties of Bioglass@CNF has also been discussed in this paper. SEM, TEM, XRD and FTIR were used to analyze Bioglass@CNF’s structure, and results reveal that amorphous calcium phosphate and small crystalline calcium phosphate were formed when Ca/P is 1.0, the wollastonite was the major component when Ca/P is 1.67 and more wollastonite and some silicon were formed when Ca/P is 2.5. Then, biomineralization and cell culture of Bioglass@CNF with different Ca/P ratio were carried out, and the results of SEM, XRD and FTIR show that the small Ca/P ratio is the better biomineralization and cytocompatibility, and some calcium oxide harmful to cell was found when Ca/P is 2.5 which is bad for biomineralization and cell culture. |
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