title: Micro-structural evolution and biomineralization behavior of carbon nanofiber/bioactive glass composites induced by precursor aging time.
abstract: Bioactive glass (BG)-containing carbon nanofibers (CNFs) are promising orthopaedic biomaterials. Herein, CNF composites were produced from electrospinning of polyacrylonitrile (PAN)/BG sol-gel precursor solution, followed by carbonization. Choosing 58S-type BG (mol%: 58.0% SiO2-26.3% CaO-15.7% P2O5) as the model, micro-structural evolution of CNF/BG composites was systematically evaluated in relating to aging times of BG precursor solution. With aging time prolonging, BG precursors underwent morphological changes from small sol clusters with loosely and randomly branched structure to highly crosslinked Si-network structure, showing continuous increase in solution viscosity. BG precursor solution with low viscosity could mix well with PAN solution, resulting in CNF composite with homogeneously distributed BG component. Whereas, BG precursor gel with densely crosslinked Si-network structure led to uneven distribution of BG component along final CNFs due to its significant phase separation from PAN component. Meanwhile, BG nanoparticles in CNFs demonstrated micro-structural evolution that they transited from weak to strong crystal state along with longer aging time. Biomineralization in simulated body fluid and in vitro osteoblasts proliferation were then applied to determine the bioactivity of CNF/BG composites. CNF/BG composites prepared from shorter aging time could induce both faster apatite deposition and cell proliferation rate. It was suggested weakly crystallized BG nanoparticles along CNFs dissolved fast and was able to provide numerous nucleation sites for apatite deposition, which also favored the proliferation of osteoblasts cells. Aging time could thus be a useful tool to regulate the biological features of CNF/BG composites.
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China; Changzhou Institute of Advanced Materials, Beijing University of Chemical Technology, Jiangsu 213164, PR China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Jia
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Tianhong
authors.initials: T
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Dan
authors.initials: D
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Cuihua
authors.initials: C
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Ran
authors.initials: R
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China; Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, PR China. Electronic address: caiqing@mail.buct.edu.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Cai
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China; Changzhou Institute of Advanced Materials, Beijing University of Chemical Technology, Jiangsu 213164, PR China; Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Yang
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001031:Apatites / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D049109:Cell Proliferation; D005898:Glass / Q000737:chemistry*; D008422:Materials Testing; D051379:Mice; D057139:Nanofibers / Q000737:chemistry*
chemical_list: D001031:Apatites; D002244:Carbon
keywords: Aging time; Bioactive glass; Carbon nanofibers; Micro-structure; Sol–gel