无机纳米粒子掺杂生物活性碳纳米纤维的制备及性能评价

Inorganic nanoparticles-embedded bioactive carbon nanofibers: Preparation and performance evaluation

背景:已有研究表明向生物惰性碳纳米纤维中引入具有成骨活性的β-磷酸三钙纳米粒子,可显著提高碳纳米纤维的生物活性,而某些二价离子掺杂的β-磷酸三钙也被报道能够促进新骨的生成。目的:考察适量锌离子、镁离子的引入对β-磷酸三钙@碳纳米纤维材料形貌及成骨活性的影响。方法:以聚丙烯腈、磷酸三乙酯、硝酸钙、硝酸锌、硝酸镁等为原料,采用溶胶-凝胶、静电纺丝与原位烧结碳化相结合的方法制备锌或镁离子掺杂的β-磷酸三钙@碳纳米纤维材料。将所得复合纳米纤维材料及未掺杂锌或镁离子掺杂的β-磷酸三钙@碳纳米纤维与成骨细胞MC3T3-E1体外共培养,观察细胞的黏附、增殖和形态变化。结果与结论:β-磷酸三钙@碳纳米纤维形貌均匀,表面可见直径为数十纳米的无机粒子均匀分布,锌或镁离子的引入对纤维形貌无明显影响;复合纤维主要由碳元素组成,钙、锌、镁元素等均匀分布于纤维中,且各元素相对含量与投料比相符。与未掺杂锌或镁离子的β-磷酸三钙@碳纳米纤维相比,MC3T3-E1成骨细胞更易在锌或镁离子掺杂的β-磷酸三钙@碳纳米纤维材料表面黏附,细胞增殖和铺展状态也更好。表明在β-磷酸三钙@碳纳米纤维的基础上,引入锌或镁离子掺杂,能进一步提高材料的细胞相容性及生物活性。

BACKGROUND：It has been identified that the introduction ofβ-tricalcium phosphate nanoparticles, which have good osteogenetic activity, into bio-inert carbon nanofibers can significantly improve the biological activity of carbon nanofibers. Furthermore, it has also been reported that bivalent ions dopedβ-tricalcium phosphate compounds can promote the new bone formation. OBJECTIVE：To investigate the effect of incorporation of Zn2＋, Mg2＋on the fiber morphology and the osteogenetic activity ofβ-tricalcium phosphate@carbon nanofibers. METHODS：To prepare Zn2＋/Mg2＋dopedβ-tricalcium phosphate@carbon nanofibers composite nanofibers, electospinning of polyacrylonitrile solution was combined with CaP sol-gel solution by using triethyl phosphate, calcium nitrate, zinc nitrate and/or magnesium nitrate as precursors. The carbon nanofiber composite was obtained by pre-oxidizing and carbonizing the as-electrospun nanofibers. By in vitro co-culture with mouse osteoblast-like cel s （MC3T3-E1）, the effect of Zn2＋/Mg2＋doping intoβ-tricalcium phosphate@carbon nanofibers on cel behaviors were evaluated via comparison of cel adhesion efficiency, proliferation and morphology. RESULTS AND CONCLUSION：The obtained Zn2＋/Mg2＋dopedβ-tricalcium phosphate@carbon nanofibers demonstrated uniform and smooth fiber surface with no bead-in-string structure. Inorganic particles in nanoscale could be seen clearly on the fiber surface and throughout the fiber. Determined by element analysis, it was revealed that the composite fibers were mainly composed of carbon, and the calcium element. The mapping of Mg and Zn showed their distribution was even and their amounts were coincident to feed ratios. Compared to non-dopingβ-tricalcium phosphate@carbon nanofibers, MC3T3-E1 showed enhanced biological behaviors on Zn2＋or Mg2＋dopedβ-tricalcium phosphate@carbon nanofibers matrixes, like cel adhesion, spreading, and proliferation being promoted. The results suggested that ions dopedβ-tricalcium phosphate@carbon nanofibers with higher cytocompatibility and bioactivity might be a kind of attractive substrate for bone regeneration.