Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
Int J Biol Macromol. 2018 May;111:923-934. doi: 10.1016/j.ijbiomac.2018.01.089. Epub 2018 Feb 19.
In the present work, we aimed to synthesize highly efficient nano-composite polymeric scaffolds with controllable pore size and mechanical strength. We prepared nanocomposite (CCNWs-AgNPs) of silver nanoparticles (AgNPs) decorated on carboxylated CNWs (CCNWs) which serves dual functions of providing mechanical strength and antimicrobial activity. Scaffolds containing chitosan (CS) and carboxymethyl cellulose (CMC) with varying percent of nanocomposite were fabricated using freeze drying method. XRD and FESEM analysis of nanocomposite revealed highly crystalline structure with AgNPs (5.2 nm dia) decorated on ~200 nm long CCNWs surface. FTIR analysis confirmed the interaction between CCNWs and AgNPs. Incorporation of nanocomposite during scaffolds preparation helped in achieving the desirable 80-90% porosity with pore diameter ranging between 150 and 500 μm and mechanical strength was also significantly improved matching with the mechanical strength of cancellous bone. The swelling capacity of scaffolds decreased after the incorporation of nanocomposite. In turn, scaffold degradation rate was tuned to support angiogenesis and vascularization. Scaffolds apart from exhibiting excellent antimicrobial activity, also supported MG63 cells adhesion and proliferation. Incorporation of CCNWs also resulted in improved biomineralization for bone growth. Overall, these studies confirmed excellent properties of fabricated scaffolds, making them self-sustained and potential antimicrobial scaffolds (without any loaded drug) to overcome bone related infections like osteomyelitis.
在本工作中，我们旨在合成具有可控孔径和机械强度的高效纳米复合聚合物支架。我们制备了纳米复合材料（CCNWs-AgNPs），其中银纳米颗粒（AgNPs）修饰在羧化的碳纳米管（CCNWs）上，具有提供机械强度和抗菌活性的双重功能。含有壳聚糖（CS）和羧甲基纤维素（CMC）的支架，其纳米复合材料的含量不同，是通过冷冻干燥法制备的。纳米复合材料的 XRD 和 FESEM 分析表明，AgNPs（5.2nm 直径）高度结晶的结构修饰在~200nm 长的 CCNWs 表面上。FTIR 分析证实了 CCNWs 和 AgNPs 之间的相互作用。在支架制备过程中加入纳米复合材料有助于获得理想的 80-90%的孔隙率，孔径范围在 150-500μm 之间，机械强度也显著提高，与松质骨的机械强度相匹配。加入纳米复合材料后，支架的溶胀能力下降。反过来，支架的降解速率被调整以支持血管生成和血管化。支架除了表现出优异的抗菌活性外，还支持 MG63 细胞的黏附和增殖。CCNWs 的加入也导致了更好的骨生长的生物矿化。总的来说，这些研究证实了所制备支架的优异性能，使其具有自支撑性和潜在的抗菌支架（无需任何负载药物），以克服与骨相关的感染，如骨髓炎。
