Department of Medical, Surgical and Health Sciences, University of Trieste, Piazza dell'Ospitale 1, 34129, Trieste, Italy.
J Mater Sci Mater Med. 2013 Jul;24(7):1799-807. doi: 10.1007/s10856-013-4923-4. Epub 2013 Apr 4.
In this study nano-composite scaffolds to be used as bone grafts have been endowed with antibacterial properties owing to the presence of silver nanoparticles. The alginate/hydroxyapatite composite scaffolds were prepared by internal gelation followed by a freeze-drying procedure to obtain a porous structure. The nanoparticles were prepared in presence of a lactose modified-chitosan and this colloidal solution was adsorbed on the scaffolds by exploiting electrostatic interactions. The adsorption and release of the silver from the composite scaffold was measured by ICP-AES and spectrofluorimetry measurements. Micro-computed tomography analysis of the scaffolds showed a homogeneous porous structure with average pore sizes of 341.5 μm and porosity of 80 %. In vitro biological tests (MTS and killing kinetics assays) demonstrated that silver does not affect the ability of the scaffolds to promote osteoblasts proliferation and that at the same time it exerts a strong bactericidal effect against both Gram+ and Gram- bacterial strains. Overall, the combined results indicate that these biocompatible antimicrobial scaffolds possess ideal characteristics for tissue engineering applications.
在这项研究中，由于纳米银粒子的存在，纳米复合材料支架被赋予了抗菌性能，可作为骨移植物。海藻酸/羟基磷灰石复合支架是通过内部凝胶化和冷冻干燥工艺制备的，以获得多孔结构。纳米粒子是在乳糖改性壳聚糖的存在下制备的，通过静电相互作用将该胶体溶液吸附在支架上。通过 ICP-AES 和荧光光谱法测量来测量复合材料支架中银的吸附和释放。支架的微计算机断层扫描分析显示出均匀的多孔结构，平均孔径为 341.5μm，孔隙率为 80%。体外生物学测试（MTS 和杀菌动力学测定）表明，银不会影响支架促进成骨细胞增殖的能力，同时对革兰氏阳性和革兰氏阴性细菌菌株均具有很强的杀菌作用。总的来说，综合结果表明，这些具有生物相容性的抗菌支架具有组织工程应用的理想特性。
