多巴胺包覆碳纳米管载银复合材料的制备及抑菌性能

Preparation and Antibacterial Properties of Nanosilver-Loaded Polydopamine Coated Multi-Wall Carbon Nanotubes

以多巴胺在弱碱性条件下自聚合的特点为基础,制备得到聚多巴胺包覆的多壁碳纳米管(PDA-MWCNTs)。然后,利用预合成的聚多巴胺膜层作为纳米导向使得均匀的纳米银粒子沉积在PDA-MWCNTs表面。在该体系中,壳聚糖作为保护剂和稳定剂,利用聚多巴胺的还原及吸附作用,通过原位化学还原法制备得到聚多巴胺包覆碳纳米管/纳米银/壳聚糖复合材料(CS/PDA-MWCNTs/Ag)。通过透射电子显微镜和X射线衍射对复合材料的结构和性能进行表征,分析表明:原位化学还原法比液相还原法更有效的增加了纳米银的附着率。所制得的复合材料具有广谱抑菌性对革兰氏阴性菌和革兰氏阳性菌均有很好的抑菌性能,进一步证实了壳聚糖与纳米银的协同效应可增强复合材料的抑菌性能。

On the basis of characteristic of dopamine self-polymerization under slightly alkaline solution, polydopamine (PDA) coated multi-wall carbon nanotubes (MWCNTs) was prepared. Then, the pre-synthesis polydopamine (PDA) layer was utilized as a nanoscale guide to form uniform Ag nanoparticles (Ag NPs) on the surface of PDA-MWCNTs. In this system, chitosan (CS) played a role of protective agent and stabilizer and through the reduction and adsorption action of the PDA layer, PDA coated MWCNTs/Ag NPs/CS composites (CS/PDA-MWCNTs/Ag) were prepared by in-situ chemical reduction. The structure and nature of CS/PDA-MWCNTs/Ag composites were investigated with TEM and XRD. Analysis indicated that the adhesive rate of Ag NPs by in-situ chemical reduction method was superior to liquid phase reducing method. The resulting composites had an efficient broad-spectrum of antibacterial activity against both Gram-negative and Gram- positive bacteria, which further confirmed the synergistic effect of CS and Ag NPs can enhance the antimicrobial properties of hybrid materials.