镧修饰羧基化氧石墨烯的抑菌性能

摘要

在氧化石墨烯(GO)的研究和应用中,为充分发挥其优良性质,必须对其进行功能化.笔者将稀土La3+离子接枝到羧基化的GO(GO-COOH)片层上,制备了一种功能化的镧修饰羧基化氧石墨烯(La/GO-COOH).利用红外光谱、热重分析和透射电镜等手段对合成的La/GO-COOH进行了表征,结果表明,La3+已通过化学和物理作用吸附在GO片层上.通过细菌生长动力学实验评价了La/GO-COOH的抑菌性能,结果表明,La/GO-COOH对大肠杆菌有很好的抑菌效果,当浓度为0.5 mg/mL,抑菌率达96.40％；对金黄色葡萄球菌和铜绿假单胞菌也均有抑菌效果,因此La/GO-COOH是具有抑菌性能的新型GO负载物；与未剥离的镧修饰氧化石墨(La/GTO)相比,由于剥离的GO片层的比表面积大,其吸附La3+离子的量高于氧化石墨(GTO),故La/GO-COOH复合物的抑菌性远优于La/GTO.%Graphene oxide ( GO) was functionalized by acetyl chloride to form carboxylated graphene oxide (GO-COOH). GO-COOH decorated with La particles with diameters between 0. 2 and 1 μm was prepared by the sonication of a LaCl3 aqueous solution with GO-COOH. The La-decorated GO-COOH was characterized by FT-IR, TGA and TEM, and its antibacterial properties were characterized by bacteria growth kinetics. Results showed that the La3+ ions were coordinated on edges and corrugated parts of the GO-COOH by physical and chemical bonding. The La-decorated GO-COOH had a good inhibitory efficiency of 96.4% on the E. coli when its concentration was 0. 5 mg/mL. It also had inhibitory effects on S. aureus and the P. Aeruginosa. The better antibacterial effect of the La-decorated GO-COOH than the corresponding La-decorated GTO was ascribed to the higher amount of La particles incorporated on the GO-COOH.