Materials Engineering Center, UdR INSTM, University of Perugia , Str. Pentima 4, 05100 Terni, Italy.
Biomacromolecules. 2013 Mar 11;14(3):626-36. doi: 10.1021/bm301524e. Epub 2013 Feb 28.
The purpose of this study is to investigate the combined effects of oxygen plasma treatments and silver nanoparticles (Ag) on PLGA in order to modulate the surface antimicrobial properties through tunable bacteria adhesion mechanisms. PLGA nanocomposite films, produced by solvent casting with 1 wt % and 7 wt % of Ag nanoparticles were investigated. The PLGA and PLGA/Ag nanocomposite surfaces were treated with oxygen plasma. Surface properties of PLGA were investigated by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), static contact angle (CA), and high resolution X-ray photoelectron spectroscopy (XPS). Antibacterial tests were performed using an Escherichia coli RB (a Gram negative) and Staphylococcus aureus 8325-4 (a Gram positive). The PLGA surface becomes hydrophilic after the oxygen treatment and its roughness increases with the treatment time. The surface treatment and the Ag nanoparticle introduction have a dominant influence on the bacteria adhesion and growth. Oxygen-treated PLGA/Ag systems promote higher reduction of the bacteria viability in comparison to the untreated samples and neat PLGA. The combination of Ag nanoparticles with the oxygen plasma treatment opens new perspectives for the studied biodegradable systems in biomedical applications.
本研究旨在探讨氧等离子体处理和银纳米粒子（Ag）对聚乳酸-羟基乙酸共聚物（PLGA）的联合作用，通过可调的细菌黏附机制来调节表面抗菌性能。通过溶剂浇铸法制备了含有 1wt%和 7wt%Ag 纳米粒子的 PLGA 纳米复合材料薄膜。对 PLGA 和 PLGA/Ag 纳米复合材料表面进行了氧等离子体处理。采用场发射扫描电子显微镜（FESEM）、原子力显微镜（AFM）、静态接触角（CA）和高分辨率 X 射线光电子能谱（XPS）研究了 PLGA 的表面性质。采用大肠杆菌 RB（革兰氏阴性菌）和金黄色葡萄球菌 8325-4（革兰氏阳性菌）进行了抗菌试验。氧处理后，PLGA 表面变得亲水，其粗糙度随处理时间的增加而增加。表面处理和 Ag 纳米粒子的引入对细菌黏附和生长有主导影响。与未处理的样品和纯 PLGA 相比，经氧处理的 PLGA/Ag 体系能更有效地降低细菌的存活率。Ag 纳米粒子与氧等离子体处理的结合为研究的生物降解系统在生物医学应用中开辟了新的前景。
