Niño-Martínez N, Martínez-Castañón G A, Aragón-Piña A, Martínez-Gutierrez F, Martínez-Mendoza J R, Ruiz Facundo
Facultad de Ciencias, UASLP, Álvaro Obregón 64, CP 78000, San Luis Potosí, SLP, Mexico. Instituto de Metalurgia, Facultad de Ingeniería, UASLP, Álvaro Obregón 64, CP 78000, San Luis Potosí, SLP, Mexico.
Nanotechnology. 2008 Feb 13;19(6):065711. doi: 10.1088/0957-4484/19/6/065711. Epub 2008 Jan 23.
Silver nanoparticles with a narrow size distribution were synthesized over the surface of two different commercial TiO(2) particles using a simple aqueous reduction method. The reducing agent used was NaBH(4); different molar ratios TiO(2):Ag were also used. The nanocomposites thus prepared were characterized using transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), dynamic light scattering (DLS) and UV-visible (UV-vis) absorption spectroscopy; the antibacterial activity was assessed using the standard microdilution method, determining the minimum inhibitory concentration (MIC) according to the National Committee for Clinical Laboratory Standards. From the microscopy studies (TEM and STEM) we observed that the silver nanoparticles are homogeneously distributed over the surface of TiO(2) particles and that the TiO(2):Ag molar ratio plays an important role. We used three different TiO(2)Ag molar ratios and the size of the silver nanoparticles is 10, 20 and 80 nm, respectively. It was found that the antibacterial activity of the nanocomposites increases considerably comparing with separated silver nanoparticles and TiO(2) particles.
采用简单的水相还原法，在两种不同的商用TiO₂颗粒表面合成了尺寸分布窄的银纳米颗粒。使用的还原剂是NaBH₄；还采用了不同的TiO₂:Ag摩尔比。对如此制备的纳米复合材料进行了透射电子显微镜（TEM）、扫描透射电子显微镜（STEM）、扫描电子显微镜（SEM）、能量色散光谱（EDS）、X射线光电子能谱（XPS）、X射线衍射（XRD）、动态光散射（DLS）和紫外可见（UV-vis）吸收光谱表征；采用标准微量稀释法评估抗菌活性，根据美国国家临床实验室标准委员会确定最低抑菌浓度（MIC）。通过显微镜研究（TEM和STEM）我们观察到银纳米颗粒均匀分布在TiO₂颗粒表面，且TiO₂:Ag摩尔比起着重要作用。我们使用了三种不同的TiO₂:Ag摩尔比，银纳米颗粒的尺寸分别为10、20和80纳米。结果发现，与分离的银纳米颗粒和TiO₂颗粒相比，纳米复合材料的抗菌活性显著提高。
