Fu Guifen, Vary Patricia S, Lin Chhiu-Tsu
Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115-2862, USA.
J Phys Chem B. 2005 May 12;109(18):8889-98. doi: 10.1021/jp0502196.
A sol-gel chemistry approach was used to fabricate nanoparticles of TiO(2) in its anatase form. The particle size is shown to be sensitive to the use of HClO(4) or HNO(3) as acid catalyst. The gold-capped TiO(2) nanocomposites were processed by the reduction of gold on the surface of the TiO(2) nanoparticles via a chemical reduction or a photoreduction method. Different percentages of vanadium-doped TiO(2) nanoparticles, which extended the TiO(2) absorption wavelength from the ultraviolet to the visible region, were successfully prepared. The synthesized nanocomposites have a size of about 12-18 nm and an anatase phase as characterized by XRD, TEM, AFM, and UV-vis spectroscopy. The TiO(2) nanocomposite coatings have been applied on glass slide substrates. The antibacterial activity of TiO(2) nanocomposites was investigated qualitatively and quantitatively. Two types of bacteria, Escherichia coli (DH 5alpha) and Bacillus megaterium (QM B1551), were used during the experiments. Good inhibition results were observed and demonstrated visually. The quantitative examination of bacterial activity for E. coli was estimated by the survival ratio as calculated from the number of viable cells, which form colonies on the nutrient agar plates. The antimicrobial efficiency and inhibition mechanisms are illustrated and discussed.
采用溶胶-凝胶化学方法制备锐钛矿型TiO₂纳米颗粒。结果表明，颗粒尺寸对使用HClO₄或HNO₃作为酸催化剂较为敏感。通过化学还原或光还原方法在TiO₂纳米颗粒表面还原金，制备了金包覆的TiO₂纳米复合材料。成功制备了不同百分比的钒掺杂TiO₂纳米颗粒，其将TiO₂的吸收波长从紫外区域扩展到了可见区域。通过XRD、TEM、AFM和紫外-可见光谱表征，合成的纳米复合材料尺寸约为12-18 nm，且为锐钛矿相。TiO₂纳米复合涂层已应用于载玻片基底上。对TiO₂纳米复合材料的抗菌活性进行了定性和定量研究。实验中使用了两种细菌，即大肠杆菌（DH 5α）和巨大芽孢杆菌（QM B1551）。观察到了良好的抑制效果，并通过视觉进行了展示。通过计算在营养琼脂平板上形成菌落的活细胞数量得出的存活率，对大肠杆菌的细菌活性进行了定量检测。阐述并讨论了抗菌效率和抑制机制。
