title: Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties.
abstract: A simple chemical method was developed for preparing high valence silver (Ag)-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA)-SBA-15), which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) analysis, and transmission electron microscopy (TEM). Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II) and Ag(III). However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15.
authors.affiliation: Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, 195 Chung Hsing Road, Chutung, Hsinchu County 31040, Taiwan. chunchi@itri.org.tw.
authors.forename: Chun-Chi
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, 195 Chung Hsing Road, Chutung, Hsinchu County 31040, Taiwan. cookwu@itri.org.tw.
authors.forename: Hsin-Hsien
authors.initials: HH
authors.lastname: Wu
authors.affiliation: Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, 195 Chung Hsing Road, Chutung, Hsinchu County 31040, Taiwan. cynthia.h@itri.org.tw.
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Huang
authors.affiliation: Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, 195 Chung Hsing Road, Chutung, Hsinchu County 31040, Taiwan. Chenwei@itri.org.tw.
authors.forename: Chen-Wei
authors.initials: CW
authors.lastname: Liu
authors.affiliation: Department of Bioscience Technology, Chung Yuan Christian University, 200 Chung Pei Road, Chung Li District, Taoyuan City 32023, Taiwan. yining@cycu.edu.tw.
authors.forename: Yi-Ning
authors.initials: YN
authors.lastname: Chen
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis*; D004492:Edetic Acid / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D012822:Silicon Dioxide / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D012834:Silver; D012822:Silicon Dioxide; D004492:Edetic Acid
keywords: SBA-15; antibacterial activity; high valence; silver