Antibacterial effect of Ag-doped TiO2 nanoparticles incorporated natural rubber latex foam under visible light conditions

摘要

Ag-doped TiO2 nanoparticles (Ag-TiO2 NPs) incorporated into natural rubber latex foam (NRLF) showed enhanced antimicrobial activities under visible light. Synthesis of Ag-TiO2 NPs and their incorporation into NRLF are investigated in this paper. Synthesized Ag-TiO2 nano-powder was evaluated by powder X-ray diffraction (XRD) technique, surface electron microscopy (SEM), and high-resolution transmission electron micrograph (HRTEM) coupled with energy dispersive X-ray (EDX) technique. The modified NRLF materials were also evaluated by SEM-EDX analysis, XRD analysis, and antibacterial susceptibility tests. It was found that the XRD peaks obtained for the Ag-TiO2 NP perfectly matched with the reference code of 98-010-5393 which was the tetragonal type anatase phase of TiO2. Most of XRD peaks obtained for the modified NRLF matched with those of Ag-TiO2 NPs which confirmed the presence of nano Ag-TiO2 NPs in the modified NRLF. The particle size analysis carried out by HRTEM images and the EDX mapping results showed that the Ag nanoparticles with a diameter of 5 nm were simply attached to the surface of TiO2 nanoparticles. Modified NRLF showed antimicrobial activity against Gram positive Staphylococcus epidermidis, Gram-positive methicillin-resistant Staphylococcus aureus and Gram-negative Escherichia coli (strain numbers HB101, DH5d) bacteria species.