| 초록 |
Infectious diseases and their resulting deaths via contact with germ-contaminated surfaces are very serious problems globally. Zinc oxide (ZnO) and silver have been identified as attractive antibacterial agents, thanks to the great antibacterial activity and low toxicity to human. Firstly, to evaluate the funtional sustainment of ZnO antibacterial film in an ozone disinfection system, ZnO films synthesized via sol-gel/spin-coating were subjected to ultraviolet-ozone (UVO) treatment for different periods. Despite the surface changes (porosity increase and Zn(OH)2-to-ZnO chemical transformation), the satisfactory antibacterial activity of the synthesized ZnO film against Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli) was sustained even after 120 min UVO treatment. Secondary, to enhance the antibacterial activity, a AgNW film fabricated by spin-coating method were subjected to surface irradiation up to a dose of 1200 kGy by a low-energy electron beam (e-beam). Due to the generation of microscale and nanoscale silver oxide truncated spherical islands over AgNW fillm, the antibacterial activity of the e-beam irradiated AgNW film increase from 93.5 to 97.3 and 96.1 to 99.9 % for S. aureus and E. coli, respectively. Thirdly, the antibacterial activity of a AgNW film was improved via post-heat treatment. AgNW films were prepared by spin-coating, and then heated at different temperatures (230 and 280 oC) for 30 min. With increasing the heat-treatment temperature, the AgNWs broke into more discrete wires and droplets, and became more oxidized. These morphological and chemical changes enhanced the antibacterial activity; heat-treatment at 280 oC improved the antibacterial activity against from E. coli from 92.6 to 95.7 %. |
