In this study, we carried out a simple surface modification of zinc oxide nanoparticles (ZnO NPs) using didodecyldimethylammonium bromide (DDAB) as a cationic surfactant. The crystallographic properties, optical absorption, and morphology of the ZnO NPs did not change after the surface modification. The FT-IR spectra of the surface-modified ZnO NPs (SM-ZnO) showed the characteristic peaks of DDAB, which shifted to higher frequencies with an increase in the DDAB content. The zeta potential of the SM-ZnO NPs increased with an increase in the DDAB content and reaction time. The sedimentation test results revealed that the SM-ZnO NPs exhibited better dispersion and lower aggregation than pure ZnO NPs. The SM-ZnO NPs showed high surface positive charge, thereby generating additional Zn2+ with higher surface tendency to the bacteria. The SM-ZnO NPs showed improved antibacterial activity against both Staphylococcus aureus and Escherichia coli strains as compared to the pure ZnO NPs.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) and the Korean government (MSIP) [grant number 2020R1A2B5B01001797].
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Industrial and Manufacturing Engineering