Drug-resistant bacteria and bacteria that form resilient biofilms are important problems in healthcare. Catalysts that promote the production of reactive oxygen species (ROS), which can kill bacteria, could help to tackle these issues. Metal- or metal-oxide-based nanomaterials can be useful for this type of application.
Amit Kumar, In Su Lee, Pohang University of Science and Technology, Republic of Korea, Yoon-Kyoung Cho, Ulsan National Institute of Science and Technology (UNIST), Republic of Korea, and colleagues have developed an approach to eradicating antibiotic-resistant bacteria in biofilms using mixed-FeCo-oxide-based surface-textured nanostructures. First, the researchers synthesized a composite consisting of β-FeOOH spheroidal nanorods coated with graphene oxide and poly(tannic acid). The composite was treated with Co(NO3)2, which caused the deposition of Co(OH)2 granules on the surface. Then, the material was annealed in air at temperatures of 500–700 °C.
During the annealing process, the metal ions are mixed by a solid-state chemical reaction on the nanocrystal surface and nanosized branches and holes are created. The team found that this surface texture increases the mobility of nanoparticles and allows efficient diffusion into a biofilm matrix. The nanocrystals showed a high catalytic activity in ROS generation over a broad pH range, and thus, can kill drug-resistant bacteria. The nanoparticles are magnetic, which allows their easy manipulation, e.g., to remove biofilms from microfluidic channels.
- Surface-Textured Mixed-Metal-Oxide Nanocrystals as Efficient Catalysts for ROS Production and Biofilm Eradication,
Nitee Kumari, Sumit Kumar, Mamata Karmacharya, Sateesh Dubbu, Taewan Kwon, Varsha Singh, Keun Hwa Chae, Amit Kumar, Yoon-Kyoung Cho, In Su Lee,
Nano Lett. 2020.