Membrane Disruption Potential of Doped Cuprous Oxide Nanoparticles Against bla_NDM-1 and mcr-1 Positive Colistin Resistant E. coli

Bacterial resistance against the last-resort antibiotic “colistin” is a growing problem worldwide. Novel strategies in the field of nanotechnology for the development of suitable antibacterial drug with minimal toxicities are need of the time. Here we synthesized, Cu₂O nanoparticles (Cu₂O-NPs) doped with 5% Zn metal ions by adopting solution-phase method using hydrazine reduction in aqueous medium. Antibacterial assays showed a promising activity against colistin-resistant Escherichia coli isolates. Leakage assay, propidium iodide uptake assay, EtBr uptake assay, and LIVE/DEAD® BacLight™ assay showed membrane damaging activity of Cu₂O-NPs. Imaging by scanning electron microscopy of NP-treated bacterial cells confirmed membrane damaging potential of used Cu₂O-NPs. Toxicity assessment by cell viability assay showed no cytotoxic activity to the HEK cell line. In conclusion, our results suggest that Cu₂O-NPs doped with 5% Zn may exert their antimicrobial action by disruption of the bacterial cell membrane and probably generating reactive oxygen species (ROS). We suggest that Cu₂O-NPs doped with 5% Zn can be used as effective antibacterial agent. Graphical abstract: [Figure not available: see fulltext.].