Considering the global spread of bacterial infections,
the development
of anti-biofilm surfaces with high antimicrobial activities is highly
desired. This work unraveled a simple, sonochemical method for coating
Cu2O nanoparticles (NPs) on three different flexible substrates:
polyester (PE), nylon 2 (N2), and polyethylene (PEL). The introduction
of Cu2O NPs on these substrates enhanced their surface
hydrophobicity, induced ROS generation, and completely inhibited the
growth of sensitive (Escherichia coli and Staphyloccocus aureus) and drug-resistant
(MDR E. coli and MRSA) planktonic and
biofilm. The experimental results confirmed that Cu2O-PE
exhibited complete biofilm mass reduction ability for all four strains,
whereas Cu2O-N2 showed more than 99% biomass inhibition
against both drug-resistant and sensitive pathogens in 6 h. Moreover,
Cu2O-PEL also indicated a 99.95, 97.73, 98.00, and 99.20%
biomass reduction of MRSA, MDR E. coli, E. coli, and S. aureus, respectively. All substrates were investigated for time-dependent
inhibitions, and the associated biofilm mass and log reduction were
evaluated. The mechanisms of Cu2O NP action against the
mature biofilms include the generation of reactive oxygen species
(ROS) as well as electrostatic interaction between Cu2O
NPs and bacterial membranes. The current study could pave the way
for the commercialization of sonochemically coated Cu2O
NP flexible substrates for the prevention of microbial contamination
in hospitals and industrial environments.