id9b00279_si_001.pdf (1.39 MB)
Antibacterial Surfaces with Activity against Antimicrobial Resistant Bacterial Pathogens and Endospores
journal contribution
posted on 2020-03-11, 19:14 authored by Sandeep K. Sehmi, Claudio Lourenco, Khaled Alkhuder, Sebastian D. Pike, Sacha Noimark, Charlotte K. Williams, Milo S. P. Shaffer, Ivan P. Parkin, Alexander J. MacRobert, Elaine AllanHospital-acquired
bacterial infections are a significant burden on healthcare systems
worldwide causing an increased duration of hospital stays and prolonged
patient suffering. We show that polyurethane containing crystal violet
(CV) and 3–4 nm zinc oxide nanoparticles (ZnO NPs) possesses
excellent bactericidal activity against hospital-acquired pathogens
including multidrug resistant Escherichia coli (E. coli), Pseudomonas aeruginosa,
methicillin-resistant Staphylococcus aureus (MRSA),
and even highly resistant endospores of Clostridioides (Clostridium)
difficile. Importantly, we used clinical isolates of bacterial
strains, a protocol to mimic the environmental conditions of a real
exposure in the healthcare setting, and low light intensity equivalent
to that encountered in UK hospitals (∼500 lux). Our data shows
that ZnO NPs enhance the photobactericidal activity of CV under low
intensity light even with short exposure times, and we show that this
involves both Type I and Type II photochemical pathways. Interestingly,
polyurethane containing ZnO NPs alone showed significant bactericidal
activity in the dark against one strain of E. coli, indicating that the NPs possess both light-activated synergistic
activity with CV and inherent bactericidal activity that is independent
of light. These new antibacterial polymers are potentially useful
in healthcare facilties to reduce the transmission of pathogens between
people and the environment.