Enhancing the Antibacterial Activity of Light-Activated Surfaces Containing Crystal Violet and ZnO Nanoparticles: Investigation of Nanoparticle Size, Capping Ligand, and Dopants

Sandeep K Sehmi; Sacha Noimark; Sebastian D Pike; Joseph C Bear; William J Peveler; Charlotte K Williams; Milo S P Shaffer; Elaine Allan; Ivan P Parkin; Alexander J MacRobert

doi:10.1021/acsomega.6b00017

Enhancing the Antibacterial Activity of Light-Activated Surfaces Containing Crystal Violet and ZnO Nanoparticles: Investigation of Nanoparticle Size, Capping Ligand, and Dopants

ACS Omega. 2016 Sep 30;1(3):334-343. doi: 10.1021/acsomega.6b00017. Epub 2016 Sep 6.

Authors

Affiliations

¹ UCL Division of Surgery and Interventional Science, University College London, Royal Free Campus, Rowland Hill Street, London NW3 2PF, U.K.; Materials Chemistry Research Centre, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.; Division of Microbial Disease, UCL Eastman Dental Institute, University College London, 256 Gray's Inn Road, London WC1X 8LD, U.K.
² Department of Medical Physics and Biomedical Engineering, University College London , Gower Street, London WC1E 6BT, U.K.
³ Department of Chemistry, Imperial College London , Imperial College Road, London SW7 2AZ, U.K.
⁴ Materials Chemistry Research Centre, Department of Chemistry, University College London , 20 Gordon Street, London WC1H 0AJ, U.K.
⁵ Division of Microbial Disease, UCL Eastman Dental Institute, University College London , 256 Gray's Inn Road, London WC1X 8LD, U.K.
⁶ UCL Division of Surgery and Interventional Science, University College London , Royal Free Campus, Rowland Hill Street, London NW3 2PF, U.K.

Abstract

Healthcare-associated infections pose a serious risk for patients, staff, and visitors and are a severe burden on the National Health Service, costing at least £1 billion annually. Antimicrobial surfaces significantly contribute toward reducing the incidence of infections as they prevent bacterial adhesion and cause bacterial cell death. Using a simple, easily upscalable swell-encapsulation-shrink method, novel antimicrobial surfaces have been developed by incorporating metal oxide nanoparticles (NPs) and crystal violet (CV) dye into medical-grade polyurethane sheets. This study compares the bactericidal effects of polyurethane incorporating ZnO, Mg-doped ZnO, and MgO. All metal oxide NPs are well defined, with average diameters ranging from 2 to 18 nm. These materials demonstrate potent bactericidal activity when tested against clinically relevant bacteria such as Escherichia coli and Staphylococcus aureus. Additionally, these composites are tested against an epidemic strain of methicillin-resistant Staphylococcus aureus (MRSA) that is rife in hospitals throughout the UK. Furthermore, we have tested these materials using a low light intensity (∼500 lx), similar to that present in many clinical environments. The highest activity is achieved from polymer composites incorporating CV and ∼3 nm ZnO NPs, and the different performances of the metal oxides have been discussed.