Thiol-capped gold nanoparticles swell-encapsulated into polyurethane as powerful antibacterial surfaces under dark and light conditions

Macdonald, T. J. et al. (2016) Thiol-capped gold nanoparticles swell-encapsulated into polyurethane as powerful antibacterial surfaces under dark and light conditions. Scientific Reports, 6, 39272. (doi: 10.1038/srep39272) (PMID:27982122) (PMCID:PMC5159832)

Abstract

A simple procedure to develop antibacterial surfaces using thiol-capped gold nanoparticles (AuNPs) is shown, which effectively kill bacteria under dark and light conditions. The effect of AuNP size and concentration on photo-activated antibacterial surfaces is reported and we show significant size effects, as well as bactericidal activity with crystal violet (CV) coated polyurethane. These materials have been proven to be powerful antibacterial surfaces against both Gram-positive and Gram-negative bacteria. AuNPs of 2, 3 or 5 nm diameter were swell-encapsulated into PU before a coating of CV was applied (known as PU-AuNPs-CV). The antibacterial activity of PU-AuNPs-CV samples was tested against Staphylococcus aureus and Escherichia coli as representative Gram-positive and Gram-negative bacteria under dark and light conditions. All light conditions in this study simulated a typical white-light hospital environment. This work demonstrates that the antibacterial activity of PU-AuNPs-CV samples and the synergistic enhancement of photoactivity of triarylmethane type dyes is highly dependent on nanoparticle size and concentration. The most powerful PU-AuNPs-CV antibacterial surfaces were achieved using 1.0 mg mL−1 swell encapsulation concentrations of 2 nm AuNPs. After two hours, Gram-positive and Gram-negative bacteria were reduced to below the detection limit (>4 log) under dark and light conditions.

• Item Type: Articles
• Additional Information: The authors thank the EPSRC for financial support (EP/M015157/1). All authors would like to thank the MaFuMa team with a special thanks to Prof. Peter Dobson. W.J.P acknowledges an EPSRC Doctoral Prize Fellowship (EP/ M506448/1).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Peveler, Dr William
• Authors: Macdonald, T. J., Wu, K., Sehmi, S. K., Noimark, S., Peveler, W. J., du Toit, H., Voelcker, N. H., Allan, E., MacRobert, A. J., Gavriilidis, A., and Parkin, I. P.
• College/School: College of Science and Engineering > School of Engineering > Biomedical Engineering
• Journal Name: Scientific Reports
• Publisher: Nature Research
• ISSN: 2045-2322
• ISSN (Online): 2045-2322
• Copyright Holders: Copyright © 2016 The Authors
• First Published: First published in Scientific Reports 6: 39272
• Publisher Policy: Reproduced under a Creative Commons License