Abstract

In this work, we introduce a one-step strategy that is suitable for continuous flow manufacturing of antimicrobial PDMS materials. The process is based on the intrinsic capacity of PDMS to react to certain organic solvents, which enables the incorporation of antimicrobial actives such as salicylic acid (SA), which has been approved for use in humans within pharmaceutical products. By combining different spectroscopic and imaging techniques, we show that the surface properties of PDMS remain unaffected while high doses of the SA are loaded inside the PDMS matrix. The SA can be subsequently released under physiological conditions, delivering a strong antibacterial activity. Furthermore, encapsulation of SA inside the PDMS matrix ensured a diffusion-controlled release that was tracked by spatially resolved Raman spectroscopy, Attenuated Total Reflectance IR (ATR-IR), and UV-Vis spectroscopy. The biological activity of the new material was evaluated directly at the surface and in the planktonic state against model pathogenic bacteria, combining confocal laser scanning microscopy, electron microscopy, and cell viability assays. The results showed complete planktonic inhibition for clinically relevant strains of Staphylococcus aureus and Escherichia coli, and a reduction of up to 4 orders of magnitude for viable sessile cells, demonstrating the efficacy of these surfaces in preventing the initial stages of biofilm formation. Our approach adds a new option to existing strategies for the antimicrobial functionalisation of a wide range of products such as catheters, wound dressings and in-dwelling medical devices based on PDMS.

Details

Title
One-step preparation of antimicrobial silicone materials based on PDMS and salicylic acid: insights from spatially and temporally resolved techniques
Author
Barbieri, Luca 1 ; Sorzabal Bellido Ioritz 2 ; Beckett, Alison J 3 ; Prior, Ian A 3 ; Fothergill, Jo 4 ; Diaz Fernandez Yuri A 2   VIAFID ORCID Logo  ; Raval Rasmita 2 

 University of Liverpool & National Biofilm Innovation Centre, Open Innovation Hub for Antimicrobial Surfaces, Department of Chemistry, Liverpool, UK (GRID:grid.10025.36) (ISNI:0000 0004 1936 8470); University of Liverpool, Institute of Infection and Global Health, Liverpool, UK (GRID:grid.10025.36) (ISNI:0000 0004 1936 8470) 
 University of Liverpool & National Biofilm Innovation Centre, Open Innovation Hub for Antimicrobial Surfaces, Department of Chemistry, Liverpool, UK (GRID:grid.10025.36) (ISNI:0000 0004 1936 8470) 
 University of Liverpool, Biomedical Electron Microscopy Unit, Liverpool, UK (GRID:grid.10025.36) (ISNI:0000 0004 1936 8470) 
 University of Liverpool, Institute of Infection and Global Health, Liverpool, UK (GRID:grid.10025.36) (ISNI:0000 0004 1936 8470) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20555008
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2543576620
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.