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Controlled delivery of antimicrobial gallium ions from phosphate-based glasses

Valappil, S.P., Ready, D., Abou Neel, E.A., Pickup, D.M., O'Dell, L.A., Chrzanowski, W., Pratten, J., Newport, Robert J., Smith, M.E., Wilson, M., and others. (2009) Controlled delivery of antimicrobial gallium ions from phosphate-based glasses. Acta Biomaterialia, 5 (4). pp. 1198-1210. ISSN 1742-7061. (doi:10.1016/j.actbio.2008.09.019) (KAR id:47141)

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Gallium-doped phosphate-based glasses (PBGs) have been recently shown to have antibacterial activity. However, the delivery of gallium ions from these glasses can be improved by altering the calcium ion concentration to control the degradation rate of the glasses. In the present study, the effect of increasing calcium content in novel gallium (Ga2O3)-doped PBGs on the susceptibility of Pseudomonas aeruginosa is examined. The lack of new antibiotics in development makes gallium-doped PBG potentially a highly promising new therapeutic agent. The results show that an increase in calcium content (14, 15 and 16 mol.% CaO) cause a decrease in degradation rate (17.6, 13.5 and 7.3 μg mm−2 h−1), gallium ion release and antimicrobial activity against planktonic P. aeruginosa. The most potent glass composition (containing 14 mol.% CaO) was then evaluated for its ability to prevent the growth of biofilms of P. aeruginosa. Gallium release was found to reduce biofilm growth of P. aeruginosa with a maximum effect (0.86 log10 CFU reduction compared to Ga2O3-free glasses) after 48 h. Analysis of the biofilms by confocal microscopy confirmed the anti-biofilm effect of these glasses as it showed both viable and non-viable bacteria on the glass surface. Results of the solubility and ion release studies show that this glass system is suitable for controlled delivery of Ga3+. 71Ga NMR and Ga K-edge XANES measurements indicate that the gallium is octahedrally coordinated by oxygen atoms in all samples. The results presented here suggest that PBGs may be useful in controlled drug delivery applications, to deliver gallium ions in order to prevent infections due to P. aeruginosa biofilms.

Item Type: Article
DOI/Identification number: 10.1016/j.actbio.2008.09.019
Additional information: Unmapped bibliographic data: LA - English [Field not mapped to EPrints] J2 - Acta Biomater. [Field not mapped to EPrints] C2 - 18974026 [Field not mapped to EPrints] AD - Division of Biomaterials and Tissue Engineering, University College London, Eastman Dental Institute, 256 Gray's Inn Road, London, United Kingdom [Field not mapped to EPrints] AD - Division of Microbial Diseases, University College London, Eastman Dental Institute, 256 Gray's Inn Road, London, United Kingdom [Field not mapped to EPrints] AD - Microbiology, Eastman Dental Hospital, UCLH NHS Foundation Trust, 256 Gray's Inn Road, London, United Kingdom [Field not mapped to EPrints] AD - School of Physical Sciences, University of Kent, Canterbury, CT2 7NH, United Kingdom [Field not mapped to EPrints] AD - Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom [Field not mapped to EPrints] DB - Scopus [Field not mapped to EPrints]
Uncontrolled keywords: Antimicrobial, Biofilm, Drug delivery, Glass, Microbiology, calcium ion, gallium, glass, phosphate, antibiotic sensitivity, antimicrobial activity, article, bacterial viability, biofilm, colony forming unit, confocal microscopy, controlled drug release, controlled study, degradation, drug delivery system, drug solubility, growth inhibition, nonhuman, nuclear magnetic resonance, priority journal, Pseudomonas aeruginosa, Pseudomonas infection, Anti-Infective Agents, Biofilms, Cations, Gallium, Glass, Hydrogen-Ion Concentration, Magnetic Resonance Spectroscopy, Microscopy, Confocal, Phosphates, Pseudomonas aeruginosa, Temperature, Pseudomonas aeruginosa
Subjects: Q Science > QC Physics > QC173.45 Condensed Matter
Q Science > QD Chemistry > QD478 Solid State Chemistry
Divisions: Divisions > Division of Natural Sciences > Physics and Astronomy
Depositing User: Giles Tarver
Date Deposited: 16 Feb 2015 16:21 UTC
Last Modified: 16 Nov 2021 10:19 UTC
Resource URI: (The current URI for this page, for reference purposes)
Newport, Robert J.:
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