Format

Send to

Choose Destination
ACS Appl Mater Interfaces. 2017 Jul 5;9(26):21631-21638. doi: 10.1021/acsami.7b03672. Epub 2017 Jun 23.

Taking the Silver Bullet Colloidal Silver Particles for the Topical Treatment of Biofilm-Related Infections.

Author information

1
Department of Surgery, Otolaryngology Head and Neck Surgery, Basil Hetzel Institute for Translational Health Research, The University of Adelaide , Adelaide, South Australia Australia.
2
Future Industries Institute, University of South Australia , Mawson Lakes, South Australia Australia.
3
School of Pharmacy and Medical Sciences, University of South Australia , Adelaide, South Australia Australia.
4
Adelaide Biofilm Test Facility, Sansom Institute for Health Research, University of South Australia , Adelaide, South Australia Australia.
5
Laboratory of Pharmaceutical Microbiology, Ghent University , Gent, Belgium.
6
ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Adelaide, South Australia Australia.

Abstract

Biofilms are aggregates of bacteria residing in a self-assembled matrix, which protects these sessile cells against external stress, including antibiotic therapies. In light of emerging multidrug-resistant bacteria, alternative strategies to antibiotics are emerging. The present study evaluated the activity of colloidal silver nanoparticles (AgNPs) of different shapes against biofilms formed by Staphylococcus aureus (SA), methicillin-resistant SA (MRSA), and Pseudomonas aeruginosa (PA). Colloidal quasi-spherical, cubic, and star-shaped AgNPs were synthesized, and their cytotoxicity on macrophages (THP-1) and bronchial epithelial cells (Nuli-1) was analyzed by the lactate dehydrogenase assay. The antibiofilm activity was assessed in vitro by the resazurin assay and in an in vivo infection model in Caenorhabditis elegans. Cubic and star-shaped AgNPs induced cytotoxicity, while quasi-spherical AgNPs were not toxic. Quasi-spherical AgNPs showed substantial antibiofilm activity in vitro with 96% (±2%), 97% (±1%), and 98% (±1%) biofilm killing of SA, MRSA, and PA, respectively, while significantly reducing mortality of infected nematodes. The in vivo antibiofilm activity was linked to the accumulation of AgNPs in the intestinal tract of C. elegans as observed by 3D X-ray tomography. Quasi-spherical AgNPs were physically stable in suspension for over 6 months with no observed loss in antibiofilm activity. While toxicity and stability limited the utilization of cubic and star-shaped AgNPs, quasi-spherical AgNPs could be rapidly synthesized, were stable and nontoxic, and showed substantial in vitro and in vivo activity against clinically relevant biofilms. Quasi-spherical AgNPs hold potential as pharmacotherapy, for example, as topical treatment for biofilm-related infections.

KEYWORDS:

MRSA; Pseudomonas aeruginosa; Staphylococcus aureus; biofilms; chemotherapy; nanoparticles; silver

PMID:
28598149
DOI:
10.1021/acsami.7b03672
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center