Imparting commercial antimicrobial dressings with low-adherence to burn wounds

Sogol Asghari; Sarvesh Logsetty; Song Liu

doi:10.1016/j.burns.2016.01.005

Imparting commercial antimicrobial dressings with low-adherence to burn wounds

Burns. 2016 Jun;42(4):877-83. doi: 10.1016/j.burns.2016.01.005. Epub 2016 Feb 1.

Authors

Sogol Asghari¹, Sarvesh Logsetty², Song Liu³

Affiliations

¹ Department of Biosystems Engineering, Faculty of Agricultural and Food Sciences, University of Manitoba, Winnipeg, MB, Canada.
² Manitoba Firefighters Burn Unit, Department of Surgery, Faculty of Medicine, University of Manitoba, Winnipeg, MB, Canada.
³ Department of Biosystems Engineering, Faculty of Agricultural and Food Sciences, University of Manitoba, Winnipeg, MB, Canada; Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada; Department of Chemistry, University of Manitoba, Winnipeg, MB, Canada. Electronic address: Song.Liu@umanitoba.ca.

PMID: 26847614
DOI: 10.1016/j.burns.2016.01.005

Abstract

The objective of our study was to decrease the wound adherence of commercial silver based wound dressings by depositing a non-adherent layer. Our hypothesis was that this non-adherent layer will lower the dressing's adherence to burn wounds without compromising the antimicrobial activity or increasing the cytotoxicity. A polyacrylamide (PAM) hydrogel layer was grafted on two commercial silver antimicrobial dressings (silver nanocrystal dressing (NC) and silver plated dressing (SP)) using a proprietary technique. The grafted PAM served as the non-adherent layer. Dressing adherence was measured with a previously published in vitro gelatin model using an Instron mechanical force testing instrument. The dressings were challenged with two clinically retrieved bacterial strains (Methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant (MDR) Pseudomonas aeruginosa) with both a disk diffusion test, and a suspension antibacterial test. The cytotoxicity of samples to human neonatal fibroblast cells was evaluated with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. Both untreated dressings showed high peeling energy: 2070±453J/m(2) (NC) and 669±68J/m(2) (SP), that decreased to 158±119J/m(2) (NC) and 155±138J/m(2) (SP) with the PAM deposition. Addition of the PAM caused no significant difference in zone of inhibition (ZOI) (disk diffusion test) or antibacterial kinetics (suspension test) against both bacteria (p>0.05, n=6) in either dressing. Survival of fibroblasts was improved by the PAM grafting from 48±5% to 60±3% viable cells in the case of NC and from 55±8% to 61±4% viable cells in SP (p<0.05, n=12). It was concluded that PAM as a non-adherent layer significantly decreases the adherence of these two commercial antimicrobial dressings in an in vitro gelatin model while preserving their antimicrobial efficacy, and reducing their cytotoxicity.

Keywords: Burn wound dressing; Hydrogel; Non-adherent dressing; Polyacrylamide; Silver dressing.

MeSH terms

Acrylic Resins / therapeutic use
Anti-Infective Agents / analysis
Anti-Infective Agents / pharmacology
Bandages, Hydrocolloid*
Burns / therapy*
Cell Survival
Cells, Cultured
Fibroblasts / pathology
Humans
Pseudomonas aeruginosa / drug effects
Silver / analysis
Silver / pharmacology
Wound Infection / prevention & control*

Substances

Acrylic Resins
Anti-Infective Agents
Silver
polyacrylamide