The Design, Characterization and Antibacterial Activity of Heat and Silver Crosslinked Poly(Vinyl Alcohol) Hydrogel Forming Dressings Containing Silver Nanoparticles.

John Jackson,Helen Burt,Dirk Lange,Robin Evans,In Whang,David Plackett

doi:10.3390/nano11010096

Abstract

The prompt treatment of burn wounds is essential but can be challenging in remote parts of Africa, where burns from open fires are a constant hazard for children and suitable medical care may be far away. Consequently, there is an unmet need for an economical burn wound dressing with a sustained antimicrobial activity that might be manufactured locally at low cost. This study describes and characterizes the novel preparation of a silver nitrate-loaded/poly(vinyl alcohol) (PVA) film. Using controlled heating cycles, films may be crosslinked with in situ silver nanoparticle production using only a low heat oven and little technical expertise. Our research demonstrated that heat-curing of PVA/silver nitrate films converted the silver to nanoparticles. These films swelled in water to form a robust, wound-compatible hydrogel which exhibited controlled release of the antibacterial silver nanoparticles. An optimal formulation was obtained using 5% (w/w) silver nitrate in PVA membrane films that had been heated at 140 °C for 90 min. Physical and chemical characterization of such films was complemented by in vitro studies that confirmed the effective antibacterial activity of the released silver nanoparticles against both gram positive and negative bacteria. Overall, these findings provide economical and simple methods to manufacture stable, hydrogel forming wound dressings that release antibiotic silver over prolonged periods suitable for emergency use in remote locations.

Highlights

Traumatic burn wounds resulting from accidents associated with open fires used for heating and cooking are common in the rural areas of African countries
The films that had only been dried and the films dried and heat cured at 80 ◦ C for 90 min dissolved rapidly in water; the films heat cured at 110 ◦ C for 90 min were only partly dissolved after one week and the films heat cured at 140 ◦ C for 90 min appeared to remain intact
Supernatants collected from incubation of poly(vinyl alcohol) (PVA)/silver films over a 10-day period. Whilst these studies used bacteria growing in planktonic conditions it is possible that The in wounds and burns, left for extended periods of more than a few days, that the use of silver as an antimicrobial additive in commercially available wound dressings is well established in western countries and, amongst these dressings, there are products such as ActicoatTM 7 and ActicoatTM Moisture Control, which contain nanocrystalline silver and rely on silver nanoparticles for their anti-infective activity

Summary

Introduction

Traumatic burn wounds resulting from accidents associated with open fires used for heating and cooking are common in the rural areas of African countries. We initiated a research project aimed at developing a package or kit that could be used for immediate treatment of burn wounds in remote African communities. Such kits might contain a dressing, a pictorial instruction manual for application of the dressing, a bottle of rehydration salts, and cell phone numbers for clinics or nurses. These kits might provide an important window of opportunity for the injured person to access proper hospital care before serious infection or abnormal healing might occur

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