In vitro efficacy of antimicrobial wafers against methicillin-resistant Staphylococcus aureus.

BACKGROUND

Lyophilized wafers have been developed as vehicles for the storage and delivery of therapeutic compounds to exuding wounds. The primary objective of this study was to incorporate a selection of antimicrobial compounds in karaya wafers and measure their efficacy against methicillin-resistant Staphylococcus aureus.

METHODS

Four antimicrobial compounds, including an antibiotic, were incorporated within karaya gels and freeze-dried to a shaped-disc form suitable for in vitro testing against methicillin-resistant S. aureus. Disc diffusion and Franz diffusion methods were used to quantify the utility and efficacy of these 'antimicrobial wafers'. Flow rheology and scanning electron microscopy were also used to aid gel and wafer characterization.

RESULTS

Lyophilized wafers swelled in simulated wound fluid and released the contained compounds with mixed effect. Povidine-iodine and chlorhexidine were most effective in protein-free buffer while the action of neomycin sulfate was enhanced by the presence of bovine serum albumin. Silver sulfadiazine was the least effective overall.