Alginate-Based Wound Dressings Loaded with Natural Essential Oils: Physicochemical Characterisation and Antibacterial Performance

Abstract

Bacterial infections are a major challenge in wound healing, increasing complications and delaying recovery. This study developed alginate-based composite films incorporating three essential oils (EOs) - Hypericum perforatum (healing), Laurus nobilis (antibacterial) and Lavandula angustifolia (analgesic) - individually and in combinations, into a 3% sodium alginate matrix via solvent casting. Films were characterised for thickness, water solubility, swelling capacity and water vapour transmission rate (WVTR), as well as structural features (Fourier-transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM)) and antibacterial activity against Escherichia coli and Staphylococcus aureus. Essential oil incorporation enhanced moisture retention, maintained an optimal WVTR (1799-1906 g<middle dot>m-2<middle dot>day-1), and improved antibacterial activity, particularly against S. aureus (inhibition zones up to 16.3 mm). SEM analysis revealed increased surface roughness and porosity, while FTIR confirmed interactions between alginate and phenolic EO components. These results suggest that EO-loaded alginate films are promising, biocompatible wound dressings with infection-control and moist-healing capabilities, warranting further in vivo studies.