Development of willow bark derived antibacterial wound dressing

Abstract

Chronic wounds pose a challenge especially among areas with precarious healthcare systems and where the population do not have access to information about the severity of risks involved with untreated chronic wounds. When left untreated, chronic wounds may result in cellulitis, venous eczema, gangrene, haemorrhage, and limb amputation. Care and management of chronic wounds are important factors; however, antibiotic treatment is often responsible for antibiotic resistant bacteria and for this reason, antibacterial wound dressings play an important role in minimizing the risks associated with bacterial infections. Therefore, the main aim of this thesis was to use product development tools to develop a concept of a bio-based antibacterial wound dressing that can be customized by the user, so that the product can be applied to a variety of wound shapes and sizes. Willow bark was the chosen material because it is considered eco-friendly and sustainable. However, due to the coarseness nature of willow bark fiber, it cannot be the only material for producing a wound dressing, therefore, it was roving blended in a variety of proportions with Tencel and tested against two strains of Staphylococcus aureus isolated from human wound, in which one of the strains has multiple antibiotic resistances. According to the results, the blend containing 10% of willow bark fiber did not present strong antibacterial properties. However, when willow bark fiber amount was increased to 30%, it demonstrated strong antibacterial properties against the two bacterial strains tested. Furthermore, the antibacterial studies revealed that lignin and colorants play an important role in the antibacterial performance of willow bark. This thesis was part of a study conducted by Aalto University and the University of Helsinki, funded by Biocolour to evaluate the potential of willow bark as a dressing material and to determine whether the antibacterial properties of willow bark originate from its natural colorants.