Combination of Bioresorbable Polyesters and Essential Oils as Innovative Antimicrobial Coating Biomaterials

The emergence of bacterial and fungal strains resistance to many important classes of drug therapy based on antibiotics means that there is an immediate and urgent need for novel solutions to address this global challenge in modern medicine. One approach being explored is the development of drug-free broad spectrum antimicrobial materials. In this regard, natural agents, for example, EOs (EOs), have attracted a great deal of attention due to their diverse bioactive components, which enable multiple concurrent antimicrobial mechanisms, overcoming the development of resistance. The challenges in this field are to select an appropriate essential oil, to develop a controlled-release delivery system, and to incorporate it to medical devices. Research in this project focused on designing biodegradable polymer systems to deliver high encapsulation efficiency and controlled release of strong antimicrobial EO for bioapplications. In this thesis, two widely available EOs, cinnamon bark oil and peppermint oil, were initially selected and analysed in terms of composition and antibacterial activity to determine the most suitable antibacterial agent. As a result, cinnamon bark oil was selected due to the potential antimicrobial activity against both Gram-negative strains, E. coli and P. aeruginosa and Gram-positive strains, S. aureus and S. epidermidis. It was also found that cinnamon oil has higher antibacterial ability against Gram-positive than against Gram-negative bacteria.