Microstructuring and Biofunctionalization of Alumina Surfaces to Enhance Abrasion Resistance and Suppress Bacterial Biofilm Growth

The design and fabrication of alumina microstructured surfaces that simultaneously present high mechanical and chemical features and do not suffer biofouling are here reported. An aerosol based patterning technique was employed to fabricate alumina microstructures directly on alumina surfaces with the aim to enhance wear and chemical resistance. Microstructured alumina surfaces were subsequently biofunctionalised with antibacterial biomolecules to inhibit bacterial adhesion. Lysozyme, an antibacterial enzyme commonly found in body secretions, was used as antibacterial agent and directly deposited onto microstructured alumina surfaces. Lysozyme-biofunctionalised microstructured alumina surfaces were tested at flow condition using abrasive particles and viable bacteria. The very preliminary results showed that alumina microstructures presented high resistance against mechanical abrasion and that bacterial biofilm formation could be suppressed. In particular alumina microstructures protected lysozyme molecules from desorption and loss of enzymatic activity. Such biofunctionalised microstructures present a promising system for fundamental research in the field of biomolecule adsorption on surfaces and maybe a feasible alternative e. g. to protect surfaces of water transport systems where abrasive particles and microorganisms are present.