Effective Antibacterial Nanotextured Surfaces Based on Extreme Wettability and Bacteriophage Seeding

A method based on nanosecond laser treatment was used to design superhydrophobic and superhydrophilic aluminum alloy substrates showing enhanced cytotoxic activity with respect to Escherichia coli K12 C600 strain. It was shown that the survival of cells adhered to the superhydrophobic substrates was significantly affected by the presence of organic contaminants, which are ubiquitous in hospital practice and the food industry. The peculiarities of the texture also played a notable role in antibactericidal activity. It was found that the superhydrophilic surfaces had much higher toxicity than the superhydrophobic ones, which was explained by the mechanisms of adhesion of cells to the surface. Scanning electron microscopy and tomographic reconstruction of the adhered cells were used to study the variation of cell morphology after attachment to surfaces with different wettability. It was shown that the cytotoxicity of superhydrophobic surfaces could be significantly enhanced by using the combined antimicrobial action of bacteriophages and the superhydrophobicity of the objects.