Reduction of Pathogen Attachment by NO-Releasing Polysaccharide-Based Hybrid Materials with Different Amine Densities

Thin-film hybrid material coatings were synthesized through a sol-gel process consisting of alginate and tetraethyl orthosilicate. By exchanging the silicate with the aminosilane N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, the ability of absorbing nitric oxide was tuned. Depending on the silicate/aminosilane ratio, different nitrogen oxide (NO)-releasing species were identified by ultraviolet-visible spectroscopy. Bacterial adhesion assays were performed using the Gram-positive bacterium B. subtilis and the Gram-negative bacteria P. fluorescens and E. coli, revealing species-specific responses induced by both surface properties and the presence of NO. The results highlight the immense potential of sustainable hybrid materials as antifouling coatings with adjustable properties, customizable polishing rates, and the potential to apply NO as a bioactive antifouling additive.