Probing Interfacial Properties and Bio-molecular Interactions of Silica Nanoparticle-based Antifouling Coating

Biological fouling of artificial surfaces occurs through the adhesion and colonisation by microbial and macrofouling organisms. These processes are an enormous problem for many diverse industries, including potable water treatment and transport [1], biomedical devices [2] [3] and hospital surfaces [4, 5], food production [6] and maritime shipping [7] [8], resulting in substantial social and economic impacts. Existing antifouling technologies have relied on the incorporation of biocidal compounds, including heavy metals, to kill target fouling organisms. However, due to the potential impact of biocide-based coating technologies on the natural environment [9, 10], and the development of biocide resistant species, environmentally benign coatings are of great interest [11]. Among these coatings, antifouling coatings, which prevent biofouling by reducing the adhesion of microbes, has been studied and applied in different fields. In particular, hydrophilic coatings that enable surface hydration have demonstrated excellent antifouling performance, including hydrogen-bonding-rich and zwitterionic materials [12]. Extensive studies have been undertaken to elucidate the surface hydration underlying the antifouling materials, including hydration structure and forces, and effects of surface chemistries and different ions. Our recent discovery shows that a coating fabricated from silica nanoparticles (SiNP) functionalized with the hydrophilic epoxy silane, Glycidoxypropyltrimethoxysilane (GPS), has excellent antifouling performance when challenged by protein, bacteria, and fungal spore. This thesis sought to elucidate the underlying mechanisms behind the antifouling properties presented by GPS functionalized SiNP coatings...