Diverse Surface Properties Reveal that Substratum Roughness Affects Fungal Spore Binding

Summary Binding to surfaces by fungal spores is a prerequisite to biofilm formation. The interactions of polytetrafluoroethylene (PTFE), glass and silicon with three fungal spores, of differing shape and size (Aspergillus niger 1957, Aspergillus niger 1988 and Aureobasidium pullulans), were investigated. A multifractal analysis was conducted to give quantitative measures of density, dispersion and clustering of spores on the surfaces. The PTFE, glass and silicon surfaces presented a range of surface topographies and wettabilities. PTFE was the roughest and most non-wettable surface, whilst silicon was the opposite in terms of both latter aspects. The A. niger species were more non-wettable than A. pullulans. Overall A. niger 1957 attached in higher numbers to PTFE, whilst A. niger 1988 and A. pullulans bound in highest numbers to glass. The results from this work, demonstrated that overall substratum surface roughness influenced spore binding rather than the physicochemical or chemical properties of surfaces or spores.