Biomaterials

Statement of the Problem: The adhesion of bacterial cells on any surface is the first step of biofilm formation. Biomedical field is more concern about biofilm formation as medical devices get frequently contaminated with bacteria and leading to the formation of mature biofilm which can put patient lives at risk. Researchers have reported that the surface topography with micro patterns affects the initial adhesion of bacterial cells. However, the effect of the number of corners on the behavior of bacterial cells is yet to be investigated. In this work, the different types of microscale geometrical features (Triangle, Square,

Star pattern with four and five corners) are fabricated on polydimethylsiloxane (PDMS) using soft lithography technique. Through static droplet contact angle analysis, it is confirmed that the fabricated micro patterns alter the wettability of plain PDMS surface. The effect of number of corners on the migration and

initial attachment of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are investigated using fluorescence microscopy. The adhesion of bacterium depends on the number of corners present in the geometrical feature.

Moreover, the bacterial adhesion is correlated with the ratio of pillar cross-sectional area to its perimeter (λ). The experimental investigation can be useful in designing the effective geometry which can be used in making anti biofouling structured polymeric devices for biomedical applications.