Micropatterning of bacteria on two-dimensional lattice protein surface observed by atomic force microscopy

In this study, we characterized the two-dimensional lattice of bovine serum albumin (BSA) as a chemical and physical barrier against bacterial adhesion, using fluorescence microscopy and atomic force microscopy (AFM). The lattice of BSA on glass surface was fabricated by micro-contact printing (microCP), which is a useful way to pattern a wide range of molecules into microscale features on different types of substrates. The contact-mode AFM measurements showed that the average height of the printed BSA monolayer was 5-6 nm. Escherichia coli adhered rapidly on bare glass slide, while the bacterial adhesion was minimized on the lattices in the range of 1-3 microm(2). Especially, the bacterial adhesion was completely inhibited on a 1 microm(2) lattice. The results suggest that the anti-adhesion effects are due by the steric repulsion forces exerted by BSA.