Nanotopographies to prevent bacterial adhesion and biofilm formation
Indwelling medical devices, such as catheters, stents, dental implants, and orthopaedic prostheses, are susceptible to bacterial adhesion and frequently incur biofilm-associated infection. Biofilm-associated bacteria are significantly more difficult to treat compared to their planktonic counterparts, with some estimates of their tolerance to antibiotics to be between 102 and 103 times higher. As such, it is important that alternative solutions to combat biofilm-associated infections are developed.
A promising alternative to current antibiotics and disinfectants in combatting biofilm infections is by physically altering the nanotopography to form surfaces unfavourable to bacterial adhesion. This strategy of developing anti-adhesive surfaces takes inspiration from nature: shark skin is made up of tooth-like micro-scales that promote low drag and do not allow fouling organisms to attach to the surface. The nanotopography of the lotus leaf consists of small cone-like protuberances that result in a superhydrophobic surface. On these surfaces water droplets remain spherical and pick up bacteria and other contaminants, as they roll off. Surface topoography can even be bactericidal as in the case of the cicada wing in which sharp nanopillars pierce the bacterial membrane.
We are currently investigating a fundamental understanding of how topography can prevent bacterial adhesion and applying this to reduce hospital acquired infections.