Bioinspiration for battling bacteria: Nature inspired high aspect ratio nanostructures for new age antibacterial surfaces
Abstract
Bacterial colonization and biofilm formation on abiotic surfaces effectuate corrosion,
fermentation, and infection resulting in tremendous economic and human losses each year.
Aggravating the situation, new multi-drug resistant bacterial strains are emerging
continuously, aided by the artificial selection of such strains due to antibiotic overuse, and
spreading across the globe through living and non-living carriers. Deaths from drug-resistant
microbial infections are rising while approvals of new antibiotic classes have been falling for
more than a decade. Under such a scenario, the quest for alternative antibacterial strategies has
gained the utmost importance. Nanomaterials such as metal nanoparticles, graphene, and more
recently, bioinspired nanotopographies are among the most promising solutions to tackle this
problem. Almost a decade ago, it was discovered that nanopillar topography of insect wings
such as cicadas, dragonflies and damselflies can kill bacteria by physically rupturing their cell
wall as the cells try to attach to the surface. This exciting discovery meant that if such
topographies could be successfully emulated on surfaces of choice, the need for antibiotic
administration could be eliminated and development of drug-resistant strains can be curtailed.
This thesis focuses on engineering such bioinspired nanostructured surfaces to combat the
spread of bacterial infections. The first part of the work in the thesis aims to replicate various
high aspect ratio nanostructures on material surfaces, assess their bactericidal activity through
experimental measurements and understand the various aspects of the mechanobactericidal
phenomena. The second part of the thesis aims to develop technologies for affordable, and
scalable adoption of these structures.