While some insects such as cicadas and dragonflies are known to kill bacteria that touch ‘nanopillar structures’ on their wings, the precise mechanisms were previously unknown. A team at the University of Bristol used a range of advanced imaging tools and experimental techniques to identify ways in which nanopillars can damage bacteria.
The researchers, led by professor of biomedical materials Bo Su, said the “important” findings will aid the design of better antimicrobial surfaces for potential biomedical applications such as medical implants and devices that are not reliant on antibiotics.
“Now we understand the mechanisms by which nanopillars damage bacteria, the next step is to apply this knowledge to the rational design and fabrication of nanopatterned surfaces with enhanced antimicrobial properties,” said Su.
“Additionally, we will investigate the human stem cell response to these nanopillars, so as to develop truly cell-instructive implants that not only prevent bacterial infection but also facilitate tissue integration.”
Scientists previously believed that nanopillars kill bacteria by puncturing the cells, causing them to disintegrate. However the new study showed that antibacterial effects of nanopillars come from a range of factors, and are dependent on species and the ‘nanotopography’ of wings.
“Alongside deformation and subsequent penetration of the bacterial cell envelope by nanopillars, particularly for Gram-negative bacteria, we found the key to the antibacterial properties of these nanopillars might also be the cumulative effects of physical impedance and induction of oxidative stress,” said Su.
“We can now hopefully translate this expanded understanding of nanopillar-bacteria interactions into the design of improved biomaterials for use in real world applications.”
The research, which was funded by the Medical Research Council, was published in Nature Communications.
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