Insect wings hold antimicrobial clues for improved medical implants

An E-coli bacteria lying on a bed of nano-nails Professor Bo Su, University of Bristol

Press release issued: 6 April 2020

Some insect wings such as cicada and dragonfly possess nanopillar structures that kill bacteria upon contact. However, to date, the precise mechanisms that cause bacterial death have been unknown.

Using a range of advanced imaging tools, functional assays and proteomic analyses, a study by the University of Bristol has identified new ways in which nanopillars can damage bacteria.

These important findings, published in Nature Communications, will aid the design of better antimicrobial surfaces for potential biomedical applications such as medical implants and devices that are not reliant on antibiotics.

Bo Su, Professor of Biomedical Materials at the University of Bristol’s Dental School, who authored the research said:

“In this work, we sought to better understand nanopillar-mediated bactericidal mechanisms. The current dogma is that nanopillars kill bacteria by puncturing bacterial cells, resulting in lysis. However, our study shows that the antibacterial effects of nanopillars are actually multifactorial, nanotopography- and species-dependent.

“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.

“We can now hopefully translate this expanded understanding of nanopillar-bacteria interactions into the design of improved biomaterials for use in real world applications.”

Funded by the Medical Research Council, the implications of the research are far-reaching. Prof. Su explains:

“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.

“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.”

Paper:

Antibacterial effects of nanopillar surfaces are mediated by cell impedance, penetration and induction of oxidative stress, by Professor Bo Su in Nature Communications.

Further information

Professor Bo Su, Bristol Dental School, University of Bristol

Dr Bo Su is Professor of Biomedical Materials within the Bristol Dental School at the University of Bristol. He has research experience in materials for over 30 years, including structural, functional and biomedical materials. After obtaining his PhD at the University of Birmingham in 1998, he spent five years as a post-doctoral researcher at Imperial College and Birmingham University respectively. He was awarded an EPSRC Advanced Research Fellowship in 2003. He joined Bristol as a Senior Lecturer in 2005 and was promoted to Reader in 2009 and Professor in 2013. He has published more than 140 journal papers and holds 4 patents. He has received funding from EPSRC, BBSRC, MRC, NIHR, GWR, charities and industries.

Bo is a Fellow of Institute of Materials, Mineral and Mining (FIMMM) and a member of EPSRC Peer Review College. His research interests are in materials processing and fabrication, including micro- and nano-fabrication and surface patterning of titanium metals, ceramics, polymers and composites for biomedical applications. He leads the Biomaterials Engineering Group (bioMEG) and is currently the School Postgraduate Research Director.