Learning anti-microbial physics from cicada

November 27, 2014
Scanning electron micrograph of B subtilis on nanowire surfaces. Note the pierced cell in the centre and the 'melted' glue-like remnants of disintegrated cells

(Phys.org) —Inspired by the wing structure of a small fly, an NPL-led research team developed nano-patterned surfaces that resist bacterial adhesion while supporting the growth of human cells.

The spread of with the emergence of 'super-bugs' that resist even 'last-resort' has prompted the World Health Organisation (WHO) to formally tackle the problem of an unwanted post-antibiotic era.

Antibiotics are chemicals that are selectively toxic to bacteria. Resistant bacteria can break down antibiotics to make them less toxic or alter the sites to which they bind to divert antibacterial action. In this light, it is becoming clear that reaching a subtle balance between antibiotics and infections is a long and perhaps never-ending journey which necessitates the search for alternative approaches.

Transplant medicine, wound healing and graft surgery have particularly strict requirements for infection-free cell and tissue growth. Encouragingly, approaches in support of this are not limited to the use of antibiotics. A notable solution is provided by an unlikely source - the cicada.

The wings of this small fly display bactericidal nanoscale pillar structures. Each of these pillars is a pike of several tens of nanometers in diameter and is separated from other pikes at regular nanometer intervals. Densely packed on the wing surfaces, these pillars arrange into nanopatterns which pierce the membranes of on contact, tearing bacteria apart.

Inspired by this example, a research team from NPL and the School of Oral and Dental Sciences at the University of Bristol engineered biocompatible surfaces exhibiting nanowire arrays. Each of these nanowires, in a similar fashion to the cicada's nanopillars, acts as a tiny spear that pierces bacterial cells causing their leakage and death. Remarkably, however, and unlike cicada wings, these substrates are also capable of guiding human cells to grow and multiply.

Ting Diu, a PhD student who worked on the project, published in NPG's Scientific Reports this month, said: "Biocompatible materials lack surface cues that can guide cells in a specific manner. The surfaces we engineered act as self-decontaminating shields that can sort out , which they support, from bacteria, which they resist. Because of these properties our rationale can be adapted for a variety of biomedical implants, anti-fouling surfaces or biosensors."

The introduced concept holds promise for clinically relevant materials by offering a physical rationale for anti-microbial action. In marked contrast to the biochemical mechanisms of antibiotics, which are subject to acquired resistance, physical mechanisms are non-specific, and cannot be reversed or altered, tackling bacterial cells as a whole.

Explore further: A possible alternative to antibiotics

More information: Scientific Reports, www.nature.com/srep/2014/14112 … /full/srep07122.html

Related Stories

A possible alternative to antibiotics

November 4, 2014

Scientists from the University of Bern have developed a novel substance for the treatment of severe bacterial infections without antibiotics, which would prevent the development of antibiotic resistance.

New method for quickly determining antibiotic resistance

November 24, 2014

Scientists from Uppsala University, the Science for Life Laboratory (SciLifeLab) in Stockholm and Uppsala University Hospital have developed a new method of rapidly identifying which bacteria are causing an infection and ...


July 22, 2013

Antimicrobial peptides are natural antibiotics found in all multicellular organisms. These molecules are viewed as potential drug candidates in the post-antibiotic era because widespread microbial resistance against them ...

Recommended for you

Atomic blasting creates new devices to measure nanoparticles

December 14, 2017

Like sandblasting at the nanometer scale, focused beams of ions ablate hard materials to form intricate three-dimensional patterns. The beams can create tiny features in the lateral dimensions—length and width, but to create ...

Engineers create plants that glow

December 13, 2017

Imagine that instead of switching on a lamp when it gets dark, you could read by the light of a glowing plant on your desk.

Faster, more accurate cancer detection using nanoparticles

December 12, 2017

Using light-emitting nanoparticles, Rutgers University-New Brunswick scientists have invented a highly effective method to detect tiny tumors and track their spread, potentially leading to earlier cancer detection and more ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.