In the Nano Cicada Wing Argovia project, scientists from the Department of Physics at the University of Basel, the School of Life Sciences at the FHNW, and the company DSM in Kaiseraugst are exploring an innovative method of adding bactericidal properties to surfaces without using antimicrobially active substances. In doing so, the researchers are following nature’s example by recreating the structure of cicada wings, which – based on a purely mechanical principle – possess bactericidal properties. They are covered with tiny, nanometer-sized columnar structures that make the wings highly water-repellent. However, bacteria adhere extremely well to the nanocolumns – so well that their cell membranes stretch when the column moves and ultimately break, causing the bacteria to die. The bactericidal effect is based on a purely mechanical principle and not on bactericidal substances or substances with an antibiotic effect. It is hoped that resistance to this mechanical principle will form at a slower pace.

Bactericidal synthetic surfaces with broad application

Having already succeeded in emulating this principle on silicon and titanium surfaces, the researchers in the Nano Cicada Wing project want to apply the results to synthetic surfaces too, because the spectrum of potential applications is much larger. The team – including project leader Professor Ernst Meyer, Dr. Thilo Glatzel, Dr. Marcin Kisiel (University of Basel), Dr. Joachim Köser (FHNW) and Dr. Hubert Hug (DSM) – will then begin by producing polymers with various nanostructured surfaces similar to a cicada wing. The surface will also be subjected to different chemical treatments to boost the effect. The scientists will then address the activity of the bacteria and their biomechanical characterization based on atomic force microscopic investigations. If the project is completed successfully, it could open the door to numerous applications – from medical products such as catheters, which will be populated by significantly fewer bacteria, through to bactericidal foodstuffs packaging, in which food will last longer.