Neither smooth nor rough – Novel bio-inspired surfaces make insects slip

Insects are able to climb almost any type of surface using their specialised adhesive organs. So far, most technical solutions to control insect pests involve toxic or sticky components, which need to be frequently renewed. Scientist at the Biomimetics-Innovation-Centre Bremen and Kiel University have now developed and tested a bio-inspired new repellent technology without toxic or sticky components.

„There are a few natural surfaces which make it difficult for insects to climb and walk across“, said Dr. Elena Gorb (Kiel University). “One thing these slippery surfaces have in common is that they use combinations of different roughness. The nanostructured surfaces are not smooth enough for the adhesive pads, and not rough enough for the claws to interlock. This makes it difficult for many insects to climb.”

For the first time the groups from Bremen and Kiel have now built and tested a nanostructured insect repellent together with a swiss manufacturer of polymeric foils. A special feature of the new approach is the possibility to adapt the dimensions of the nanostructure to prevent only certain groups of insects from climbing up the surfaces. “This ability allows us to for example distinguish between pollinating and non-wanted insects. A much better and more ecological approach in comparison to the typically used “chemical maze” pesticides.” said Prof. Dr. Jan-Henning Dirks Dirks (HSB). In addition, the nanostructured polymeric foils are much more durable and can be easily used in difficult to reach appliances such as air-condition and ventilation ducts. As a next step the researchers are now trying to further improve the efficiency of their new surfaces.

Original work:

Investigating the efficiency of a bio-inspired insect repellent surface structure.
Christopher Graf, Antonia B. Kesel, Elena V. Gorb, Stanislav N. Gorb and Jan-Henning Dirks
Bioinspiration and Biomimetics (2018)

Illustration of the efficiency of the nanostructured surfaces. Even at small incline the insects notably struggle to climb up the surface.

©: Bionik-Innovations-Centrum, Hochschule Bremen, Bioinspiration and Biomimetics 2018.