Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Not Slippery When Wet: Geckos Adhere to Surfaces Submerged Underwater

11.04.2013
University of Akron study may help inform future bio-inspired gecko-like adhesives

Geckos are known for their sticky adhesive toes that allow them to stick to, climb on, and run along surfaces in any orientation--even upside down! But until recently, it was not well understood how geckos kept their sticking ability even on wet surfaces, as are common in the tropical regions in which most geckos live.


A tokay gecko (Gekko gecko) sits on a wet surface prior to adhesion tests. Geckos were pulled horizontally using a small pelvic harness (blue ribbon) attached to a motorized force sensor where the maximum force a gecko could cling was measured.

Credit: Ethan Knapp and Alyssa Stark, The University of Akron


A tokay gecko (Gekko gecko) clings to leaf stem wet with water droplets.
Credit: Alyssa Stark, The University of Akron

A 2012 study in which geckos slipped on wet glass perplexed scientists trying to unlock the key to gecko adhesion in climates with plentiful rain and moisture.

A study supported by the National Science Foundation and published in the Proceedings of the National Academy of Sciences this week solves the mystery, showing that wet, water-repellant surfaces, like those of leaves and tree trunks, actually secure a gecko's grip in a manner similar to dry surfaces.

Researchers from the University of Akron, led by integrated bioscience doctoral candidate Alyssa Stark, tested geckos on four different surfaces. The surfaces ranged from hydrophilic--those that liquids spread across when wet, like glass--to hydrophobic--water-repellent surfaces on which liquids bead, like the natural leaves geckos walk on--and intermediate ones, like acrylic sheets. Geckos were tested on these surfaces both when the surfaces were dry and when they were submerged underwater, and water completely covered the gecko's feet.

Fitting a small harness around the pelvis, geckos were gently pulled along the substrate until their feet began to slip. At this point the maximum force with which a gecko could stick was measured. On wet glass geckos slipped and could not maintain adhesion. However when tested on more hydrophobic surfaces, geckos stuck just as well to the wet surface as they did to the dry ones. When tested, geckos stuck even better to wet Teflon than dry.

To understand these findings, researchers developed a model that explains the results from the gecko study and may also help inform future bio-inspired gecko-like adhesives that can maintain adhesion underwater.

For more details, see: Geckos keep firm grip in wet natural habitat.

Media Contacts
Bobbie Mixon, NSF (703) 292-8070 bmixon@nsf.gov
Denise Henry, University of Akron henryd@uakron.edu
Lisa-Joy Zgorski, NSF (703) 292-8311 lisajoy@nsf.gov
Program Contacts
Andrew J. Lovinger, NSF (703) 292-4933 alovinge@nsf.gov
The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2012, its budget was $7.0 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.

Bobbie Mixon | EurekAlert!
Further information:
http://www.nsf.gov

More articles from Materials Sciences:

nachricht An innovative high-performance material: biofibers made from green lacewing silk
20.01.2017 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

nachricht Treated carbon pulls radioactive elements from water
20.01.2017 | Rice University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>