A wet-tolerant adhesive patch inspired by protuberances in suction cups of octopi

-Nature, Materials science: How to suck like an octopus-



Adhesion strategies that rely on mechanical interlocking or molecular attractions between surfaces can suffer when coming into contact with liquids. Thus far, artificial wet and dry adhesives have included hierarchical mushroom-shaped or porous structures that allow suction or capillarity, supramolecular structures comprising nanoparticles, and chemistry-based attractants that use various protein polyelectrolytes. However, it is challenging to develop adhesives that are simple to make and also perform well- and repeatedly- under both wet and dry conditions, while avoiding non-chemical contamination on the adhered surfaces.



Here Prof. Chang Hyun PANG and his team present an artificial, biologically inspired, reversible wet/dry adhesion system that is based on the dome-like protuberances found in the suction cups of octopi. To mimic the architecture of these protuberances, they use a simple, solution-based, air-trap technique that involves fabricating a patterned structure as a polymeric master, and using it to produce a reversed architecture, without any sophisticated chemical syntheses or surface modifications.



The micrometre-scale domes in our artificial adhesive enhance the suction stress. This octopus-inspired system exhibits strong, reversible, highly repeatable adhesion to silicon wafers, glass, and rough skin surfaces under various conditions (dry, moist, under water and under oil). To demonstrate a potential application, they also used our adhesive to transport a large silicon wafer in air and under water without any resulting surface contamination. Their octopus-inspired adhesives might be useful when applied over skin or a wound and so partially assist with wound healing. They note that our patches promoted wound healing less well than did 3M Tegaderm, but they are investigating stem-cell and drug-loading approaches to improve their practical utility.



Please follow the link for the published news.

https://www.nature.com/nature/journal/v546/n7658/full/546358a.html

http://gizmodo.com/octopus-inspired-materials-could-one-day-save-your-life-1796090566