Robust Water-Resistant Nanotech Coating Could Benefit Future Medical Devices

At the Brookhaven National Laboratory, researchers created a strong nanoscale coating that can powerfully resist water. Like mercury droplets bouncing off a surface, the new material leaves behind no moisture or residue. The researchers tested cone-shaped nanostructures against nano-sized cylindrical pillars, and determined that the former performs substantially better at repelling water droplets. The super-hydrophobic material mimics properties of natural materials such as the leaves of lotus leaves that are able to expel dirt when exposed to water. The nano-coatings could potentially used to create nanoscale channels with self-cleaning properties for diagnostic applications for detecting DNA, proteins, or biotoxins.

These nanotech coatings are designed to mimic natural structures found in nature. For example, the surfaces of some plants like the lotus flower can trap tiny bubbles of air against their surface, allowing them to repel water.

For artificial coatings, researchers created a novel plastic that can self-assemble into thin sheets with a uniform structure. Once the plastic assembled itself into a uniform structure, researchers use several different techniques to etch out shapes onto the plastic. These etching techniques are the same ones used in the production of microchips.

Since researchers can tweak these surfaces by etching different patterns, its possible to "tune" different properties. This includes various surface features, such as the aforementioned column- or cone-based shapes of the nanostructure coating. In addition, researchers can create structures of different sizes on these surfaces.

For the superhydrophobic coating, researchers were able to determine the optimal pattern and sizing to ensure the surface could repel water.