There’s a lot of interest in finding ways to discourage bacteria from growing on various surfaces, for example, Sharklet, which is based on nanostructures on sharkskin, is a product being developed for hospitals (my Feb. 10, 2011 posting) and there are polymers that ‘uninvite’ bacteria at the University of Nottingham (my Aug. 13, 2012 posting).
A Jan. 31, 2013 news item on Nanowerk highlights the latest work being done at Duke University,
Duke University engineers have developed a material that can be applied like paint to the hull of a ship and will literally be able to dislodge bacteria, keeping it from accumulating on the ship’s surface. This buildup on ships increases drag and reduces the energy efficiency of the vessel, as well as blocking or clogging undersea sensors.
The team’s research was published online,
Bioinspired Surfaces with Dynamic Topography for Active Control of Biofouling by Phanindhar Shivapooja, Qiming Wang, Beatriz Orihuela, Daniel Rittschof, Gabriel P. López1, Xuanhe Zhao. Advanced Materials, Article first published online: 6 JAN 2013, DOI: 10.1002/adma.201203374
Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
The article is behind a paywall but the abstract is freely available,
Dynamic change of surface area and topology of elastomers is used as a general, environmentally friendly approach for effectively detaching micro- and macro-fouling organisms adhered on the elastomer surfaces. Deformation of elastomer surfaces under electrical or pneumatic actuation can debond various biofilms and barnacles. The bio-inspired dynamic surfaces can be fabricated over large areas through simple and practical processes. This new mechanism is complementary with existing materials and methods for biofouling control.
Duke University’s Jan. 31, 2013 news release by Richard Merritt, which originated the news item, provides more detail from the researchers,
“We have developed a material that ‘wrinkles,’ or changes it surface in response to a stimulus, such as stretching or pressure or electricity,” said Duke engineer Xuanhe Zhao, assistant professor in Duke’s Pratt School of Engineering. “This deformation can effectively detach biofilms and other organisms that have accumulated on the surface.”
Zhao has already demonstrated the ability of electric current to deform, or change, the surface of polymers.
The researchers tested their approach in the laboratory with simulated seawater, as well as on barnacles. These experiments were conducted in collaboration with Daniel Rittsch of the Duke University Marine Lab in Beaufort, N.C.
Keeping bacteria from attaching to ship hulls or other submerged objects can prevent a larger cascade of events that can reduce performance or efficiency. Once they have taken up residence on a surface, bacteria often attract larger organisms, such as seaweed and larva of other marine organisms, such as worms, bivalves, barnacles or mussels.
There are other ways to introduce efficiencies in marine transp0rtation as per my June 27, 2012 posting about Zyvex Marine and its new composites which will make for lighter vessels.