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.
This is an artist's illustration of a surface repelling biofilms. Credit: Phanindhar Shivapooja and Qiming Wang
The material works by physically moving at the microscopic level, knocking the bacteria away. This avoids the use of bacteria-killing paints, which can contain heavy metals or other toxic chemicals that might accumulate in the environment and unintentionally harm fish or other marine organisms.
The Duke researchers also say that similar types of materials could be used in other settings where the buildup of bacteria – known as biofilms -- presents problems, such as on the surfaces of artificial joint implants or water purification membranes.
"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."
The results of the Duke studies were published online in the journal Advanced Materials.
Zhao has already demonstrated the ability of electric current to deform, or change, the surface of polymers.
"Nature has offered many solutions to deal with this buildup of biological materials that we as engineers can try to recreate," said Gabriel López, professor of biomedical engineering and mechanical engineering and materials science. He also serves as director of Research Triangle Materials Research Science and Engineering Center (MRSEC), which is funded by the National Science Foundation.
"For example, the hair-like structures known as cilia can move foreign particles from the lungs and respiratory tract," Lopez said. "In the same manner, these types of structures are used by mollusks and corals to keep their surfaces clean. To date, however, it is been difficult to reproduce the cilia, but controlling the surface of a material could achieve the same result."
The researchers tested their approach in the laboratory with simulated seawater, as well as on barnacles. These experiments were conducted in collaboration with Daniel Rittschof 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.
"It is known that bacterial films can recruit other organisms, so stopping the accumulation process from the beginning in the first place would make a lot of sense," Lopez said.
The project is funded by the U.S. Office of Naval Research and the MRSEC. Other members of the Duke team are Phanindhar Shivapooja, Qiming Wang and Beatriz Orihuela.
Richard Merritt | EurekAlert!
Strange but true: Turning a material upside down can sometimes make it softer
20.10.2017 | Universitat Autonoma de Barcelona
Metallic nanoparticles will help to determine the percentage of volatile compounds
20.10.2017 | Lomonosov Moscow State University
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research