Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New coating evicts biofilms for good

31.07.2012
Slippery technology shown to prevent more than 99 percent of harmful bacterial slime from forming on surfaces

Biofilms may no longer have any solid ground upon which to stand.

A team of Harvard scientists has developed a slick way to prevent the troublesome bacterial communities from ever forming on a surface. Biofilms stick to just about everything, from copper pipes to steel ship hulls to glass catheters. The slimy coatings are more than just a nuisance, resulting in decreased energy efficiency, contamination of water and food supplies, and—especially in medical settings—persistent infections. Even cavities in teeth are the unwelcome result of bacterial colonies.

In a study published in the Proceedings of the National Academy of Sciences (PNAS), lead coauthors Joanna Aizenberg, Alexander Epstein, and Tak-Sing Wong coated solid surfaces with an immobilized liquid film to trick the bacteria into thinking they had nowhere to attach and grow.

"People have tried all sorts of things to deter biofilm build-up—textured surfaces, chemical coatings, and antibiotics, for example," says Aizenberg, Amy Smith Berylson Professor of Materials Science at the Harvard School of Engineering and Applied Sciences (SEAS) and a Core Faculty Member at the Wyss Institute for Biologically Inspired Engineering at Harvard. "In all those cases, the solutions are short-lived at best. The surface treatments wear off, become covered with dirt, or the bacteria even deposit their own coatings on top of the coating intended to prevent them. In the end, bacteria manage to settle and grow on just about any solid surface we can come up with."

Taking a completely different approach, the researchers used their recently developed technology, dubbed SLIPS (Slippery-Liquid-Infused Porous Surfaces) to effectively create a hybrid surface that is smooth and slippery due to the liquid layer that is immobilized on it.

First described in the September 22, 2011, issue of the journal Nature, the super-slippery surfaces have been shown to repel both water- and oil-based liquids and even prevent ice or frost from forming.

"By creating a liquid-infused structured surface, we deprive bacteria of the static interface they need to get a grip and grow together into biofilms," says Epstein, a recent Ph.D. graduate who worked in Aizenberg's lab at the time of the study.

"In essence, we turned a once bacteria-friendly solid surface into a liquid one. As a result, biofilms cannot cling to the material, and even if they do form, they easily 'slip' off under mild flow conditions," adds Wong, a researcher at SEAS and a Croucher Foundation Postdoctoral Fellow at the Wyss Institute.

Aizenberg and her collaborators reported that SLIPS reduced by 96% the formation of three of the most notorious, disease-causing biofilms—Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus—over a 7-day period.

The technology works in both a static environment and under flow, or natural conditions, making it ideally suited for coating implanted medical devices that interact with bodily fluids. The coated surfaces can also combat bacterial growth in environments with extreme pH levels, intense ultraviolet light, and high salinity.

SLIPS is also nontoxic, readily scalable, and—most importantly—self-cleaning, needing nothing more than gravity or a gentle flow of liquid to stay unsoiled. As previously demonstrated with a wide variety of liquids and solids, including blood, oil, and ice, everything seems to slip off surfaces treated with the technology.

To date, this may be the first successful test of a nontoxic synthetic surface that can almost completely prevent the formation of biofilms over an extended period of time. The approach may find application in medical, industrial, and consumer products and settings.

In future studies, the researchers aim to better understand the mechanisms involved in preventing biofilms. In particular, they are interested in whether any bacteria transiently attach to the interface and then slip off, if they just float above the surface, or if any individuals can remain loosely attached.

"Biofilms have been amazing at outsmarting us. And even when we can attack them, we often make the situation worse with toxins or chemicals. With some very cool, nature-inspired design tricks we are excited about the possibility that biofilms may have finally met their match," concludes Aizenberg.

Aizenberg and Epstein's coauthors included Rebecca A. Belisle, research fellow at SEAS, and Emily Marie Boggs '13, an undergraduate biomedical engineering concentrator at Harvard College. The authors acknowledge support from the Department of Defense Office of Naval Research; the Croucher Foundation; and the Wyss Institute for Biologically Inspired Engineering at Harvard University.

Michael Patrick Rutter | EurekAlert!
Further information:
http://www.harvard.edu

More articles from Materials Sciences:

nachricht Serendipity uncovers borophene's potential
23.02.2017 | Northwestern University

nachricht Switched-on DNA
20.02.2017 | Arizona State 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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>