Harvard-created coating keeps bacterial biofilms from forming on surfaces
By Ben Coxworth
August 1, 2012
Last June, scientists from Harvard University announced the development of their new SLIPS (Slippery Liquid-Infused Porous Surfaces) technology. When used to coat surfaces, it is highly effective at keeping ice, frost, or just about any type of liquid from accumulating on them. Now, it turns out that SLIPS is also very good at keeping something else from getting a toehold – biofilms.
A biofilm is a slimy layer of organic material, that is formed by bacteria on a wide variety of solid surfaces. Once a biofilm is established, it serves as a habitat for those bacteria – or other microorganisms – allowing them to flourish.
Among other things, biofilms can cause water contamination when they form on the inside of pipes, they let troublesome creatures such as barnacles make themselves at home on ships’ hulls, and they can become the source of infections when they form on medical equipment.
SLIPS apparently fools the initial biofilm-forming bacteria into thinking that stable, solid surfaces are actually liquid, thus keeping them from sticking around. This is due to the fact that SLIPS incorporates nanostructures that wick a chemically-inert, high-density liquid up to its surface. The liquid is immobilized there, creating an ultra-slippery, non-toxic coating that repels ... well, just about anything.
In lab tests, it was found that when SLIPS was added to surfaces, it decreased disease-causing Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus bacterial biofilms by 96 to 99 percent over seven days. Any biofilms that did form slipped off easily when subjected to a mild liquid flow. Additionally, SLIPS was found to work in this fashion even when subjected to ultraviolet light, high pH levels, and high salinity.
It is now hoped that the technology can find use in medical, industrial, and consumer applications.
A paper on the research was recently published in the Proceedings of the National Academy of Sciences.
Source: Harvard University