Scientists Create Slippery Technology That Prevents Bacterial Slime From Forming on Surfaces

Posted on July 30, 2012

Scientists have created a new slippery technology, named SLIPS (Slippery-Liquid-Infused Porous Surfaces), that prevents more than 99% of harmful bacterial slime from forming on surface. SLIPS was developed by a team of Harvard scientists. The scientists coated solid surfaces with an immobilized liquid film to trick the bacteria into thinking they had nowhere to attach and grow.

Joanna 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, says, "People have tried all sorts of things to deter biofilm build-up - textured surfaces, chemical coatings, and antibiotics, for example. 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."

SLIPS creates a hybrid surface that is smooth and slippery due to the liquid layer that is immobilized on it. The super-slippery surfaces have been shown to repel both water- and oil-based liquids and even prevent ice or frost from forming.

Alexander Epstein, a recent Ph.D. graduate who worked in Aizenberg's lab at the time of the study, says, "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."

Tak-Sing Wong, a researcher at SEAS and a Croucher Foundation Postdoctoral Fellow at the Wyss Institute, says, "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."

Aizenberg and her collaborators report in a study published here in the Proceedings of the National Academy of Sciences (PNAS), 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 researchers say SLIPS is also nontoxic, scalable, and self-cleaning. The say it needs "nothing more than gravity or a gentle flow of liquid to stay unsoiled."

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