Bioinspired anti-bacterial coating for stainless steel surfaces

Numerous chemical methods today already enable addition of durable antibacterial properties on surfaces, however, only a few prove to be useful on an industrial scale. Researchers from the University of Liege (ULg), Belgium, recently presented their latest results in a project related to the development of a sustainable way to apply wide spectrum antibacterial properties onto stainless steel surfaces.

These surfaces are everywhere around us, and they are used in places where fight against bacteria is of great importance. Aside nosocomial infections which can be gained in hospital environments, the restaurants and cafes are the next in line for public health safety since they tend to have stainless steel supply and equipment.

After signing their strategic partnership in 2004, Arcelor (now ArcelorMittal) and ULg started the Biocoat project – a project where they combined their expertise to use bio-inspiration and the chemistry of synthetic polymers to devise a process where they could produce a cost-effective and environmentally friendly way to coat stainless steel surfaces with antibacterial coating.

In 2009 they demonstrated the feasibility of a process based on an aqueous solution of a bio-inspired multi-functional polymer. However, the durability of the antibacterial property was not guaranteed and the process required dozens of successive deposits of these nanometer thin layers on the steel, thus making the process unsuitable for use mass production.

“We wanted to simplify this process by using the same basic products but by changing the ways in which they were deposited”, said Christophe Detrembleur, a Senior FNRS Researcher at the ULg’s Center for Education and Research on Macromolecules (CERM). “We pre-assembled the active principles (hydrosoluble polymers bio-inspired for adhesion and nanoparticles of antibacterial silver) in the water in order to have a solution ready for use available, in other words ready to be deposited on the steel by a simple soaking or spraying.”

Aside making the process faster, less costly and effective, the researchers managed to improve it to function in water at room temperature. The solution enables the biomolecules such as anti-biofilm enzymes or antibacterial peptide to be added to the mix.

Although the researchers from ULg developed this coating with stainless steel surfaces in their mind, the promising results made them test their coating on other surfaces such as titanium, plastics and textiles.

For more information, read the paper published in the Langmuir: “Antibacterial Polyelectrolyte Micelles for Coating Stainless Steel”.