Developed at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw, the coating can reportedly be applied to a wide variety of surfaces. It's said to be very chemically stable, and is able to withstand repeated washings with detergent.
The coating initially takes the form of liquid boron compounds which contain colloidal gold nanoparticles. The object to be coated is immersed in the solution, and a polymerizing agent is then added. This causes the liquid to form into a nanocomposite polymer, coating the surface of the object within about 12 minutes.
In lab tests, populations of E. coli and Staph. aureus bacteria decreased by up to 90 percent within 12 hours of exposure to the nanocomposite. Unlike some other antibacterial coatings, however, this one doesn't kill bacteria by releasing anything into their environment. Instead, the gold nanoparticles stay put, and only affect microbes that come into direct contact with them. Not only is this quality claimed to make the coating safer for people and the environment, but it should also allow it to remain effective for longer.
Additionally, the nanocomposite so far appears to be harmless to human cells. After being exposed to it for several months, four lines of human cells reportedly remained unharmed. In fact, cells even started growing on cotton wool fibers treated with it.
“Medicine is becoming more and more effective by the day. However, despite this fact, problems with bacterial infections are common in clinical practice. Patients with such complications usually require admission to hospital for up to two weeks longer than the normal patient. Not only do people suffer, but also the cost associated with hospitalization runs into thousands and millions of dollars. Dressings with our coatings could significantly reduce these problems,” said Dr. Katarzyna Wybrańska (IPC PAS).The properties of the new coatings pave the way for interesting applications. “The demand for biomedical products with proven antiseptic properties and a lack of toxicity to human cells is great. Therefore, we are thinking of using our nanocomposites in the production of hydrogel dressings. Another potential area of application is associated with the scaffolds used for cell and tissue culture,” noted Marcin Fiałkowski, professor at the IPC PAS.
Research on the coatings, carried out in cooperation with the Jagiellonian University in Cracow, was funded by a grant from the TEAM program of the Foundation for Polish Science, and work on their commercial applications currently is being developed under the IMPULS FPS program.