Surface treatment makes aluminum antiviral and antibacterial
If there's one place where you don't want viruses or harmful bacteria to be present, it's in hospitals, where people are already vulnerable. A new process could help, by allowing aluminum surfaces in such buildings to kill the bugs.
Led by Prof. Prasad Yarlagadda, scientists at Australia's Queensland Institute of Technology started by exposing discs of ordinary 6063 aluminum alloy to corrosive sodium hydroxide (aka: lye) for three hours. Doing so altered the metal's smooth surface on a microscopic level, etching a series of ridges into it. The surface also became hydrophilic, meaning that it attracted water.
When viruses and bacteria (such as Pseudomonas aeruginosa and Staphylococcus aureus) were subsequently placed on the treated aluminum, they were drawn across the tiny ridges. This caused the microbes' outer membranes to sag between the ridges and rupture, killing them. Certain insects' wings neutralize bacteria in the same fashion.
Most of the bacteria were eliminated within three hours of contact, while numbers of common respiratory viruses dropped considerably within two hours. These figures were considerably better than those that were observed for plastic or smooth aluminum surfaces. In fact, even after testing that simulated the wear and tear that might occur in a hospital setting over time, the treated discs remained effective.
The scientists believe that the technology could also be applied to frequently touched surfaces in other busy public settings, such as cruise ships or airports.
A paper on the research was recently published in the journal ACS Biomaterials Science & Engineering.
Source: American Chemical Society