Since copper has long been recognized to destroy viruses and bacteria on contact, it is often professionally coated onto surfaces that are frequently touched, such as doorknobs. A new copper nanowire spray might make it possible for regular people to apply the same treatment to already-existing surfaces.
Ames National Laboratory of the US DOE (Department of Energy), Iowa State University, and the University at Buffalo have partnered to develop the technology. It advances earlier Ames research that produced copper ink for printing circuits onto flexible electronic equipment.
Two different spray varieties, each of which has advantages and disadvantages, are being evaluated by scientists. One uses segments of the pure copper nanowire 60 nanometers wide (one hundredth the width of a human hair), while the other uses elements of copper-zinc nanowire that are the same size.
Both versions hold the wires in a carrier solution, like water or ethanol. The liquid produces a thin antimicrobial coating after being sprayed over a surface material like glass, plastic, or stainless steel and left to cure at ambient temperature.
Lab testing revealed that copper discs sprayed with the coating killed the SARS CoV-2 virus (which induces Covid-19) as thoroughly as an uncoated copper disc. However, the coating completed the task in just 20 minutes as opposed to the plain disc’s 40 due to the larger surface area offered by the nanowires.
The pure copper nanowire spray inactivated the virus twice as fast within the first 10 minutes as its copper-zinc equivalent. The copper-zinc coating, however, required less frequent reapplication because it remained effective for a longer time. For this reason, the researchers consider it the ideal option for practical use. A paper on the research was published on February 21, 2022, in RSC Advances.
In 2020, we saw copper being used to kill cancer cells. An interdisciplinary team of scientists from the University of Bremen, KU Leuven, the University of Ioannina, and the Leibniz Institute of Materials Engineering successfully killed tumor cells in mice using nano-sized copper compounds along with immunotherapy.
The research team performed studies on lung and colon cancer. The group of physicists, biomedical researchers, and chemical engineers found these tumors to be sensitive to copper oxide nanoparticles consisting of copper and oxygen.
Once inside living organisms, the nanoparticles will dissolve and become toxic. The researchers created the nanoparticles using iron oxide, thus enabling the team to eliminate cancer cells without harming healthy cells.