Since copper has long been known to destroy viruses and bacteria on contact, it is often applied by professionals to frequently touched surfaces, such as doorknobs. A new copper nanowire spray could allow ordinary people to apply the same treatment to already existing surfaces.
Ames National Laboratory from the United States Department of Energy (DOE), 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 on flexible electronic equipment.
Two different spray varieties, each with advantages and disadvantages, are being evaluated by scientists. One uses pure copper nanowire segments 60 nanometers wide (one-hundredth the width of a human hair), while the other uses copper-zinc nanowire elements of the same size.
Both versions hold the wires in a carrier solution, such as water or ethanol. The liquid produces a thin antimicrobial coating after being sprayed onto a surface material such as glass, plastic or stainless steel and allowed to cure at room temperature.
Lab tests revealed that copper discs sprayed with the coating killed the SARS CoV-2 virus (which induces Covid-19) as completely as an uncoated copper disc. However, the coating completed the task in just 20 minutes as opposed to the regular disk’s 40 due to the larger surface area offered by the nanowires.
Spraying pure copper nanowires inactivated the virus twice as fast in the first 10 minutes as its copper-zinc equivalent. The copper-zinc coating, however, required less frequent reapplication because it remained effective longer. For this reason, researchers consider it the ideal possibility of practical use. An article 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, University of Ioannina and the Leibniz Institute for Materials Engineering successfully killed tumor cells in mice using compounds from nanoscale copper as well as immunotherapy.
The research team conducted studies on lung and colon cancer. The group of physicists, biomedical researchers and chemical engineers discovered that these tumors were sensitive to copper oxide nanoparticles made of copper and oxygen.
Once inside living organisms, the nanoparticles will dissolve and become toxic. The researchers created the nanoparticles using iron oxide, allowing the team to kill cancer cells without harming healthy cells.