Laser-induced Graphene has been shown to inactivate over 100 percent of two human coronaviruses when the initial laboratory tests conducted in China, scientists say. The researchers from the City University of Hong Kong (CityU) planned to conduct tests with SARS-CoV-2 viruses that cause COVID-19, in the future.
According to a research published in the journal ACS Nano, it is said that these masks are easily produced at low cost, and can help to resolve the problems of sourcing the raw materials and will help in disposing of non-biodegradable masks. Also, the researchers described its production of laser-induced graphene as a “green technique and said, “All carbon-containing materials, such as cellulose or paper, can be converted into graphene using this technique”
They developed Graphene masks with an anti-bacterial efficiency of 80 percent, which the researcher said it can be enhanced to almost 100 percent with exposure to sunlight for around 10 minutes. They added, that “the conversion can be carried out under ambient conditions without using chemicals other than the raw materials, nor causing pollution”. Laser-induced graphene masks are reusable they reviewed.
The CityU Assistant professor, Ye Ruquan said, “Laser-induced graphene masks are reusable. If biomaterials are used for producing graphene, it can help to resolve the problem of sourcing raw material for masks”
The face masks have become an important tool in fighting against the COVID-19 pandemic. The most commonly used are the surgical masks that are not anti-bacterial. Therefore the researchers say that this may lead to the risk of secondary transmission of bacterial infection when people touch the contaminated surfaces of the used masks or discard them improperly.
The team also tested their laser-induced graphene with E. coli, and as result, it achieved high anti-bacterial efficiency of about 82 percent. Hence, Graphene is known for its anti-bacterial properties, so as early as last September, before the outbreak of COVID-19, researchers led by Ruquan, started working on masks with laser-induced graphene.
The researchers also said, in comparison to the anti-bacterial efficiency of activated carbon fiber and melt-blown fabrics, both are commonly-used materials in masks, which was only 2 percent and 9 percent respectively. Where, the experiment results also showed that over 90 percent of the E. coli deposited on them remained alive even after 8 hours, while most of the E. coli deposited on the graphene surface were dead after 8 hours.
Ye said that more research on the exact mechanism of graphene’s bacteria-killing property is needed. However, he believed that it might be related to the damage of bacterial cell membranes by graphene’s sharp edge, and the bacteria may be killed by dehydration induced by the water-repelling property of graphene.
The Laser-Induced graphene also showed a superior anti-bacterial capacity for aerosolised bacteria. And the team is currently working with laboratories in China to test the graphene material with two species of human coronaviruses