Liquid metal coating creates effective antiviral, antimicrobial fabric

Microbes can survive on the fabric’s hospitals use for bedding, clothing and face masks for a long time. Metallic surface coatings such as Copper or Silver are an effective way to eradicate these pathogens, but many metal particle coating technologies have issues such as non-uniformity, processing complexity, or poor adhesion.

An international team of researchers has used liquid Gallium to create an antiviral and antimicrobial coating and tested it on a range of fabrics, including facemasks. The coating adhered more strongly to fabric than some conventional metal coatings, and eradicated 99% of several common pathogens within five minutes.

Researchers placed liquid Gallium into an ethanol solution and used sound waves—a process known as sonication—to create Ga nanoparticles. The nanoparticle solution was then spray coated onto the fabric and the Ga adhered to the fibres as the ethanol evaporated.

Then the researchers dipped the Ga-coated fabric into a Copper sulfate solution, creating a spontaneous galvanic replacement reaction. The reaction deposits Copper onto the fabric, creating a coating of liquid metal Copper alloy nanoparticles.

Research team were tested the fabric on five common microbes: Staphylococcus aureus, Escherichia coli, Candida albicans, human influenza and coronavirus (HCoV 229E). These microbes grow aggressively on non-coated fabrics. The Copper alloy coated fabric eradicated over 99% of the pathogens within five minutes, which was significantly more effective than control samples coated with only Copper or Silver.