Copper Nanoparticle–Graphene Composite-Based Transparent Surface Coating with Antiviral Activity against Influenza Virus

Respiratory infections by RNA viruses are one of the major burdens on global health and economy. Viruses like influenza or coronaviruses can be transmitted through respiratory droplets or contaminated surfaces. An effective antiviral coating can decrease the viability of the virus particles in our surroundings significantly, hence reducing their transmission rate. Here, we have screened a series of nanoparticles and their composites for antiviral activity using a nanoluciferase-based highly sensitive influenza A reporter virus. We have identified copper–graphene (Cu–Gr) nanocomposite as a material with strong antiviral activity. Extensive material and biological characterization of the nanocomposite suggested a unique metal oxide-embedded graphene sheet architecture that can inactivate the virion particles within 30 min of preincubation and subsequently interferes with the entry of these virion particles into the host cell. This ultimately results in reduced viral gene expression, replication and production of progeny virus particles, and thereby slowing down of the overall pace of progression of infection. Using poly(vinyl alcohol) (PVA) as a capping agent, we have been able to generate a Cu–Gr nanocomposite-based highly transparent coating that retains its original antiviral activity in the solid form and hence can be potentially implemented on a wide variety of surfaces to minimize the transmission of respiratory virus infections.