Viral Inactivation Using Visible to UV Upconversion Nanomaterials and Application in Self-Cleaning Anti-Viral Nanofilms on Personal Protective Equipment (PPE) to Mitigate Coronavirus Spread

Abstract

COVID-19 has become one of the deadliest pandemics in human history and has taken a tremendous toll on human life in large part due to its ability to transmit through the air and from surface to surface. We developed a novel conformal nano-coating on PPE surfaces intended to capture and kill (inactivate) COVID-19 viruses on PPE surfaces. Disinfection and Sterilization has long been done using UV radiation. Taking inspiration from this conventional method, we came up with a product that can produce UV radiation locally and regeneratively, a visible to UV Upconversion Nanomaterial (UCNP). The idea here is to expose viruses to localized UV radiation (within the mutagenic range) to kill or deactivate them. In our work, we developed a Yttrium Orthosilicate-based UCNP. These nanoparticles were coated on PPE surfaces and cationic and anionic polymers using the layer by layer (LBL) coating method. An oligosaccharide species, chosen to possess strong bond affinity/complementarity to novel coronavirus S glycoprotein, was grafted to the polymer using functional groups/sites via click chemistry to add one more mechanism of virus inactivation. In our testing, two formulations, Y2SiO5(1% Pr, 1% Gd) and Y2SiO5 (1.2% Pr, 1.2% Gd, 7.2% Li) have reduced active coronavirus viral load 4*104 to 0 in an hour of exposure to white light.