Performance study of a sterilization box using a combination of heat and ultraviolet light irradiation for the prevention of COVID-19

SARS-CoV-2 virus and other pathogenic microbes are transmitted to the environment through contacting surfaces, which need to be sterilized for the prevention of COVID-19 and related diseases. In this study, a prototype of a cost-effective sterilization box is developed to disinfect small items. The box utilizes ultra violet (UV) radiation with heat. For performance assessment, two studies were performed. First, IgG (glycoprotein, a model protein similar to that of spike glycoprotein of SARS-COV-2) was incubated under UV and heat sterilization. An incubation with UV at 70 degrees C for 15 min was found to be effective in unfolding and aggregation of the protein. At optimized condition, the hydrodynamic size of the protein increased to similar to 171 nm from similar to 5 nm of the native protein. Similarly, the OD280 values also increased from 0.17 to 0.78 indicating the exposure of more aromatic moieties and unfolding of the protein. The unfolding and aggregation of the protein were further confirmed by the intrinsic fluorescence measurement and FTIR studies, showing a 70% increase in the beta-sheets and a 22% decrease in the alpha-helixes of the protein. The designed box was effective in damaging the protein's native structure indicating the effective inactivation of the SARS-COV-2. Furthermore, the incubation at 70 degrees C for 15 min inside the chamber resulted in 100% antibacterial efficacy for the clinically relevant E.coli bacteria as well as for bacteria collected from daily use items. It is the first detailed performance study on the efficacy of using UV irradiation and heat together for disinfection from virus and bacteria.

Automated summary

A cost-effective sterilization box prototype was developed in this study, utilizing UV radiation and heat for disinfection of small items. The research showed that incubation under UV at 70 degrees Celsius effectively damaged the protein structure, demonstrating efficacy in inactivating SARS-COV-2 and achieving strong antibacterial effects.