Photosensitized Production of Singlet Oxygen via C₆₀ Fullerene Covalently Attached to Functionalized Silica-coated Stainless-Steel Mesh: Remote Bacterial and Viral Inactivation

This study demonstrates the capability of a C₆₀-based sensitizer to remotely inactivate bacteria and viruses in air. The nucleophilic addition of amine groups attached to SiO₂ particles (used as free-standing support or as hosts electrosprayed on a stainless-steel mesh) to the double bonds of C₆₀ led to the production of recyclable sensitizers. The high-yield production of singlet oxygen (¹O₂) from the immobilized C₆₀ was established by studying the effects of ¹O₂ quenchers and enhancer on furfuryl alcohol (FFA) oxidation efficiency and wavelength-dependent FFA decay kinetics. We monitored the inactivation rates of Staphylococcus aureus and MS-2 bacteriophage in petri dishes at predetermined distances from the ¹O₂ source and identified the probability of remote microbial inactivation via ¹O₂, which occurred up to 10-15 cm from the source. This result accorded with epoxy moiety occurrence as an indication of singlet oxygenation in the Fourier Transform-Infrared spectra of cis-polybutadiene in remote positions.