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

Abstract

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.