Inactivation of bacteriophages via photosensitization of fullerol nanoparticles.

The production of two reactive oxygen species through UV photosensitization of polyhydroxylated fullerene (fullerol) is shown to enhance viral inactivation rates. The production of both singlet oxygen and superoxide by fullerol in the presence of UV light is confirmed via two unique methods: electron paramagnetic resonance and reduction of nitro blue tetrazolium. These findings build on previous results both in the area of fullerene photosensitization and in the area of fullerene impact on microfauna. Results showed thatthe first-order MS2 bacteriophage inactivation rate nearly doubled due to the presence of singlet oxygen and increased by 125% due to singlet oxygen and superoxide as compared to UVA illumination alone. When fullerol and NADH are present in solution, dark inactivation of viruses occurs at nearly the same rate as that produced by UVA illumination without nanoparticles. These results suggest a potential for fullerenes to impact virus populations in both natural and engineered systems ranging from surface waters to disinfection technologies for water and wastewater treatment.