Fullerenol C(OH): Antioxidant, Cytoprotective, Anti-Influenza Virus Activity, and Self-Assembly in Aqueous Solutions and Cell Culture Media.

Viral infections and many other dangerous diseases are accompanied by the development of oxidative stress, which is a consequence of an increase in the level of the reactive oxygen species (ROS). In this regard, the search for effective antioxidants remains highly relevant. We tested fullerenol C(OH) in the context of the connection between its self-assembly in aqueous solutions and cell culture media, antiradical activity, UV cytoprotective action, and antiviral activity against international reference strains of influenza virus A(H1N1)pdm09, A(H3N2), and B subtypes in vitro on the MDCK cell line. Various characterization techniques, including Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, NMR and ESR spectrometry, MALDI-TOF mass spectrometry, thermal analysis (TGA and DSC), dynamic light-scattering (DLS), and ζ-potential measurements, were used to confirm the production of fullerenol and study its self-assembly in aqueous solutions and cell culture media. Fullerenol C(OH) demonstrated the ability to scavenge DPPH, OH, O radicals and O and was non-toxic in the range of the studied concentrations (up to 200 μg/mL) when incubated with MDCK cells for 24 h. In addition, fullerenol exhibited a cytoprotective effect under UV irradiation (EC = 29.7 ± 1.0 μM) and showed moderate activity against human influenza viruses of subtypes A(H1N1)pdm09 (SI = 9.9 ± 4.6) and A(H3N2) (SI = 12.5 ± 1.3) when determined by the hemagglutination assay (HA-test) and the MTT assay. At the same time, C(OH) was ineffective in vitro against the actual strain of influenza B virus (Victoria lineage). The high bioavailability of fullerenol in combination with its cytoprotective effect, as well as its antiradical and antiviral activity combined with a relatively low toxicity, allows to consider it a promising compound for biomedical applications.