Synthesis and Characterization of a Water-Soluble Nanomaterial via Deep Nitration of Light Fullerene C60

A direct non-catalytic synthesis of a new water-soluble polynitro-hydroxylated fullerene derivative, C60(NO2)18(OH)2, was carried out using a mixture of concentrated nitric and sulfuric acids. The resulting poly-nitro adduct was comprehensively characterized by elemental C-H-N analysis, energy-dispersive X-ray spectroscopy, infrared (IR) and electron spectroscopy, nuclear magnetic resonance (NMR), high-performance liquid chromatography (HPLC), and thermogravimetric analysis (TGA). A detailed investigation of the physicochemical properties of aqueous solutions of C60(NO2)18(OH)2 demonstrated that the synthesized compound is a previously undescribed mixed polynitro-hydroxyl adduct of light fullerene C60, featuring a high degree of nitration (18 nitro groups per fullerene core). The composition and structure of the adduct were confirmed by spectroscopic and refractometric analyses. In terms of redox behavior, the compound exhibits significant reducing and antioxidant properties. These physicochemical characteristics suggest the potential of C60(NO2)18(OH)2 for further development as a biocompatible nanomaterial suitable for medical applications.