Study of Fullerene Aqueous Dispersion Prepared by Novel Dialysis Method: Simple Way to Fullerene Aqueous Solution

A simple approach for large-scale production of aqueous dispersions of fullerene C60 (nC60) with good stability was developed by mixing a solution of crystalline fullerene in N-methylpyrrolidone (NMP) with water followed by exhaustive dialysis against water. Addition of amino acids or sugars at low concentration before dialysis increases the stability of the dispersion. Measurement of the size and ξ-potential of particles in nC60 showed that their average diameter is 100 nm and charge about –30 mV. IR spectra of the dried dispersions showed the presence of a broadband characteristic for C‒O bond. Changing the solvent NMP to pyridine does not significantly affect the spectral characteristics of the resulting dispersion. Our data suggest that the fullerene molecule in nC60 is associated with MP and water molecules, and obviously is partially hydroxylated. The proposed method is promising for the preparation of aqueous solutions of endofullerenes.