Non-reversible changes in the UV-Vis spectra (solvatochromism) of C-60 fullerene in the binary solvent N-methyl-2-pyrrolidone/toluene are observed when varying the mixture composition. The solvatochromism strongly depends on the order of the mixture preparation. We attribute the effect to a great difference in the polarity of the liquid components, which determines different solvent-solute interaction with respect to the formation of charge-transfer complexes and, thus, provides conditions for selective solvation. The effect is also dependent on the temporal changes in the complexes C-60-N-methyl-2-pyrrolidone and C-60 cluster formation. (C) 2012 Elsevier B. V. All rights reserved.