Fullerenes, especially the buckyball C₆₀, prove to be multifaceted in terms of biomedical applications. C₆₀, as a non-polar molecule, is nevertheless insoluble in water, let alone possessing any bioavailability.
Among various strategies to improve the solubility of C₆₀, Eudes E. Fileti of Universidade Federal de São Paulo, SP, Brazil, and Vitaly V. Chaban of Center for Biomembrane Physics, Odense, Denmark, investigate the efficacy of an imidazolium ionic liquid ([C₄C₁IM][BF₄^–]) using quantum mechanical calculation.

The seaearchers reveal that the hydrophilic cations in [C₄C₁IM][BF₄^–] can form complexes with C60 through π–π interactions, thus effectively separating and dispersing C₆₀ molecules. This approach evades the trouble of tedious covalent chemical modification, and the fact that about 10 to 20 mol% of [C₄C₁IM][BF₄^–] is able to completely cover the surface of C₆₀ also minimizes toxicity-associated risks.

• Imidazolium Ionic Liquid Helps to Disperse Fullerenes in Water,
  Eudes Eterno Fileti, Vitaly V. Chaban,
  J. Phys. Chem. Lett. 2014, 5, 1795−1800.
  DOI: 10.1021/jz500609x