Lipid Membranes as Solvents for Carbon Nanoparticles

Fullerene is scarcely soluble in most solvents, including alkanes. Yet, it has been shown that C-60 dissolves in lipid bilayers, whose interior is chemically identical to alkanes. Here, we use molecular simulations to explain why lipid bilayers are better than alkanes at dissolving fullerene clusters. Fullerene aggregation is driven by entropy, but enthalpic contributions determine the difference between alkanes and bilayers. Surprisingly, confinement and chain alignment in the bilayer do not affect fullerene aggregation, while solvent density and the perturbation of solvent-solvent interactions are key factors.