Parametrization and application of a coarse grained force field for benzene/fullerene interactions with lipids.

Recently, we reported new coarse grain (CG) force fields for lipids and phenyl/fullerene based molecules. Here, we developed the cross parameters necessary to unite those force fields and then applied the model to investigate the nature of benzene and C(60) interactions with lipid bilayers. The interaction parameters between the phenyl and lipid CG sites are based on experimental and all atom (AA) molecular dynamics (MD) data. The resulting force field was tested on benzene rich lipid bilayers and shown to reproduce general behavior expected from experiments. The parameters were then applied to C(60) interactions with lipid bilayers. Overall, the results showed excellent agreement with AA MD and experimental observations. In the C(60) lipid systems, the fullerenes were shown to aggregate even at the lowest concentrations investigated.