Multi scale computer simulations of the self-assembly of block copolymeric beta-peptides

There is considerable interest in a class of molecules made from $\beta$-amino acids (which contain an additional backbone carbon atom when compared with natural amino acids). Block copolymers of $\beta$-peptides, where one block is hydrophobic and the other is hydrophilic, self-assemble into micelles. In this work we use computer simulations to provide insight into the self-assembly of these molecules. All-atom simulation results for the free energy of association of a pair of these block co polymeric $\beta$- peptides show that a {\it homochiral} hydrophobic block promotes self assembly compared to a {\it heterochiral} hydrophobic block, consistent with experiment. We have also developed a coarse-grained model for these block co-polymers and simulations using this model show that these molecules spontaneously forms micelles, and the morphology of these micelles is concentration dependent, with spherical micelles at low concentrations and worm-like micelles at high concentrations.