Enzyme-Induced Kinetic Control of Peptide-Polymer Micelle Morphology

In this paper, experiment and simulation were combined to provide a view of the molecular rearrangements underlying the equilibrium and nonequilibrium transitions occurring in stimuli-responsive block copolymer amphiphile self-assemblies. Three block copolymer amphiphiles were prepared, each consisting of a hydrophilic peptide brush, responsive to proteolytic enzymes, and containing one of three possible hydrophobic blocks: (1) poly(ethyl acrylate), (2) poly(styrene), or (3) poly(lauryl acrylate). When assembled, they generate three spherical micelles each responsive to the addition of the bacterial protease, thermolysin. We found core-block-dependent phase transitions in response to the hydrophilic block being truncated by the stimulus. In one example, we found an unexpected, well-defined, pathway-dependent spherical micelle to vesicle phase transition induced by enzymatic stimulus.