Autonomous biomimetic motors fueled by peptide assembly
A new hybrid biomimetic motor system powered by the release of consisting of diphenylalanine (DPA) peptides from a metal-organic framework (MOF) in a manner resembling the metabolization and production of resources in cells. In nature, biological motors convert chemical free energy to mechanical power directly by creating isothermal and non-equilibrium conditions through biochemical reactions such as the metabolism of chemicals by cells to produce products that are simultaneously exploited as energy resources. In this new bioinspired system, a MOF is used to encapsulate DPA peptides in its pores. Release of the stored peptides and their subsequent reconfiguration into hydrophobic assemblies creates a non-equilibrium condition by generating a large surface tension gradient. The chemical energy generated by this process propels the MOF to swim like bacteria towards the higher surface tension side of the gradient. Lessons learned from understanding how this “motor” operates could be used to design systems that sense, capture, and store or “metabolize” target chemicals and control the local environment of materials.
Y. Ikezoe, G.Washino, T. Uemura, S. Kitagawa, and H. Matsui, Autonomous motors of a metal–organic framework powered by reorganization of self-assembled peptides at interfaces, Nature Materials, 2012, 11,1081-1085.