Control of nucleation in supramolecular polymerization

Natural molecular machines convert chemical energy into mechanical energy and participate in the key activities in cells like cargo transportation, membrane deformation and cell migration. Among all natural molecular machines, the cytoskeleton is the one that can generate directional force through self-assembly. Designing an artificial counterpart of the cytoskeleton is important in the development of artificial molecular machines. To mimic the way that the natural cytoskeletons transport cargos with a synthetic supramolecular polymerization motor, one of the key points are the control of the nucleation.
In this research, we focus on the control of nucleation in supramolecular polymerization from four aspects. By tuning the structure of the building block, we find a strategy to build up a high kinetic barrier for the trapped state of the building block to elongate the nucleation time; By adding the special molecules which cannot self-assemble themselves but have specialized interaction with the building block we manage to shorten the nucleation time of the building blocks. These special molecules can work as nucleation accelerators; By mixing the relatively polar solvent with the apolar solvent we find another simple strategy to build up a high kinetic barrier to elongate the nucleation time into the scale of minutes for the trapped building blocks with the stabilization of solvation; Finally, we investigate the influence of the interface between the solution and the solid on the supramolecular polymerization.