Repurposing Existing Molecular Machines through Accurate Regulation of Cooperative Motions

To
understand how different external stimuli affect the cooperative
motions in a molecular machine consisting of multiple components,
we have investigated at the atomic level the effects of pH, solvent,
and ionic strength on the mechanism underlying the ring-through-ring
movement in a saturated [3]­rotaxane. Our results indicate that different
external stimuli regulate the stable states, the shuttling rate, and
the mechanism that governs the ring-through-ring motion by controlling
the cooperative movement of the components and triggering a gamut
of responses, thereby opening to a vast number of potential applications,
such as quaternary logical calculations. The present work cogently
demonstrates that with existing nanomachines possessing a simple topology,
but using different external stimulian approach coined multidimensional
regulationchallenging tasks requiring precise control of the
molecular motions at play can be achieved, and our methodology is
particularly germane for de novo design of intelligent
molecular machines.