Electrical docking of microtubules for kinesin-driven motility in nanostructures.

We demonstrate localized electrical control of the docking of microtubules onto engineered kinesin-coated structures. After applying a voltage to a gold electrode, we observe an enhanced transport of microtubules from solution toward the surface and a subsequent increase of the amount of moving microtubule shuttles. Switching off the voltage leads to a partial detachment of microtubules from the surface. The surface coverage of microtubules, during both the docking and undocking events, follows an exponential time dependence. We provide a simple kinetic model, incorporating the equilibrium between free and surface-bound microtubules, that explains these data.