Control and gating of kinesin-microtubule motility on electrically heated thermo-chips

First lab-on-chip devices based on active transport by biomolecular motors have been demonstrated for basic detection and sorting applications. However, to fully employ the advantages of such hybrid nanotechnology, versatile spatial and temporal control mechanisms are required. Using a thermo-responsive polymer, we demonstrated a temperature controlled gate that either allows or disallows the passing of microtubules through a topographically defined channel. The gate is addressed by a narrow gold wire, which acts as a local heating element. It is shown that the electrical current flowing through a narrow gold channel can control the local temperature and as a result the conformation of the polymer. This is the first demonstration of a spatially addressable gate for microtubule motility which is a key element of nanodevices based on biomolecular motors.