Targeted Activation of Molecular Transportation by Visible Light.

Regulated transportation of nanoscale objects with a high degree of spatiotemporal precision is a prerequisite for the development of targeted molecular delivery. In vitro integration of the kinesin-microtubule motor system with synthetic molecules offers opportunities to develop controllable molecular shuttles for lab-on-a-chip applications. We attempted a combination of the kinesin-microtubule motor system with push-pull type azobenzene tethered inhibitory peptides (azo-peptides) through which reversible, spatiotemporal control over the kinesin motor activity was achieved locally by a single, visible wavelength. The fast thermal relaxation of the cis-isomers of azo-peptides offered us quick and complete resetting of the trans-state in the dark, circumventing the requirement of two distinct wavelengths for two-way switching of kinesin-driven microtubule motility. Herein, we report the manipulation of selected, single microtubule movement while keeping other microtubules at complete rest. The photoresponsive inhibitors discussed herein would help in realizing complex bionanodevices.