Surface Imaging by Self-Propelled Nanoscale Probes

A new approach to image microscopic surface properties is introduced. Information about surface properties such as topography is obtained by repeated acquisition of an optical signal from a large number of microscopic, self-propelled probes moving on random paths across a surface. These self-propelled probes sample the surface in a statistical process in contrast to the deterministic, linear sampling performed by a scanning probe microscope. This method is experimentally demonstrated using microtubules as probes, which are moved by the motor protein kinesin.