CHIRALMICROBOTS · Chiral Nanostructured Surfaces and Colloidal Microbots

From scientific publications to the popular media, there have been numerous speculations about wirelessly controlled microrobots (microbots) navigating the human body. Microbots have the potential to revolutionize analytics, targeted drug delivery, and microsurgery, but until now there has not been any untethered microscopic system that could be properly moved let alone controlled in fluidic environments. Using glancing angle (physical vapor deposition) we will grow billions of micron-sized colloidal screw-propellers on a wafer. These chiral mesoscopic screws can be magnetized and moved through solution under computer control. The screw-propellers resemble artificial flagella and are the only ‘microbots’ to date that can be fully controlled in solution at micron length scales. The proposed work will advance the fabrication so that active microbots can be applied in rheological measurements and analytics. We will use these novel probes in bio-microrheology with the potential to probe the viscoelastic properties of membranes and tissues, and to explore questions of micro-hydrodynamics. At the same time we will develop these structures as ""colloidal molecules"" and grow asymmetric mesoscopic particles with tailored shapes and properties. We propose experiments that allow the observation of fundamental effects, such as chiral Brownian motion, something that exist at the molecular scale, but has never been observed to date. Similarly, we will be able to demonstrate for the first time chiral separations based purely on physical fields. The proposed technical advances of the growth of nanostructured surfaces will at the same time permit wafer-scale 3-D nano-structuring for photonic and plasmonic applications, which we plan to demonstrate. We will develop a system for targeted drug delivery, study the interaction of swarms of microbots and devise techniques to control and image these swarms.""