Dr. Aksimentiev has a background in soft matter physics and now deploys computational methods to investigate physical phenomena at the interface of solid-state nanodevices and biological macromolecules. In his graduate work, he applied methods of field theory to predict phase diagrams of polymer mixtures, focusing on the conformational properties of single macromolecules. Subsequently, he discovered a universal scaling of the morphological measures quantitatively characterizing the topology of the three-dimensional patterns that emerge during the process of phase transition. In the focus of his current research program are systems comprising silicon-based synthetic membranes and biomolecules— DNA, proteins, and lipids—assembled into novel silicon circuits that can act as sensors, tweezers, and scaffolds for assembly of biosynthetic complexes.
Human civilization runs on rotary motors, from cars to planes, from conveyor belts to power generators, from pumps to ice cream mixers. Surprisingly, very few examples of rotary motors exist at the nanoscale. FoF1 ATP synthase transforms the energy of electrochemical gradients to power a cycle of catalytic reactions to synthesize the universal energy carrier, ATP. The flagellum motor uses the electrochemical gradient to spin a polymer filament that propels a bacterium in water. However, the physical mechanism utilized by these biological motors—diffusion biased by chemical reactions— is fundamentally different from the mechanisms utilized in macroscopic man-made machines. Is it really not possible to construct a nanoscale system that directly converts flux into thrust and, perhaps, do that using an electric field as an energy source? This lecture will highlight our recent efforts to develop such nanoscale electro-motors using DNA as a building material. First, I will show that a single DNA duplex can itself act as a tiny electromotor, spinning billions of revolutions per minute when subject to external electric fields. I will next describe our efforts to build more complex DNA electromotors and to realize them in practice. The lecture will highlight the applications of the all-atom molecular dynamics method to design molecular motors and to unravel microscopic phenomena that give rise to puzzling experimental observations.
Precise, reproducible manufacturing of man-made materials at the nanoscale.