Using DNA to program pathways in colloidal self-assembly

DNA is not just the stuff of our genetic code; it is also a means to build materials.
In this talk, Professor W. Benjamin Rogers, Assistant Professor of Physics at Brandeis, will present experiments showing that the information stored in DNA sequences can be used to design the entire self-assembly pathway, and not just its endpoint. Using grafted DNA strands to induce specific attractions between particles, and free DNA strands that compete to bind with the grafted ones, Rogers will show that it is possible to create colloids with exotic phase behavior, such as arbitrarily wide gas-solid coexistence, re-entrant melting, and even reversible transitions between different solid phases.

Grafting DNA onto colloidal nano- and microparticles can, in principle, ‘program’ them with information that tells them exactly how to self-assemble. Recent advances in our understanding of how this information is compiled into specific interparticle attractions have enabled the assembly of crystal phases not found in ordinary colloids, and could be extended to the assembly of prescribed, nonperiodic structures. However, structure is just one piece of a more complicated story; in actuality, self-assembly describes a phase transition between a disordered state and an ordered state, or a pathway on a phase diagram.

Professor W. Benjamin Rogers

Assistant Professor of Physics

Professor Rogers joined the Martin A. Fisher School of Physics at Brandeis University as an Assistant Professor in January 2016. His research program is focused on developing quantitative tools for understanding and controlling self-assembly at the nano- and micrometer scale. Before coming to Brandeis, Rogers was a postdoctoral fellow in the Manoharan Lab within the School of Engineering and Applied Sciences at Harvard University, where he studied assembly and optical properties of colloidal suspensions. He received his Ph.D. in Chemical and Biomolecular Engineering from the University of Pennsylvania in 2012. With John Crocker, Rogers used optical tweezers to study colloidal interactions and single-molecule kinetics. He graduated magna cum laude in 2005 from the University of Delaware, earning an Honors Bachelor of Chemical Engineering, with Distinction.