ChEMS Seminar: Dynamic, Reconfigurable Materials and Nanostructures Built with DNA

Abstract: Materials within living systems have a complex structure that constantly reorganizes in order to continue to function reliably as the environment changes. Commonly, this structure arises because a simple set of components are assembled and reorganized by control over assembly kinetics, sensors and signal transduction cascades that translates information about the state of the environment to direct assembly and reorganization processes. These rules allow a material to take on a different configurations and through feedback between the environment and the assembly process, adapt to its surroundings and improve its function. For example, tubulin can be organized into cilia, fibrous networks or machines such as the spindle, and the extracellular matrix, an extended matrix composed of a relatively small number of principle protein components, is continually growing and being digested and remodeled in response to interaction with cells within a tissue. Could we build materials that can, like biological materials, respond and adapt in a myriad of ways to multiple features of the environment? Such responsiveness could lead to the design of soft robots, self-healing materials or biomaterials that can continue to improve their function over time.

To build such materials we need both structural components that can receive signals from the environment in chemical form and respond to these signals in ways that can be combined to engineer complex global behaviors. I’ll describe work in my laboratory toward building a range of DNA nanostructures and hydrogels that can interpret the shape of the physical environment through kinetic engineering of assembly processes, and that can dynamically respond to a range of environmental signals using different sets of local rules for assembly, disassembly and reorganization. I’ll also show how we can build “online” molecular circuits that can respond to inputs, time multistage responses and enable feedback between the state of the circuits and the state of the material. Finally, the ability to readily functionalize DNA-based materials and integrate them with other chemical components allows us to translate these ideas into the design of functional systems.

Bio: Rebecca Schulman is an assistant professor of chemical and biomolecular engineering and computer science at Johns Hopkins University. She received degrees in math and computer science from MIT, and a doctorate from Caltech in computation and neural systems. Schulman joined the faculty at Johns Hopkins after serving as Miller research fellow in physics at U.C. Berkeley. Recent awards include a DARPA Young Faculty Award (2016), a DOE Early Career Award (2016), an NSF Career Award (2013) and a Turing Scholar Award (2012).

Hosts: Alon Gorodetsky and Allon Hochbaum