Brandeis University

 

Self-assembly of simple subunits into multi-subunit structures with increased complexity and functionality underlies many biological processes and is becoming an important route to bottom-up materials design. In this talk I will consider a special class of self-assembly processes --- self-limiting assembly --- defined as an assembly process that autonomously terminates at an equilibrium structure with a well-defined, finite size that is much larger than the size of individual subunits. I will begin with a brief overview of the basic statistical mechanical framework that describes the thermodynamics of self-assembly. With this framework, I will introduce the physical ingredients that are required to achieve self-limited assembly. I will then discuss three (time permitting) examples of self-limiting assembly, with results from theoretical and computational modeling as well as from experiments by collaborators: (1) Virus assembly and budding; (2) Synthetic capsids (icosahedral shells) formed by self-assembling DNA origami subunits; and (3) Tubules whose self-assembly terminates at a well-defined length due to geometric frustration.