Assembly is traditionally considered an externally-directed process, where a person or machine assembles components according to a list of directions. An alternative process is self-assembly, where components themselves encode information specifying their ultimate position, and mere random mixing leads to spontaneous assembly. The complexity of structures self-assembled at molecular-scales has increased dramatically over the last ten years, especially in the field of DNA nanotechnology. In contrast to molecular self-assembly, the complexity of larger self-assembled products - i.e., of the scale routinely manufactured using externally-directed assembly - has remained low. This award supports fundamental research to generate the essential knowledge for the application of molecular-scale self-assembly techniques to larger scales. Such fundamental knowledge will eventually enable the development of a new manufacturing paradigm where diverse products are made through unsupervised and parallel self-assembly. Work in this project includes collaborations of scientists, engineers, and artists, as well as support of undergraduate research and education.
Rigid products self-assembled from flexible DNA strands now routinely consist of hundreds of unique components. Structures have been designed in 2D or 3D, with overall dimensions up to 100 nm. In contrast, self-assembly at larger scales remains limited to a handful of components, in part due to the low information content of the components and poor mixing strategies. This award supports the development of a theory describing the minimum material requirements for DNA-like self-assembly at any length scale. It will be demonstrated with the construction of a cm-scale DNA-like polymer system as well as a compatible stochastic mixing environment. Data taken from this new system will in turn demonstrate random perturbation, sequence-specific pairing of polymers using three and four-arm junctions, and complex product assembly using "Single Stranded Tile" and other frameworks. Analytical comparison to chemical kinetics will further demonstrate scale-independent phenomena and provide a theoretical basis for predicting performance at intermediate length scales.
