Guided Self-Assembly of DNA Tiles into One- and Two-Dimensional Patterns Using Strand-Displacement and Optochemical Pathways

Self-assembly is a key process in living systems to facilitate the formation of intricate structures of biomolecules with properties vital to biological functions. In engineered systems, controlling self-assembly in response to external stimuli is crucial for leveraging biomolecular behaviors for technological applications. In this study, we present two approaches to direct the linear growth and 2D self-assembly of DNA tiles. The first strategy involves using toehold-mediated strand-displacement reactions. The second approach employs a photoresponsive duplex module, which contains a tile-activator strand coupled with a complementary strand that incorporates a photocleavable o-nitrobenzyl group. Exposure to UV light triggers the cleavage of this photocleavable linker, destabilizing the duplex module and releasing the activator strand, resulting in activation of the DNA-tile assembly. This guided self-assembly in DNA-based systems demonstrates new potential in developing biosensors, molecular machines, and targeted drug delivery.