Rational design of dynamic DNA self-assembly through a responsive-bond-embedded loop.

Herein, we propose a versatile strategy for dynamic DNA self-assembly through a control loop embedded with responsive chemical groups. Responsive to a stimulus, the inserted chemical group will enable the formation or cleavage of the control loop, determining its intact or cleaved states. When the loop is intact, DNA self-assembly occurs; otherwise, the assembly process is prevented. The "Turn-On", "Turn-Off", and reversible "On-Off-On" systems have been achieved for two DNA assembly systems by incorporating different chemical groups, responding to various stimuli such as light irradiation, metal ions, and small molecules. The loop-controlled dynamic DNA self-assembly strategy holds excellent designability and versatility, enriching the existing regulation reservoir and bringing new opportunities for dynamic DNA nanotechnology.