RNA responsive and catalytic self-assembly of DNA nanostructures for highly sensitive fluorescence detection of microRNA from cancer cells.

Catalytic self-assembly of DNA nanostructures triggered by microRNA 21 (miR-21) is achieved through isothermal toe-hold strand displacement reactions. The miR-21 is autonomously recycled during the self-assembly process, which makes the generation of the DNA nanostructures proceed in a catalytic fashion. The miR-21-triggered self-assembly of DNA nanostructures can also serve as a remarkable signal amplification platform to achieve ultrasensitive detection of miR-21 from as low as 10 MCF-7 human breast cancer cells.