Metastable Dumbbell Probe-Based Hybridization Chain Reaction for Sensitive and Accurate Imaging of Intracellular-Specific MicroRNAs In Situ in Living Cells

Sensitive and accurate imaging of intracellular-specific microRNAs (miRNAs) in situ in living cells is seriously challenged by the susceptibility of nucleic acid probes and the low dynamics of the hybridization reaction in cellular environments. Herein, we engineer a set of new metastable dumbbell probes (M xDPs) to overcome these key limitations by concurrently boosting transfection, antidigestibility, assembly dynamics, and nanostructural uniformity. The M xDPs can maintain their stability up to 16 h in living cells and produce uniform and dense DNA nanostructures rapidly (