A MnO x -nucleic acid nanoprobe with enzyme-free cascade signal amplification for ultrasensitive intracellular microRNA imaging

-nucleic acid nanoprobe was constructed for catalytic imaging of microRNA in living cells based on the combination of catalytic hairpin assembly, hybridization chain reaction, and DNAzyme amplification. This nanoprobe exhibited ultrahigh sensitivity and specificity, and could distinguish tumor cells and normal cells by live cell microRNA imaging.