Sensitive detection of intracellular microRNA based on a flowerlike vector with catalytic hairpin assembly

A flowerlike nanovector is developed for the fluorescence imaging and detection of miRNA in live cells with catalytic hairpin assembly. This horned vector provides a high loading efficiency of DNA amplifiers for multiple signal outputs and is applied to detect miRNA-21 in an average single HeLa cell, showing promising application in trace detection of intracellular biomolecules.