Programmable Modulation of Copper Nanoclusters Electrochemiluminescence via DNA Nanocranes for Ultrasensitive Detection of microRNA

The DNA nanocrane with functionalized manipulator and fixed-size base offered a programmable approach to modulate the luminous efficiency of copper nanoclusters (Cu NCs) for achieving remarkable electrochemiluminescence (ECL) enhancement, further the Cu NCs as signal label was constructed in biosensor for ultrasensitive detection of microRNA-155. Herein, the DNA nanocrane was first constructed by combining binding-induced DNA assembly as manipulator and tetrahedral DNA nanostructure (TDN) as base, which harnessed a small quantity of specific target (microRNA (miRNA)-155) binding to trigger assembly of separate DNA components for producing numerous AT-rich double-stranded DNA (dsDNA) on the vertex of TDN. Upon the incubation of Cu2+ on the AT-rich dsDNA, each DNA-stabilized Cu NCs probe could be in situ electrochemically generated on an individual TDN owing to the A-Cu2+-T bond. Thus, the generation of Cu NCs was highly regulated with AT-rich dsDNA as the template, and its lateral distance was tuned by the...