A DNAzyme-powered cross-catalytic circuit for amplified intracellular imaging.

A facile cross-catalytic circuit is engineered for intracellular microRNA (miRNA) imaging by facilely integrating a catalytic hairpin assembly (CHA) amplifier and DNAzyme biocatalyst through an ingenious feedback loop. These two indispensable catalytic reactions play vital roles in executing high-performance signal amplification, as demonstrated experimentally and theoretically.