Designing DNAzyme‐Powered Nanomachines Simultaneously Responsive to Multiple MicroRNAs

Herein, a DNAzyme-powered nanomachine responsive to multiple hepatocellular carcinoma (HCC)-related miRNAs derived from clinical samples was designed. Initially, three types of nanomachines were constructed with dye molecule [(fluorescein (FAM), tetramethylrhodamin (TMR), and Cyanine 5 (Cy5)]-labeled DNA-RNA chimeric substrates and a specific recognized probe for the corresponding miRNAs target. Once the target miRNAs were captured by two recognizing probes, the DNA nanomachine was initiated, leading to the hybridization between the DNAzyme and the substrates. With the help of a cofactor, the automatic operation of the nanomachine was driven by cyclic cleavage of the DNAzyme. Meanwhile, we also explored the recognition behavior between the recognizing probe and the target miRNA. Subsequently, these DNAzyme-powered nanomachines were developed for the homogeneous and simultaneous detection of three target miRNAs at the femtomloar level. Furthermore, the potential in clinical diagnosis was proven by the successful determination of target miRNA in real clinical samples. Thus, this nanomachine-based strategy possesses significant potential to be an innovation in miRNA analysis methodology.