An enzyme-propelled target recycling amplification in combination with broad-spectrum quencher aggregated perylene for multiple MicroRNA detection

Abstract

MicroRNA (miRNA) are regarded as remarkable biomarkers for quick and non-invasive disease diagnosis. In this study, an enzyme-propelled target recycling amplification in combination with DNA/microRNA double strands and perylene diimide (PDI) broad-spectrum quencher was constructed for the determination of multiple miRNAs. The PDI aggregates can be highly efficient in quenching the RNA/DNA and DNA-labeled fluorophores from visible to near-infrared wavelength with quenching efficiencies of over 98 %. The broad-spectrum quenchers can be then employed to establish a multicolor miRNA sensing system by using a label-free approach. In the presence of miRNA, with the help of enzyme, the target recycling was initiated, resulting in the enhancement of fluorescence. The proposed method was highly sensitive to miRNA-21, miRNA-141 and miRNA-155, and the limit of detection obtained was 2.66 fM, 1.33 fM and 1 fM, respectively. Simultaneous and multiplexed detection of various miRNAs in a homogeneous solution was also accomplished. The sensor was used for the determination of miRNA content in human serum samples and the results obtained were satisfactory.