Ultrasensitive detection of microRNA-10b through target-triggered catalytic hairpin assembly and upconversion nanoparticles-based luminescence resonance energy transfer

The overexpression of microRNA-10b (miRNA-10b) is closely associated with hepatocellular carcinoma (HCC), which may act as an advance biomarker to diagnose HCC early. Here, a novel luminescent nanosensor for the ultrasensitive detection of miRNA-10b was firstly developed by target-triggered catalytic hairpin assembly ( CHA ) and upconversion nanoparticles (UCNPs)-based luminescence resonance energy transfer (LRET). The hybridization process of DNA1-modified UCNPs with DNA2-modified gold nanoparticles (AuNPs) makes the energy donor (UCNPs) and acceptor (AuNPs) into close proximity, resulting in luminescence quenching of UCNPs. The miRNA-10b can hybridize with the hairpin structure of DNA2, releasing the recognition domain site and activate the CHA reaction with its signal amplification chain (H3). At the same time, the LRET was inhibited accompany with the AuNPs moved away from the UCNPs, which resulted in the luminescence recovery of UCNPs. The miRNA-10b can be quantified by measurement of the luminescence recovery rate of UCNPs. The sensor has high sensitivity with a detection limit of 8.96 fM. In addition, the sensor can be used to the discrimination of miRNA-10b expression levels in human hepatocarcinoma and hepatocyte cell lines with satisfactory results. The technique shows great promise for early diagnosis of HCC because of its high sensitivity and selectivity .