Multiplexed fluorometric determination for three microRNAs in acute myocardial infarction by using duplex-specific nuclease and MoS 2 nanosheets

Circulating microRNAs are of diagnostic value for acute myocardial infarction (AMI). This study describes a fluorometric assay for multiplexed detection of the AMI biomarkers microRNA-499, microRNA-133a and microRNA-1. The assay involves the following two steps: (a) duplex-specific nuclease (DSN)-mediated signal amplification using aptamer-based sensor; (b) MoS 2 nanosheets-based multiplexed fluorometric signal detection, and fluorometric signals have excitation/emission maxima at 492/518 nm for microRNA-499, 565/580 nm for microRNA-133a and 649/663 nm for microRNA-1. The assay has detection limits of around 100 fM for all three microRNAs. The assay is highly specific and rapid. It demonstrates that the expressions of microRNA-499, microRNA-133a and microRNA-1 are significantly higher in AMI patients. The ROC curves allow a clear distinction to be made between AMI group and non-AMI group. Graphical abstract Schematic representation of a multiplexed fluorometric method based on duplex-specific nuclease (DSN)-mediated signal amplification and MoS 2 nanosheets-based fluorometric signal detection (DSN-MoS 2 ) for rapid, sensitive and specific detection of microRNAs in AMI.