Simultaneous detection of acute myocardial infarction -related miR-199a and miR-499 based on a dual-emission CdTe fluorescent probe and T7 exonuclease-assisted signal amplification

The early diagnosis of acute myocardial infarction (AMI) was a tough nut in both clinical medicine and forensic science since the occurrence of gross changes needed at least 12 h. Compared to other diagnostic methods, microRNA was reported as an earlier cardiac biomarker with higher sensitive. In this work, we designed a novel fluorescent analytical strategy using a dual-emission probe based on T7 Exo-assisted target recycling amplification for simultaneous detection of AMI-related miR-199a and miR-499, which could indicate myocardial ischemia or damage in AMI. The dual-emission probe was conducted by yellow-emission and red-emission CdTe quantum dots capped with beta-cyclodextrin. The florescence of probe was firstly quenched by graphene oxide (GO) and then recovered in the presence of target miR-199a and miR-499. Under the optimized conditions, the limit of detection as low as 0.1 pM was obtained and the overall test could be performed within 50 min. Besides, the simultaneous detections of microRNAs in spiked serum samples were achieved with the recovery of 81.3–109.6%, which suggested the potential method for diagnosis in practical. The advantages of this method include easy operation, high accuracy and low labor cost, which makes point-of-care test possible both in hospital and forensic application.