High fluorescence quenching probe-based reverse fluorescence enhancement LFTS coupling with IS-primer amplification reaction for the rapid and sensitive Parkinson Disease-associated MicroRNA detection

Parkinson Disease (PD) is the second-most common neurodegenerative disorder in the population. Recent researches indicated that hsa-microRNA 5010-3p (miR-5010) and hsa-microRNA 331-5p (miR-331) were significantly important for the detection of PD. So, in this work, a kind of high fluorescence quenching probe-based reverse fluorescence enhancement lateral flow test strip (rLFTS) was constructed to realize the synchronous detection of miR-5010 and miR-331. The formation of black hole quencher 2 (BHQ2) coating gold nanoparticles (AuNPs) effectively enhanced the fluorescence quenching property of the probes so as to significantly improve the detection sensitivity. This rLFTS also coupled with "invading stacking primer" (IS-primer) isothermal amplification reaction (ISAR) to accomplish rapid, sensitive, specific, and synchronous detection of PD-associated microRNA (miRNA). The whole detection time was shorter (35 min), and the limit-of-detection (LOD) reached to fM level. For the high accuracy diagnosis of PD, the synchronous determination of miR-5010 and miR-331 was successfully realized on one rLFTS by labeling fluorescent molecules to different T-line. This rLFTS also allowed for miRNA detection in total microRNA extracts from whole blood samples of PD patients, which performed important value in PD diagnosis and biomedical research.