Ultrasensitive fluorescent biosensor for miRNA-34a detection: Magnetic separation coupled with cascade amplification of duplex-specific nuclease-assisted and hybridization chain reaction.
TL;DR
A highly sensitive fluorescent biosensor for miRNA-34a detection by integrating magnetic separation with cascade amplification of duplex-specific nuclease (DSN) and hybridization chain reaction (HCR) and showing excellent specificity for discriminating against interfering miRNAs is developed.
Abstract
Lung cancer is the most common and lethal malignancy worldwide, with non-small cell lung cancer (NSCLC) accounting for approximately 85% of cases and exhibiting high mortality rates. MicroRNA-34a (miRNA-34a) is a promising biomarker, therapeutic target, and prognostic indicator for NSCLC, necessitating sensitive and specific detection methods for early diagnosis and improved clinical management. Here, we developed a highly sensitive fluorescent biosensor for miRNA-34a detection by integrating magnetic separation with cascade amplification of duplex-specific nuclease (DSN) and hybridization chain reaction (HCR). Under optimal conditions, the biosensor exhibits a wide linear range (1.0 fM-10.0 nM) and an ultralow detection limit (0.3 fM), with excellent specificity for discriminating against interfering miRNAs. Moreover, the sensor was successfully validated in clinical blood samples, showing excellent agreement with RT-qPCR results. Collectively, this method provides a sensitive and specific tool for trace miRNA-34a detection, demonstrating significant potential for early NSCLC diagnosis and improved patient management.