Rapid and multiplex microRNA detection on graphically encoded silica suspension array

MicroRNA (miRNA), an 18-24-nucleotide noncoding RNA molecule, has become an ideal class of biomarker candidates for clinical diagnosis of cancers. By now, a number of detection methods for miRNAs have been developed on planar arrays and suspension arrays. In this work, we describe a hybridization-triggered fluorescence strategy for label-free and multiplex miRNA detection on graphically encoded silica suspension array. The total RNA is directly applied for analysis with an 8-mer Universal Tag which can be selectively captured by the capture probe via base-stacking effects. Benefiting from base-stacking effects, this novel method exhibits superb discrimination ability toward the 5′ and 3′ end single-nucleotide alteration. Mature miRNAs can be distinguished from their corresponding pre-miRNAs easily. Moreover, the estimated detection limit of 5 amol is comparable to some of the most sensitive methods. All these mentioned characteristics offer exciting possibilities for discovery and clinical applications.