Y-shaped nanoprobe-based DNA microarray for rapid detection of multiplex miRNAs with single-nucleotide specificity

Multiplexed detection of microRNAs (miRNAs) is highly valuable for cancer diagnosis, prognosis and monitoring. However, the existing miRNA testing methods do not align with the requirements such as high-specificity, high-speed multiple miRNA detection owing to the short length and high homologous sequence similarity of miRNAs. Herein, we developed a Y-shaped nanoprobe-based DNA microarray that is capable of rapid, multiplexed detection of miRNA exhibiting single-nucleotide specificity in 1 min. The washing steps involved in traditional microarray detection are eliminated, simplifying the procedure. In addition, we directly applied this method to the detection of miRNAs in tumor cell extracts. Moreover, the incorporation of exponential amplification reaction (EXPAR) can effectively improve the sensitivity of the microarray platform. The EXPAR-based method exhibits a detection limit of 80 aM, with the amplification step requiring only 20 min. Such a fast, multiplexed detection method for miRNAs can offer access to point-of-care diagnostics.