Label-Free Direct Detection of MiRNAs with Poly-Silicon Nanowire Biosensors.

The diagnostic and prognostic value of microRNAs (miRNAs) in diseases becomes promising. Owing to fast response and high sensitivity, silicon nanowire (SiNW) biosensor has been considered a potential tool for miRNAs detection. Here, we describe a booming method to detect miRNAs with poly-silicon nanowire biosensors. Standard and real miRNA samples are applied in this study. The results show a limitation of 1 fM in the detection of standard miRNA sample with our poly-nanowire devices. Meanwhile, one-base mismatched sequence could be distinguished. Furthermore, these poly-SiNW arrays can detect snRNA U6 in total RNA samples extracted from HepG2 cells with a detection limitation of 0.2 μg/mL.