Progress in Silicon Nanowire-Based Field-Effect Transistor Biosensors for Label-Free Detection of DNA

Silicon nanowire (SiNW), as one-dimensional semiconducting nanomaterial, has been incorporated into the filed-effect transistor (FET) devices to increase the efficacy and signal-to-noise in DNA sensing applications. Due to the advantages of high sensitivity, excellent selectivity, label-free detection, direct electrical readout, and miniaturization, SiNW FET-based DNA sensors have been regarded as an important tool in applications of molecular diagnostics, DNA sequencing, gene expressions, and drug discovery. Here, we review the recent progress in SiNW-FET sensors for label-free electrical DNA detection. We first introduce the working principle of SiNW-FET DNA sensors, SiNW fabrication technologies, bio-functionalization on nanowire surface, and enhancement of device sensitivity. Then we sum up the applications of SiNW sensors in detection of DNA hybridization, infectious viruses, microRNA, genetic change (DNA mutation, DNA methylation, and DNA repair), and protein-DNA interactions. We address several crucial points of sensing performance including sensitivity, selectivity, and limit of detection. Finally, the perspectives, challenges, and some solutions of the field are also discussed.