Silicon-Nanowire-Based CMOS-Compatible Field-Effect Transistor Nanosensors for Ultrasensitive Electrical Detection of Nucleic Acids

Abstract

We herein report the design of a novel semiconducting silicon nanowire field-effect transistor (SiNW-FET) biosensor array for ultrasensitive label-free and real-time detection of nucleic acids. Highly responsive SiNWs with narrow sizes and high surface-to-volume-ratios were "top-down" fabricated with a complementary metal oxide semiconductor compatible anisotropic self-stop etching technique. When SiNWs were covalently modified with DNA probes, the nanosensor showed highly sensitive concentration-dependent conductance change in response to specific target DNA sequences. This SiNW-FET nanosensor revealed ultrahigh sensitivity for rapid and reliable detection of 1 fM of target DNA and high specificity single-nucleotide polymorphism discrimination. As a proof-of-concept for multiplex detection with this small-size and mass producible sensor array, we demonstrated simultaneous selective detection of two pathogenic strain virus DNA sequences (H1N1 and H5N1) of avian influenza.

Silicon Nanowire Field-effect-transistor-based Biosensor for Biomedical Applications

“…(11) The back-gate-controlled field effect on device sensitivity was studied using a pH sensing experiment by our group. (10) Figure 3(a) shows as-prepared SiNW devices characterized as nanoscale pH sensors. The real-time current of the silicon nanowire decreased stepwise with a discrete change in pH from 5.0 to 9.0 [ Fig.…”

“…In general, there are two major techniques for fabricating SiNWs: top-down (10) and bottomup. (11) SiNWs prepared by the bottom-up approach are normally catalytically synthesized by chemical vapor deposition (CVD).…”

Silicon nanowire-transistor biosensor for study of molecule-molecule interactions

“…For instance, Gao et al (2011) reported a highly responsive FET sensor array for the ultrasensitive and real-time detection of DNA. A CMOS-compatible top-down anisotropic self-stop etching technology was used to fabricate a narrow-size nanowire with high surface-to-volume ratios ( Figure 8A).…”

“…In addition, SiNW-FETs can perform rapid, ultrasensitive, and multiplexed detection of the desired targets independent of any labels (Patolsky et al 2006a, Gao et al 2007). In the past decade, this nanobiosensor has been widely used to detect a variety of molecule binding events with sensitivities below picomolar concentrations (Gao et al 2011(Gao et al , 2012(Gao et al , 2013. Because of the broad implementation of SiNW biosensor in molecule-molecule interactions and an extendable application in real-time in vivo monitoring (Tian et al 2010, Duan et al 2012a, Qing et al 2014, we summarize the recent advances in SiNWFETs with emphasis on a variety of molecule interactions.…”

Tuning the surface conditioning of trapezoidally shaped silicon nanowires by (3-aminopropyl)triethoxysilane

“…[1][2][3] Having dimensions on the same scale like the target molecules and a high surface-to-volume ratio, their electrical response is expected to exceed that of more conventional thin-film devices for real-time monitoring of complex environments. [4][5][6][7][8] A plethora of studies addressed their performance as ultra-sensitive detectors for gas, [9][10][11] pH, 1,12,13 nucleic acids, 14 and proteins. 1,12,15 For biosensing, SiNWs were developed for use mainly in aqueous media, in situ 16 -akin to implantable devices, or ex situ 1,12,13 via microfluidic approaches.…”