CMOS‐Compatible Silicon Nanowire Field‐Effect Transistors for Ultrasensitive and Label‐Free MicroRNAs Sensing

Abstract

MicroRNAs (miRNAs) have been regarded as promising biomarkers for the diagnosis and prognosis of early-stage cancer as their expression levels are associated with different types of human cancers. However, it is a challenge to produce low-cost miRNA sensors, as well as retain a high sensitivity, both of which are essential factors that must be considered in fabricating nanoscale biosensors and in future biomedical applications. To address such challenges, we develop a complementary metal oxide semiconductor (CMOS)-compatible SiNW-FET biosensor fabricated by an anisotropic wet etching technology with self-limitation which provides a much lower manufacturing cost and an ultrahigh sensitivity. This nanosensor shows a rapid (< 1 minute) detection of miR-21 and miR-205, with a low limit of detection (LOD) of 1 zeptomole (ca. 600 copies), as well as an excellent discrimination for single-nucleotide mismatched sequences of tumor-associated miRNAs. To investigate its applicability in real settings, we have detected miRNAs in total RNA extracted from lung cancer cells as well as human serum samples using the nanosensors, which demonstrates their potential use in identifying clinical samples for early diagnosis of cancer.

Preparation of Silicon Nanowire Field-effect Transistor for Chemical and Biosensing Applications

“…As shown in Table 1, several studies have used NWFET-based biosensors for label-free, ultra-high-sensitivity, and real-time detection of various biological targets, including a single virus 2 , adenosine triphosphate and kinase binding 3 , neuronal signals 4 , metal ions 5,6 , bacterial toxins 7 , dopamine 8 , DNA [9][10][11] , RNA 12,13 , enzyme and cancer biomarkers [14][15][16][17][18][19] , human hormones 20 , and cytokines 21,22 . These studies have demonstrated that NWFET-based biosensors represent a powerful detection platform for a broad range of biological and chemical species in a solution.…”

Electrochemical sensing of microRNAs: Avenues and paradigms

“…The developed assay allowed for the detection of miRNA levels down to 1 zeptomole (ca. 600 copies) in one minute (Lu et al, 2014). Table 2 summarizes the analytical performance of potentiometric, conductometric, impedimetric, and field-effect transistor-based biosensors currently employed for miRNA analysis.…”

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

“…An enhanced signalto-noise ratio (SNR; SNR > 20 for 1 fM DNA) was obtained, implying a detection floor of 50 aM. Next, they used this DNA-modified CMOS-compatible FET biosensor to measure miRNA molecules (Lu et al 2014). The nanosensor showed a rapid response of miR-21 and miR-205, with a low limit of detection of 1 zmol, and an excellent discrimination of single-nucleotide mismatched sequences.…”