Signal-to-Noise Ratio Enhancement of Silicon Nanowires Biosensor with Rolling Circle Amplification

• DOI: 10.1021/nl401628y
• Publication Date: 2013-08-12T20:39:58Z
• Authors: Anran Gao; Nengli Zou; Pengfei Dai; Na Lu; Tie Li; Yuelin Wang; Jianlong Zhao; Hongju Mao
• Keywords: Rolling circle replication; Primer (cosmetics); Nanosensor

Herein, we describe a novel approach for rapid, label-free and specific DNA detection by applying rolling circle amplification (RCA) based on silicon nanowire field-effect transistor (SiNW-FET) the first time. Highly responsive SiNWs were fabricated with complementary metal oxide semiconductor (CMOS) compatible anisotropic self-stop etching technique which eliminated need hybrid method. The probe was immobilized surface of SiNW, followed sandwich hybridization perfectly matched target RCA primer that acted as to hybridize template. reaction created long single-stranded (ssDNA) product thus enhanced electronic responses SiNW significantly. signal-to-noise ratio (SNR) figure-of-merit analyzed estimate signal enhancement possible limit. nanosensor showed highly sensitive concentration-dependent conductance change in response sequences. Because binding an abundance repeated sequences products, SNR >20 1 fM achieved, implying floor 50 aM. This RCA-based biosensor also discriminated from one-base mismatched high selectivity due substantially reduced nonspecific onto through RCA. combination FET sensor will increase diagnostic capacity ability laboratories detect unexpected viruses, making it potential tool early diagnosis gene-related diseases.