title: Highly sensitive, label-free and real-time detection of alpha-fetoprotein using a silicon nanowire biosensor.
abstract: Alpha-fetoprotein (AFP) is a tumor-associated fetal protein that can be expressed in large amounts in adult tumor cells, serving as a useful clinical tumor-marker. Silicon nanowire (SiNW) biosensors have emerged as a powerful tool in detecting protein biomarkers, due to their ultrahigh sensitivity, real-time response and label-free detection. We fabricated a SiNW-based field-effect transistor (FET) according to "top-down" methodology. First, anti-AFP antibodies were immobilized onto the surface of the SiNW-FET. A polydimethylsiloxane (PDMS) microchannel was then integrated to the modified SiNW-FET. Various concentrations of AFP were then pumped through the sensing area. We observed a current change that corresponded to binding of AFP onto the surface of our anti-AFP functionalized SiNW-FET biosensor. Concentrations of AFP as low as 0.1 ng/mL were detected. The results implicate our SiNW biosensor as an effective AFP biomarker detector with promising potential in clinical applications.
authors.affiliation: a Department of Endoscopy Surgery , Wuxi People's Hospital Affiliated to Nanjing Medical University , Wuxi , P. R. China.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhou
authors.forename: Zengyao
authors.initials: Z
authors.lastname: Li
authors.forename: Zengtao
authors.initials: Z
authors.lastname: Bao
authors.forename: Kang
authors.initials: K
authors.lastname: Feng
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhang
authors.forename: Tong
authors.initials: T
authors.lastname: Wang
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis* / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation*; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D056656:Lab-On-A-Chip Devices; D055616:Microtechnology; D053770:Nanowires; D012680:Sensitivity and Specificity; D012825:Silicon / Q000737:chemistry*; D014173:Transistors, Electronic; D000509:alpha-Fetoproteins / Q000032:analysis* / Q000737:chemistry
chemical_list: D014408:Biomarkers, Tumor; D004129:Dimethylpolysiloxanes; D000509:alpha-Fetoproteins; C013830:baysilon; D012825:Silicon
keywords: Biosensors; microscopy; nanotechnology; point-of-care testing; proteins and enzymes