Label-Free, Electrical Detection of the SARS Virus N-Protein with Nanowire Biosensors Utilizing Antibody Mimics as Capture Probes

• Published in: ACS nano Vol. 3; no. 5; pp. 1219 - 1224
• Main Authors: Ishikawa, Fumiaki N, Chang, Hsiao-Kang, Curreli, Marco, Liao, Hsiang-I, Olson, C. Anders, Chen, Po-Chiang, Zhang, Rui, Roberts, Richard W, Sun, Ren, Cote, Richard J, Thompson, Mark E, Zhou, Chongwu
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 26.05.2009
• Subjects: Antibodies, Viral - chemistry; Biomimetic Materials - chemistry; Biosensing Techniques - instrumentation; Electrochemistry - instrumentation; Equipment Design; Fibronectins - immunology; Indium - chemistry; Macromolecular Substances - chemistry; Molecular Conformation; Nanostructures - chemistry; Nanostructures - ultrastructure; Nanotechnology - instrumentation; Particle Size; SARS coronavirus; Severe acute respiratory syndrome-related coronavirus - immunology; Severe acute respiratory syndrome-related coronavirus - isolation & purification; Staining and Labeling; Surface Properties; antibody mimetic protein; biosensor; nucleocapsid (N) protein; nanowire
• ISSN: 1936-0851; 1936-086X; 1936-086X
• DOI: 10.1021/nn900086c

Antibody mimic proteins (AMPs) are polypeptides that bind to their target analytes with high affinity and specificity, just like conventional antibodies, but are much smaller in size (2−5 nm, less than 10 kDa). In this report, we describe the first application of AMP in the field of nanobiosensors. In2O3 nanowire based biosensors have been configured with an AMP (Fibronectin, Fn) to detect nucleocapsid (N) protein, a biomarker for severe acute respiratory syndrome (SARS). Using these devices, N protein was detected at subnanomolar concentration in the presence of 44 μM bovine serum albumin as a background. Furthermore, the binding constant of the AMP to Fn was determined from the concentration dependence of the response of our biosensors.