title: Detection of aquaporin-4 antibody using aquaporin-4 extracellular loop-based carbon nanotube biosensor for the diagnosis of neuromyelitis optica.
abstract: Here we propose a carbon nanotube (CNT) field-effect transistor (FET) functionalized with aquaporin-4 (AQP4) extracellular loop peptides for the rapid detection of AQP4 antibody without pretreatment. Neuromyelitis optica (NMO) is a rare disease of the central nerve system that affects the optic nerves and the spinal cord. NMO-IgG, a serum antibody in patients, is highly specific for NMO and targets AQP4. We synthesized AQP4 extracellular loop peptides, known as primary autoimmune target in NMO, and immobilized them onto CNT-FET. The sensor showed p-type FET characteristics after the functionalization of peptides. The sensor was able to detect antibody with a detection limit of 1 ng l(-1). Moreover, AQP4 antibody in human serum was detected without any pretreatment. These results indicate that the biosensor can be used for rapid and simple detection of NMO antibody.
authors.affiliation: Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Manki
authors.initials: M
authors.lastname: Son
authors.affiliation: Department of Biophysics and Chemical Biology, Seoul National University, Seoul 151-747, South Korea.
authors.forename: Daesan
authors.initials: D
authors.lastname: Kim
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital, Seoul 110-744, South Korea.
authors.forename: Kyung Seok
authors.initials: KS
authors.lastname: Park
authors.affiliation: Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University, Seoul 151-747, South Korea. Electronic address: seunghun@snu.ac.kr.
authors.forename: Seunghun
authors.initials: S
authors.lastname: Hong
authors.affiliation: Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 151-742, South Korea; School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742, South Korea; Advanced Institutes of Convergence Technology, Suwon 433-270, South Korea. Electronic address: thpark@snu.ac.kr.
authors.forename: Tai Hyun
authors.initials: TH
authors.lastname: Park
mesh_terms: D000906:Antibodies / Q000276:immunology / Q000302:isolation & purification*; D051401:Aquaporin 4 / Q000276:immunology / Q000302:isolation & purification*; D015374:Biosensing Techniques / Q000379:methods*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D037742:Nanotubes, Carbon / Q000737:chemistry; D009471:Neuromyelitis Optica / Q000097:blood* / Q000276:immunology
chemical_list: D000906:Antibodies; D051401:Aquaporin 4; D007074:Immunoglobulin G; D037742:Nanotubes, Carbon
keywords: Aquaporin-4; Carbon nanotube; Field-effect transistor; Neuromyelitis optica