title: Real-time label-free immunoassay of interferon-gamma and prostate-specific antigen using a Fiber-Optic Localized Surface Plasmon Resonance sensor.
abstract: A Fiber-Optic Localized Surface Plasmon Resonance (FO LSPR) sensor was fabricated using spherical gold nanoparticles (Au NPs) on a flattened end-face of the optical fiber. The Au NPs were easily synthesized by the Turkevich method and were immobilized on the end-face of the optical fiber by using a self-assembled monolayer (SAM). In order to examine the possibility of its application as a biosensor for label-free immunoassays, the fabricated FO LSPR sensor was used for the detection of the antibody-antigen reaction of interferon-gamma (IFN-γ) and the limit of detection (LOD) was approximately 2pg/ml. Herein, The antibodies and bovine serum albumins (BSAs) were immobilized on the Au NPs by physisorption. Also, the FO LSPR sensor was used for the detection of a prostate-specific antigen (PSA) and the LOD was 1pg/ml below. The fabricated FO LSPR sensor can be used for real-time label-free immunoassay having fast detection time, high resolution and sensitivity. In addition, the proposed sensor platform has the advantages of low cost, simple optical setup, remote sensing, simple fabrication, real-time detection, low sample volume, and potential application to in-vivo detection systems.
authors.affiliation: Department of Nuclear Medicine, SNU College of Medicine, Institute of Radiation Medicine, SNUMRC, 28 Yongon-Dong, Chongno-Gu, Seoul 110-799, Republic of Korea. korea323@hotmail.com
authors.forename: Hyeon-Ho
authors.initials: HH
authors.lastname: Jeong
authors.forename: Norov
authors.initials: N
authors.lastname: Erdene
authors.forename: Jae-Hyoung
authors.initials: JH
authors.lastname: Park
authors.forename: Dae-Hong
authors.initials: DH
authors.lastname: Jeong
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Lee
authors.forename: Seung-Ki
authors.initials: SK
authors.lastname: Lee
mesh_terms: D055910:Antibodies, Immobilized / Q000276:immunology; D000937:Antigen-Antibody Reactions; D004867:Equipment Design; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation*; D007371:Interferon-gamma / Q000032:analysis* / Q000276:immunology; D057230:Limit of Detection; D008297:Male; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000276:immunology; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D055910:Antibodies, Immobilized; D006046:Gold; D007371:Interferon-gamma; D017430:Prostate-Specific Antigen