Multiple label-free detection of antigen-antibody reaction using localized surface plasmon resonance-based core-shell structured nanoparticle layer nanochip.
In this research, a localized surface plasmon resonance (LSPR)-based bioanalysis method for developing multiarray optical nanochip suitable for screening bimolecular interactions is described. LSPR-based label-free monitoring enables to solve the problems of conventional methods that require large sample volumes and time-consuming labeling procedures. We developed a multiarray LSPR-based nanochip for the label-free detection of proteins. The multiarray format was constructed by a core-shell-structured nanoparticle layer, which provided 300 nanospots on the sensing surface. Antibodies were immobilized onto the nanospots using their interaction with Protein A. The concentrations of antigens were determined from the peak absorption intensity of the LSPR spectra. We demonstrated the capability of the array measurement using immunoglobulins (IgA, IgD, IgG, IgM), C-reactive protein, and fibrinogen. The detection limit of our label-free method was 100 pg/mL. Our nanochip is readily transferable to monitor the interactions of other biomolecules, such as whole cells or receptors, with a massively parallel detection capability in a highly miniaturized package. We anticipate that the direct label-free optical immunoassay of proteins reported here will revolutionize clinical diagnosis and accelerate the development of hand-held and user-friendly point-of-care devices.
Endo
Tatsuro
T
Department of Mechano-Micro Engineering, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama, 226-8502, Japan.
Kerman
Kagan
K
Nagatani
Naoki
N
Hiepa
Ha Minh
HM
Kim
Do-Kyun
DK
Yonezawa
Yuji
Y
Nakano
Koichi
K
Tamiya
Eiichi
E
D000937:Antigen-Antibody Reactions; D000941:Antigens / Q000032:analysis*; D002097:C-Reactive Protein / Q000737:chemistry; D005340:Fibrinogen / Q000737:chemistry; D007136:Immunoglobulins / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D040901:Proteomics / Q000295:instrumentation / Q000379:methods*; D020349:Surface Plasmon Resonance / Q000379:methods*
D000941:Antigens; D007136:Immunoglobulins; D005340:Fibrinogen; D002097:C-Reactive Protein