Surface plasmon resonance and surface plasmon field-enhanced fluorescence spectroscopy for sensitive detection of tumor markers.
Surface plasmon resonance (SPR), which provides real-time, in situ analysis of dynamic surface events, is a valuable tool for studying interactions between biomolecules. In the clinical diagnosis of tumor markers in human blood, SPR is applied to detect the formation of a sandwich-type immune complex composed of a primary antibody immobilized on a sensor surface, the tumor marker, and a secondary antibody. However, the SPR signal is quite low due to the minute amounts (ng-pg/mL) of most tumor markers in blood. We have shown that the SPR signal can be amplified by applying an antibody against the secondary antibody or streptavidin-conjugated nanobeads that specifically accumulate on the secondary antibody. Another method employed for highly sensitive detection is the surface plasmon field-enhanced fluorescence spectroscopy-based immunoassay, which utilizes the enhanced electric field intensity at a metal/water interface to excite a fluorophore. Fluorescence intensity attributed to binding of a fluorophore-labeled secondary antibody is increased due to the enhanced field in the SPR condition and can be monitored in real time.
Arima
Yusuke
Y
Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
Teramura
Yuji
Y
Takiguchi
Hiromi
H
Kawano
Keiko
K
Kotera
Hidetoshi
H
Iwata
Hiroo
H
D014408:Biomarkers, Tumor / Q000097:blood*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001774:Blood Chemical Analysis / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods; D009363:Neoplasm Proteins / Q000097:blood; D009369:Neoplasms / Q000097:blood* / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation* / Q000379:methods; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins