TY - JOUR
T1 - Effect of dielectric spacer thickness on signal intensity of surface plasmon field-enhanced fluorescence spectroscopy
AU - Murakami, Takashi
AU - Arima, Yusuke
AU - Toda, Mitsuaki
AU - Takiguchi, Hiromi
AU - Iwata, Hiroo
N1 - Funding Information:
This study was partly supported by a project within the Kyoto City Collaboration of Regional Entities for the Advancement of Technological Excellence (CREATE) and partly by the Development of Systems and Technology for Advanced Measurement and Analysis, assigned by the Japan Science and Technology Agency (JST).
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2012/2/15
Y1 - 2012/2/15
N2 - Surface plasmon field-enhanced fluorescence spectroscopy (SPFS) combines enhanced field platform and fluorescence detection. Its advantages are the strong intensity of the electromagnetic field and the high signal/noise (S/N) ratio due to the localized evanescent field at the water/metal interface. However, the energy transfer from the fluorophore to the metal surface diminishes the fluorescence intensity, and this reduces the sensitivity. In this study, we tested whether polystyrene (PSt) could act as a dielectric layer to suppress the energy transfer from the fluorophore to the metal surface. We hypothesized that this would improve the sensitivity of SPFS-based immunoassays. We used α-fetoprotein (AFP) as a model tumor biomarker in the sandwich-type immunoassay. We determined the relationship between fluorescent signal intensity and PSt layer thickness and compared this to theoretical predictions. We found that the fluorescence signal increased by optimally controlling the thickness of the PSt layer. Our results indicated that the SPFS-based immunoassay is a promising clinical diagnostic tool for quantitatively determining the concentrations of low-level biomarkers in blood samples.
AB - Surface plasmon field-enhanced fluorescence spectroscopy (SPFS) combines enhanced field platform and fluorescence detection. Its advantages are the strong intensity of the electromagnetic field and the high signal/noise (S/N) ratio due to the localized evanescent field at the water/metal interface. However, the energy transfer from the fluorophore to the metal surface diminishes the fluorescence intensity, and this reduces the sensitivity. In this study, we tested whether polystyrene (PSt) could act as a dielectric layer to suppress the energy transfer from the fluorophore to the metal surface. We hypothesized that this would improve the sensitivity of SPFS-based immunoassays. We used α-fetoprotein (AFP) as a model tumor biomarker in the sandwich-type immunoassay. We determined the relationship between fluorescent signal intensity and PSt layer thickness and compared this to theoretical predictions. We found that the fluorescence signal increased by optimally controlling the thickness of the PSt layer. Our results indicated that the SPFS-based immunoassay is a promising clinical diagnostic tool for quantitatively determining the concentrations of low-level biomarkers in blood samples.
UR - http://www.scopus.com/inward/record.url?scp=84859713199&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84859713199&partnerID=8YFLogxK
U2 - 10.1016/j.ab.2011.12.008
DO - 10.1016/j.ab.2011.12.008
M3 - Article
C2 - 22226791
AN - SCOPUS:84859713199
VL - 421
SP - 632
EP - 639
JO - Analytical Biochemistry
JF - Analytical Biochemistry
SN - 0003-2697
IS - 2
ER -