TY - GEN
T1 - Localized surface plasmon and molecular resonance
T2 - Plasmonics: Metallic Nanostructures and their Optical Properties IV
AU - Zhao, Jing
AU - Zhang, Xiaoyu
AU - Haes, Amanda J.
AU - Zou, Shengli
AU - Schatz, George C.
AU - Van Duyne, Richard P.
PY - 2006/11/30
Y1 - 2006/11/30
N2 - Localized surface plasmon resonance (LSPR) is one of the signature optical properties of noble metal nanoparticles. Since the LSPR wavelength λ max is extremely sensitive to the local environment, it allows us to develop nanoparticle-based LSPR chemical and biological sensors. In this work, we tuned the LSPR peaks of Ag nanotriangles and explored the wavelength-dependent LSPR shift upon the adsorption of some resonant molecules. The induced LSPR peak shifts (λ max) vary with wavelength and the line shape of the LSPR shift is closely related to the absorption features of the resonant molecules. When the LSPR of the nanoparticles directly overlaps with the molecular resonance, a very small LSPR shift was observed. An amplified LSPR shift is found when LSPR of the nanoparticles is at a slightly longer wavelength than the molecular resonance of the adsorbates. Furthermore, we apply the "amplified" LSPR shift to detect the substrate binding of camphor to the heme-containing cytochrome P450cam protiens (CYP101). CYP101 absorb light in the visible region. When a small substrate molecule binds to CYP101, the spin state of the molecule is converted to its low spin state. By fabricating nanoparticles with the LSPR close to the molecular resonance of CYP101 proteins, the LSPR response as large as -60 nm caused by the binding of small substrate has been demonstrated.
AB - Localized surface plasmon resonance (LSPR) is one of the signature optical properties of noble metal nanoparticles. Since the LSPR wavelength λ max is extremely sensitive to the local environment, it allows us to develop nanoparticle-based LSPR chemical and biological sensors. In this work, we tuned the LSPR peaks of Ag nanotriangles and explored the wavelength-dependent LSPR shift upon the adsorption of some resonant molecules. The induced LSPR peak shifts (λ max) vary with wavelength and the line shape of the LSPR shift is closely related to the absorption features of the resonant molecules. When the LSPR of the nanoparticles directly overlaps with the molecular resonance, a very small LSPR shift was observed. An amplified LSPR shift is found when LSPR of the nanoparticles is at a slightly longer wavelength than the molecular resonance of the adsorbates. Furthermore, we apply the "amplified" LSPR shift to detect the substrate binding of camphor to the heme-containing cytochrome P450cam protiens (CYP101). CYP101 absorb light in the visible region. When a small substrate molecule binds to CYP101, the spin state of the molecule is converted to its low spin state. By fabricating nanoparticles with the LSPR close to the molecular resonance of CYP101 proteins, the LSPR response as large as -60 nm caused by the binding of small substrate has been demonstrated.
KW - Cytochrome P450
KW - Discrete dipole approximation
KW - Kramers-Kronig transformation
KW - Localized surface plasmon resonance
KW - Molecular resonance
KW - Nanosphere lithography
KW - Substrate binding
UR - http://www.scopus.com/inward/record.url?scp=33751370149&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33751370149&partnerID=8YFLogxK
U2 - 10.1117/12.681423
DO - 10.1117/12.681423
M3 - Conference contribution
AN - SCOPUS:33751370149
SN - 0819464023
SN - 9780819464026
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Plasmonics
Y2 - 13 August 2006 through 16 August 2006
ER -