The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Richard P Van Duyne - One of the best experts on this subject based on the ideXlab platform.

  • interaction of plasmon and molecular resonances for rhodamine 6g adsorbed on silver Nanoparticles
    Journal of the American Chemical Society, 2007
    Co-Authors: J Zhao, George C Schatz, Lasse Jensen, Jiha Sung, Shengli Zou, Richard P Van Duyne
    Abstract:

    Localized surface plasmon resonance (LSPR) is a key optical property of Metallic Nanoparticles. The peak position of the LSPR for Noble-Metal Nanoparticles is highly dependent upon the refractive i...

  • a unified view of propagating and localized surface plasmon resonance biosensors
    Analytical and Bioanalytical Chemistry, 2004
    Co-Authors: Amanda J Haes, Richard P Van Duyne
    Abstract:

    The intense colors of Noble Metal Nanoparticles have inspired artists and fascinated scientists for hundreds of years. In this review, we describe refractive index sensing platforms based on the tunability of the localized surface plasmon resonance (LSPR) of arrays of silver Nanoparticles and of single Nanoparticles. Specifically, the color associated with single Nanoparticles and surface-confined nanoparticle arrays will be shown to be tunable and useful as platforms for chemical and biological sensing. Finally, the LSPR nanosensor will be compared to traditional, flat surface, propagating surface plasmon resonance sensors.

  • a nanoscale optical biosensor the long range distance dependence of the localized surface plasmon resonance of Noble Metal Nanoparticles
    Journal of Physical Chemistry B, 2004
    Co-Authors: Amanda J Haes, George C Schatz, Shengli Zou, Richard P Van Duyne
    Abstract:

    The elucidation of the long range distance dependence of the localized surface plasmon resonance (LSPR) of surface-confined Noble Metal Nanoparticles is the aim of this work. It was suspected that the linear distance dependence found in CH3(CH2)xSH self-assembled monolayer (SAM) formation was the thin shell limit of a longer range, nonlinear dependence. To verify this, multilayer SAM shells based on the interaction of HOOC(CH2)10SH and Cu2+ were assembled onto surface-confined Noble Metal Nanoparticles and were monitored using UV−visible spectroscopy. Measurement of the LSPR extinction peak shift versus number of layers and adsorbate thickness is nonlinear and has a sensing range that is dependent on the composition, shape, in-plane width, and out-of-plane height of the Nanoparticles. Theoretical calculations based on an accurate electrodynamics description of the Metal nanoparticle plus surrounding layered material indicate plasmon resonance wavelength shifts that are in excellent agreement with the meas...

  • localized surface plasmon resonance immunoassay and verification using surface enhanced raman spectroscopy
    Proceedings of SPIE - The International Society for Optical Engineering, 2003
    Co-Authors: Chanda Ranjit Yonzon, Xiaoyu Zhang, Richard P Van Duyne
    Abstract:

    This work exploits the localized surface plasmon resonance (LSPR) spectroscopy of Noble Metal Nanoparticles to achieve sensitive and selective detection of biological analytes. Noble Metal Nanoparticles exhibit an LSPR that is strongly dependent on their size, shape, material, and the local dielectric environment. The LSPR is also responsible for the intense signals observed in surface-enhanced Raman scattering (SERS). Ag Nanoparticles fabricated using the nanosphere lithography (NSL) technique exploits this LSPR sensitivity as a signal transduction method in biosensing applications. The current work implements LSPR biosensing for the anti dinitrophenyl (antiDNP) immunoassay system. Upon forming the 2,4 dinitrobenzoic acid/antiDNP complex, this system shows a large LSPR shift of 44 nm when exposed to antiDNP concentration of 1.5 x 10-6 M. In addition, due to the unique molecular characteristics of the functional groups on the biosensor, it can also be characterized using SERS. First, the Nanoparticles are functionalized with a mixed self-assembled monolayer (SAM) comprised of 2:1 octanethiol and 11-amino undecanethiol. The SAM is exposed to 2,4-dinitrobenzoic acid with the 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride (EDC) coupling reagent. Finally, the 2,4-dinitrophenyl terminated SAM is exposed to various concentration of antiDNP. LSPR shifts indicate the occurrence of a binding event. SER spectra confirm binding of 2,4 dinitrobenzoic acid with amine-terminated SAM. This LSPR/SERS biosensing method can be generalized to a myriad of biologically relevant systems.

Hongjun Gao - One of the best experts on this subject based on the ideXlab platform.

  • monodisperse Noble Metal Nanoparticles and their surface enhanced raman scattering properties
    Chemistry of Materials, 2008
    Co-Authors: Chengmin Shen, Chao Hui, Tianzhong Yang, Congwen Xiao, J Tian, Lihong Bao, Shutang Chen, Hao Ding, Hongjun Gao
    Abstract:

    Monodisperse Au, Ag, and Au3Pd Nanoparticles (NPs) with narrow size distribution are prepared by direct reaction of the related Metal salt with oleylamine in toluene. Oleylamine serves as both a reducing agent and a surfactant in the synthesis. The sizes and shape of these NPs are tuned by reaction temperatures. The hydrophobic oleylamine-coated NPs can be made water soluble by replacing oleylamine with 3-mercaptopropionic acid. Both surface plasmonic resonance (SPR) and surface enhanced Raman scattering (SERS) observed from the Au and Ag NPs are found to be NP size- and surface-dependent.

Luis M Lizmarza - One of the best experts on this subject based on the ideXlab platform.

  • sensing using plasmonic nanostructures and Nanoparticles
    Nanotechnology, 2015
    Co-Authors: Judith Lange, Sergey M Novikov, Luis M Lizmarza
    Abstract:

    Nanoparticles are widely used in various fields of science and technology as well as in everyday life. In particular, gold and silver Nanoparticles display unique optical properties that render them extremely attractive for various applications. In this review, we focus on the use of Noble Metal Nanoparticles as plasmonic nanosensors with extremely high sensitivity, even reaching single molecule detection. Sensors based on plasmon resonance shifts, as well as the use of surface-enhanced Raman scattering and surface-enhanced fluorescence, will be considered in this work.

Amanda J Haes - One of the best experts on this subject based on the ideXlab platform.

  • a unified view of propagating and localized surface plasmon resonance biosensors
    Analytical and Bioanalytical Chemistry, 2004
    Co-Authors: Amanda J Haes, Richard P Van Duyne
    Abstract:

    The intense colors of Noble Metal Nanoparticles have inspired artists and fascinated scientists for hundreds of years. In this review, we describe refractive index sensing platforms based on the tunability of the localized surface plasmon resonance (LSPR) of arrays of silver Nanoparticles and of single Nanoparticles. Specifically, the color associated with single Nanoparticles and surface-confined nanoparticle arrays will be shown to be tunable and useful as platforms for chemical and biological sensing. Finally, the LSPR nanosensor will be compared to traditional, flat surface, propagating surface plasmon resonance sensors.

  • using solution phase Nanoparticles surface confined nanoparticle arrays and single Nanoparticles as biological sensing platforms
    Journal of Fluorescence, 2004
    Co-Authors: Amanda J Haes, Douglas A Stuart, Richard P Van Duyne
    Abstract:

    The intense colors of Noble Metal Nanoparticles have inspired artists and fascinated scientists for hundreds of years. In this review, we describe three sensing platforms based on the tunability of the localized surface plasmon resonance (LSPR) of gold and silver Nanoparticles. Specifically, the color associated with solution-phase Nanoparticles, surface-confined nanoparticle arrays, and single Nanoparticles will be shown to be tunable and useful as platforms for biological sensing.

  • a nanoscale optical biosensor the long range distance dependence of the localized surface plasmon resonance of Noble Metal Nanoparticles
    Journal of Physical Chemistry B, 2004
    Co-Authors: Amanda J Haes, George C Schatz, Shengli Zou, Richard P Van Duyne
    Abstract:

    The elucidation of the long range distance dependence of the localized surface plasmon resonance (LSPR) of surface-confined Noble Metal Nanoparticles is the aim of this work. It was suspected that the linear distance dependence found in CH3(CH2)xSH self-assembled monolayer (SAM) formation was the thin shell limit of a longer range, nonlinear dependence. To verify this, multilayer SAM shells based on the interaction of HOOC(CH2)10SH and Cu2+ were assembled onto surface-confined Noble Metal Nanoparticles and were monitored using UV−visible spectroscopy. Measurement of the LSPR extinction peak shift versus number of layers and adsorbate thickness is nonlinear and has a sensing range that is dependent on the composition, shape, in-plane width, and out-of-plane height of the Nanoparticles. Theoretical calculations based on an accurate electrodynamics description of the Metal nanoparticle plus surrounding layered material indicate plasmon resonance wavelength shifts that are in excellent agreement with the meas...

Chengmin Shen - One of the best experts on this subject based on the ideXlab platform.

  • monodisperse Noble Metal Nanoparticles and their surface enhanced raman scattering properties
    Chemistry of Materials, 2008
    Co-Authors: Chengmin Shen, Chao Hui, Tianzhong Yang, Congwen Xiao, J Tian, Lihong Bao, Shutang Chen, Hao Ding, Hongjun Gao
    Abstract:

    Monodisperse Au, Ag, and Au3Pd Nanoparticles (NPs) with narrow size distribution are prepared by direct reaction of the related Metal salt with oleylamine in toluene. Oleylamine serves as both a reducing agent and a surfactant in the synthesis. The sizes and shape of these NPs are tuned by reaction temperatures. The hydrophobic oleylamine-coated NPs can be made water soluble by replacing oleylamine with 3-mercaptopropionic acid. Both surface plasmonic resonance (SPR) and surface enhanced Raman scattering (SERS) observed from the Au and Ag NPs are found to be NP size- and surface-dependent.