A study of optical anisotropy for nearly spherical gold nanoparticles: Toward a sensitive detection using polarization microscopy in biomolecular applications

Bassam Al Qadi, Saiki Toshiharu

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

Anisotropic metal nanoparticles strongly change the scattered light polarization compared with isotropic nanoparticles, and this property can be utilized in a sensitive bimolecular recognition due to the high contrast that could be achieved in polarization microscopy. We report a study of the shape anisotropy in nearly spherical gold nanoparticles and particle dimers. It was obvious that each particle has its own scattering polarization dependence which reflects the relative changes in morphologies. Our experimental results reveal that particles with minimum anisotropy don't change the scattering light polarization which indicates their homogenous shape. Another particles show polarization dependence scattering intensity due to pronounced anisotropy. Particle dimers possess shape anisotropy that is characterized by a different polarizability for each axis in the nanostructure. We resolved the internal inhomogeneity in single particles and particle dimers using a qualitative analysis which enabled us to etermine the polarizabilities of both long and short axes for each particle and particle pair. A few of single particles show a strong optical anisotropy relative to their shape anisotropy, and even this observation was not yet clarified, it could be used in a sensitive bimolecular detection.

Original languageEnglish
Title of host publicationReporters, Markers, Dyes, Nanoparticles, and Molecular Probes for Biomedical Applications
PublisherSPIE
ISBN (Print)9780819474360
Publication statusPublished - 2009 Jan 1
EventReporters, Markers, Dyes, Nanoparticles, and Molecular Probes for Biomedical Applications - San Jose, CA, United States
Duration: 2009 Jan 262009 Jan 29

Publication series

NameProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume7190
ISSN (Print)1605-7422

Conference

ConferenceReporters, Markers, Dyes, Nanoparticles, and Molecular Probes for Biomedical Applications
CountryUnited States
CitySan Jose, CA
Period09/1/2609/1/29

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Keywords

  • Gold nanoparticles
  • Nanoparticle polarizability
  • Optical anisotropy
  • Polarization microscopy

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Atomic and Molecular Physics, and Optics
  • Radiology Nuclear Medicine and imaging

Cite this

Qadi, B. A., & Toshiharu, S. (2009). A study of optical anisotropy for nearly spherical gold nanoparticles: Toward a sensitive detection using polarization microscopy in biomolecular applications. In Reporters, Markers, Dyes, Nanoparticles, and Molecular Probes for Biomedical Applications [719016] (Progress in Biomedical Optics and Imaging - Proceedings of SPIE; Vol. 7190). SPIE.