Size-dependent plasmonic responses of single gold nanoparticles for analysis of biorecognition

Woo Sung Hwang, Phuoc Long Truong, Sang Jun Sim

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

We report the use of plasmonic responses of single gold nanoparticles (AuNPs) with various sizes for the analysis of biomolecular recognition. We also describe the relationship between particle size and plasmonic response induced by the binding of receptors and target analytes. To investigate the plasmonic response of AuNPs, Rayleigh light scattering spectra were collected from individual AuNPs using a dark-field microspectroscopy system. Using prostate-specific antigen (PSA) as a model, the linear dynamic range was obtained in the concentration range of 10 -4 to 10 ng/ml, with the smallest detectable concentration at 0.1 pg/ml corresponding to localized surface plasmon resonance (LSPR) λ max shifts of approximately 2.95 nm. This result indicates that individual AuNPs can be used for development of a very sensitive, robust, simple, and label-free biosensor to detect protein biomarkers. Furthermore, the method possesses great potential for monitoring other biological interactions.

Original languageEnglish
Pages (from-to)213-218
Number of pages6
JournalAnalytical Biochemistry
Volume421
Issue number1
DOIs
Publication statusPublished - 2012 Feb 1

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Keywords

  • Biomolecular recognition
  • Gold nanoparticle (AuNP)
  • Localized surface plasmon resonance (LSPR)
  • Resonant Rayleigh light scattering

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

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