Spectral properties and dynamics of gold nanorods revealed by EMCCD-based spectral phasor method

Hongtao Chen, Enrico Gratton, Michelle A. Digman*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

Gold nanorods (NRs) with tunable plasmon-resonant absorption in the near-infrared region have considerable advantages over organic fluorophores as imaging agents due to their brightness and lack of photobleaching. However, the luminescence spectral properties of NRs have not been fully characterized at the single particle level due to lack of proper analytic tools. Here, we present a spectral phasor analysis method that allows investigations of NRs' spectra at single particle level showing the spectral variance and providing spatial information during imaging. The broad phasor distribution obtained by the spectral phasor analysis indicates that spectra of NRs are different from particle to particle. NRs with different spectra can be identified in images with high spectral resolution. The spectral behaviors of NRs under different imaging conditions, for example, different excitation powers and wavelengths, were revealed by our laser-scanning multiphoton microscope using a high-resolution spectrograph with imaging capability. Our results prove that the spectral phasor method is an easy and efficient tool in hyper-spectral imaging analysis to unravel subtle changes of the emission spectrum. We applied this method to study the spectral dynamics of NRs during direct optical trapping and by optothermal trapping. Interestingly, different spectral shifts were observed in both trapping phenomena. Microsc. Res. Tech. 78:283-293, 2015.

Original languageEnglish (US)
Pages (from-to)283-293
Number of pages11
JournalMicroscopy Research and Technique
Volume78
Issue number4
DOIs
StatePublished - Apr 1 2015
Externally publishedYes

Keywords

  • Gold nanorods
  • LSPR
  • Luminescence spectrum
  • Multiphoton excitation
  • Optical trapping
  • Optothermal trapping
  • Spectral phasor

ASJC Scopus subject areas

  • Anatomy
  • Histology
  • Instrumentation
  • Medical Laboratory Technology

Fingerprint Dive into the research topics of 'Spectral properties and dynamics of gold nanorods revealed by EMCCD-based spectral phasor method'. Together they form a unique fingerprint.

Cite this