Monitoring Early-Stage Nanoparticle Assembly in Microdroplets by Optical Spectroscopy and SERS

Andrew R. Salmon, Ruben Esteban, Richard W. Taylor, James T. Hugall, Clive A. Smith, Graeme Whyte, Oren A. Scherman, Javier Aizpurua, Chris Abell, Jeremy J. Baumberg

Research output: Contribution to journalArticle

14 Citations (Scopus)
44 Downloads (Pure)

Abstract

Microfluidic microdroplets have increasingly found application in biomolecular sensing as well as nanomaterials growth. More recently the synthesis of plasmonic nanostructures in microdroplets has led to surface-enhanced Raman spectroscopy (SERS)-based sensing applications. However, the study of nanoassembly in microdroplets has previously been hindered by the lack of on-chip characterization tools, particularly at early timescales. Enabled by a refractive index matching microdroplet formulation, dark-field spectroscopy is exploited to directly track the formation of nanometer-spaced gold nanoparticle assemblies in microdroplets. Measurements in flow provide millisecond time resolution through the assembly process, allowing identification of a regime where dimer formation dominates the dark-field scattering and SERS. Furthurmore, it is shown that small numbers of nanoparticles can be isolated in microdroplets, paving the way for simple high-yield assembly, isolation, and sorting of few nanoparticle structures.

Original languageEnglish
Pages (from-to)1788–1796
Number of pages9
JournalSmall
Volume12
Issue number3
Early online date10 Feb 2016
DOIs
Publication statusPublished - 6 Apr 2016

Keywords

  • Dark-field spectroscopy
  • Microdroplets
  • Nanoparticle
  • SERS

ASJC Scopus subject areas

  • Biomaterials
  • Engineering (miscellaneous)
  • Biotechnology

Fingerprint Dive into the research topics of 'Monitoring Early-Stage Nanoparticle Assembly in Microdroplets by Optical Spectroscopy and SERS'. Together they form a unique fingerprint.

  • Cite this

    Salmon, A. R., Esteban, R., Taylor, R. W., Hugall, J. T., Smith, C. A., Whyte, G., Scherman, O. A., Aizpurua, J., Abell, C., & Baumberg, J. J. (2016). Monitoring Early-Stage Nanoparticle Assembly in Microdroplets by Optical Spectroscopy and SERS. Small, 12(3), 1788–1796. https://doi.org/10.1002/smll.201503513