Simultaneous trapping-and-detecting surface-enhanced Raman spectroscopy by self-aligned hot-spots

Soonwoo Hong, On Shim, Hyosung Kwon, Yeonho Choi

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

Abstract

Since surface-enhanced Raman spectroscopy (SERS) makes it possible to enhance weak Raman signals which represent molecular own vibrational transition as a fingerprint, it has gotten much attention in the field of biosensor. Although SERS can detect specific molecules with high sensitivity and selectivity, it is still difficult to fabricate efficient SERS substrates, align 'hot-spot' with a detection site, and increase reproducibility for molecular sensing. Here, we converged plasmonic trapping with conventional SERS in order to overcome these drawbacks. As plasmonic trapping is to move nano particles toward the desired position by electric field gradient, we could trap gold nano particles (GNPs) onto a raw bowtie substrate and fabricate self-aligned hot-spots by using plasmonic trapping, which is directly contributed to enhancing weak signals by shortening structure-to-structure distances. Also, since a united laser was used to trap GNPs and to detect target molecules at the same time, it was possible to directly obtain Raman signal on the self-aligned hotspots. To further verify our technique, we also conducted numerical analysis for electric field distribution and trapping force by using finite element method and the results were well matched with the experimental data. This increases low reproducibility of SERS and as a result, we could repetitively obtain same results.

Original languageEnglish
Title of host publicationPlasmonics in Biology and Medicine XIII
PublisherSPIE
Volume9724
ISBN (Electronic)9781628419580
DOIs
Publication statusPublished - 2016
EventPlasmonics in Biology and Medicine XIII - San Francisco, United States
Duration: 2016 Feb 152016 Feb 16

Other

OtherPlasmonics in Biology and Medicine XIII
CountryUnited States
CitySan Francisco
Period16/2/1516/2/16

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Keywords

  • biosensor
  • molecular sensing
  • plasmonic trapping
  • self-aligned hot-spots
  • surface-enhanced Raman spectroscopy (SERS)

ASJC Scopus subject areas

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

Cite this

Hong, S., Shim, O., Kwon, H., & Choi, Y. (2016). Simultaneous trapping-and-detecting surface-enhanced Raman spectroscopy by self-aligned hot-spots. In Plasmonics in Biology and Medicine XIII (Vol. 9724). [97240Y] SPIE. https://doi.org/10.1117/12.2214808