Highly reproducible immunoassay of cancer markers on a gold-patterned microarray chip using surface-enhanced Raman scattering imaging

Moonkwon Lee, Sangyeop Lee, Jung hwan Lee, Hyun woo Lim, Gi Hun Seong, Eun Kyu Lee, Soo Ik Chang, Chil Hwan Oh, Jaebum Choo

Research output: Contribution to journalArticle

98 Citations (Scopus)

Abstract

This paper reports a highly reproducible immunoassay of cancer markers using surface-enhanced Raman scattering (SERS) imaging. SERS is a highly sensitive detection method but it is limited in its ability to achieve reproducible signal enhancement because of the difficulty with precisely controlling the uniform distribution of hot junctions. Consequently, inconsistent enhancement prevents the wide exploitation of SERS detection as a bio-detection tool for quantitative analysis. To resolve this problem, we explored the use of a SERS imaging-based immunoassay. For this purpose, Raman reporter-labeled hollow gold nanospheres (HGNs), were manufactured and antibodies were immobilized onto their surfaces for targeting specific antigens. After the formation of sandwich immunocomplexes using these functional HGNs on the surfaces of gold patterned wells, the SERS mapping images were measured. For target protein markers, 12×9 pixels were imaged using a Raman mapping technique in the 0-10-4g/mL concentration range, and the SERS signals for 66 pixels were averaged. Here, the SERS imaging-based assay shows much better correlations between concentration and intensity than does the conventional point-based assay. The limits of detection were determined to be 0.1pg/mL and 1.0pg/mL for angiogenin (ANG) and alpha-fetoprotein (AFP), respectively. This detection sensitivity is increased by three or four orders of magnitude over that of conventional ELISA method. The detectable dynamic range for SERS imaging (10-4-10-12g/mL) is also much wider than that for ELISA (10-6-10-9g/mL).

Original languageEnglish
Pages (from-to)2135-2141
Number of pages7
JournalBiosensors and Bioelectronics
Volume26
Issue number5
DOIs
Publication statusPublished - 2011 Jan 15

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Keywords

  • Biomarker
  • Hollow gold nanosphere
  • Immunoassay
  • Microarray chip
  • Surface-enhanced Raman scattering imaging

ASJC Scopus subject areas

  • Biotechnology
  • Biophysics
  • Biomedical Engineering
  • Electrochemistry

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