A two-color-change, nanoparticle-based method for DNA detection

Y. Charles Cao, Rongchao Jin, C. Shad Thaxton, Chad A. Mirkin*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

103 Scopus citations


Herein, we describe the detailed synthesis of Ag/Au core-shell nanoparticles, the surface-functionalization of these particles with thiolated oligonucleotides, and their subsequent use as probes for DNA detection. The Ag/Au core-shell nanoparticles retain the optical properties of the silver core and are easily functionalized with thiolated oligonucleotides due to the presence of the gold shell. As such, the Ag/Au core-shell nanoparticles have optical properties different from their pure gold counterparts and provide another "color" option for target DNA-directed colorimetric detection. Size-matched Ag/Au core-shell and pure gold nanoparticles perform nearly identically in DNA detection and melting experiments, but with distinct optical signatures. Based on this observation, we report the development of a two-color-change method for the detection and simultaneous validation of single-nucleotide polymorphisms in a DNA target using Ag/Au core-shell and pure gold nanoparticle probes.

Original languageEnglish (US)
Pages (from-to)449-455
Number of pages7
Issue number3
StatePublished - Sep 15 2005


  • Core-shell
  • Detection
  • Nanoparticles
  • Oligonucleotides
  • Two-color-change

ASJC Scopus subject areas

  • Analytical Chemistry


Dive into the research topics of 'A two-color-change, nanoparticle-based method for DNA detection'. Together they form a unique fingerprint.

Cite this