A HIGHLY SENSITIVE RESONANCE SCATTERING SPECTRAL ASSAY FOR Hg2+ BASED ON THE APTAMER-MODIFIED AuRu NANOPARTICLE-NaClO3-NaI-CATIONIC SURFACTANT CATALYTIC REACTION

Gold ruthenium (AuRu) nanoparticles were modified by single strand DNA (ssDNA) to prepare an aptamer AuRu nanoprobe (AuRussDNA) for Hg2+. The nanoprobe reacted with Hg2+ to form double-stranded T-Hg2+-T mismatches, and the released AuRu nanoparticles aggregated to big particles, which induced an increase in the resonance scattering (RS) signal at 592 nm. The RS signal was linear to the concentration of Hg2+ in the range of 0.0067-3.3 nmol L-1. Using the AuRussDNA in filtration solution as a catalyst, a new catalytic RS assay was proposed for detection of trace Hg2+. This method was applied for the determination of Hg2+ in real samples.