A label-free G-quadruplex-based mercury detection assay employing the exonuclease III-mediated cleavage of T–Hg2+–T mismatched DNA

Abstract

We report herein the use of an exonuclease III and G-quadruplex probe to construct a G-quadruplex-based luminescence detection platform for Hg2+. Unlike common DNA-based Hg2+ detection methods, when using the dsDNA probe to monitor the hairpin formation, the intercalation of the dsDNA probe may be influenced by the distortion of dsDNA. This ‘mix-and-detect’ methodology utilized the G-quadruplex probe as the signal transducer and is simple, rapid, convenient to use and can detect down to 20 nM of Hg2+.

Keywords

• iridium(iii)
• exonuclease iii
• g-quadruplex
• mercury(ii) ion