"Molecular beacon"-hosted thioflavin T: Applications for label-free fluorescent detection of iodide and logic operations

Talanta. 2016 Apr 1:150:615-21. doi: 10.1016/j.talanta.2016.01.003. Epub 2016 Jan 4.

Abstract

In this work, we presented a simple, label-free and rapid-responsive fluorescence assay for iodide (I(-)) detection based on "molecular beacon (MB)"-hosted thioflavin T (ThT), achieving a limit of detection as low as 158 nM. The proposed method exhibited very good selectivity to I(-) ions over other anions interference due to the strong binding force between I(-) ions with Hg(2+). Upon the addition of I(-) ions, it would capture Hg(2+) from a T-Hg(2+)-T complex belonging to the MB-like DNA hairpin structure, which eventually quenched the initial fluorescence as output. In addition, it was successfully applied for operation of an integrated DNA logic gate system and to the determination of I(-) in real samples such as human urine.

Keywords: DNA; Iodide; Logic gate; Molecular beacon; Thioflavin T.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzothiazoles
  • Biosensing Techniques / methods*
  • DNA / chemistry*
  • Fluorescent Dyes / chemistry*
  • Humans
  • Iodides / urine*
  • Mercury / chemistry*
  • Spectrometry, Fluorescence / methods*
  • Thiazoles / chemistry*

Substances

  • Benzothiazoles
  • Fluorescent Dyes
  • Iodides
  • Thiazoles
  • thioflavin T
  • DNA
  • Mercury