PLoS ONE (Jan 2013)

A label-free luminescent switch-on assay for ATP using a G-quadruplex-selective iridium(III) complex.

  • Ka-Ho Leung,
  • Lihua Lu,
  • Modi Wang,
  • Tsun-Yin Mak,
  • Daniel Shiu-Hin Chan,
  • Fung-Kit Tang,
  • Chung-Hang Leung,
  • Hiu-Yee Kwan,
  • Zhiling Yu,
  • Dik-Lung Ma

DOI
https://doi.org/10.1371/journal.pone.0077021
Journal volume & issue
Vol. 8, no. 10
p. e77021

Abstract

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We report herein the G-quadruplex-selective property of a luminescent cyclometallated iridium(III) complex for the detection of adenosine-5'-triphosphate (ATP) in aqueous solution. The ATP-binding aptamer was employed as the ATP recognition unit, while the iridium(III) complex was used to monitor the formation of the G-quadruplex structure induced by ATP. The sensitivity and fold enhancement of the assay were higher than those of the previously reported assay using the organic dye crystal violet as a fluorescent probe. This label-free luminescent switch-on assay exhibits high sensitivity and selectivity towards ATP with a limit of detection of 2.5 µM.