Development of a new colorimetric and red-emitting fluorescent dual probe for G-quadruplex nucleic acids

Abstract

A tailor-made colorimetric and red-emitting fluorescent dual probe for G-quadruplex nucleic acids was developed by incorporating a coumarin-hemicyanine fluorophore into an isaindigotone framework. The significant and distinct changes in both the color and fluorescence of this probe enable the label-free and visual detection of G-quadruplex structures.

Green and Red Fluorescent Dyes for Translational Applications in Imaging and Sensing Analytes: A Dual‐Color Flag

“…To detect G‐quadruplex structures, Yan and co‐workers have developed colorimetric probe 112 by merging thiazole orange into an isaindigotone framework (see Figure ); the sensitivity of the probe and its further application are restricted due to weak fluorescence emission. Building on this work, Yan and co‐workers have synthesized a similar probe, 113 , this time by merging a coumarin–hemicyanine fluorophore into the isaindigotone framework. Probe 113 is successful in detecting G‐quadruples structures, and a marked “turn‐on” effect in the fluorescence signal is observed.…”

Targeting G-quadruplex nucleic acids with heterocyclic alkaloids and their derivatives

“…In addition to being designed as potential anti-cancer drugs, the isaindigotone skeleton was also modified as a fluorescent probe for the detection of G-quadruplex structures. Incorporating thiazole orange (29) [99] or a coumarinehemicyanine fluorophore (30) [100] to the isaindigotone framework lead to a big leap from colorimetric probe to colorimetric and fluorescent dual probe for detecting Gquadruplexes. In another series of quinazolinone derivatives (31) recently reported to stabilize c-KIT G-quadruplex, the best compound 31e reduced the transcription of c-KIT by 52.5% and exhibited significant cytotoxicity in a gastrointestinal stromal tumor cell line [101].…”

Benzothiazole-substituted benzofuroquinolinium dyes as new fluorescent probes for G-quadruplex DNA

“…In order to demonstrate their molecular mechanism and functional significance, G-quadruplex detection is an important and challenging task [8]. Recently, some small molecular ligands, including cyanovinyl-pyridinium triphenylamine (CPY) [9], ISCH-1 [10], and squarylium dye TSQ1 [11], were employed as fluorescent probes for G-quadruplex detection. However, the detection systems and probes have some limitations and shortcomings in analytical practice, such as low selectivity, high background, and instable.…”