Related Experiment Video
Updated: Apr 23, 2026

Author Spotlight: Characterizing DNA G-Quadruplex by Bis-3-Chloropiperidine Based Chemical Mapping
Published on: May 12, 2023
Spectral properties and thermal stability of AS1411 G-quadruplex
Zeinab Bagheri1, Bijan Ranjbar2, Hamid Latifi3
1Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
Abstract:
G-quadruplexes are supramolecular structures of G-rich nucleic acid, formed by non-canonical base pairing in the presence of specific environmental inducers. These structures have been vastly considered in diagnostic and therapeutic applications. However, detailed information on structure, optical properties and thermal stability of G-quadruplex potent oligonucleotides is scarce. Herein, optical properties and thermodynamic stability of AS1411 quadruplex is reported for various concentrations of potassium and lead ions. Circular dichroism showed that AS1411 ss-DNA folds into parallel conformation in the presence of metal ions and molecular crowding condition. UV-vis spectroscopy indicated formation of quadruplex and fluorescent spectroscopy revealed intercalation of PicoGreen in its structure, with enhancement of emission intensity upon increment of metal ion concentration. This investigation also proposes high-throughput and reliable analysis of AS1411 quadruplex's thermal stability by real-time PCR technique, which can be further applied for other quadruplex structures.
Related Concept Videos
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
UV–Vis Spectroscopy: Molecular Electronic Transitions

