Selective, pH-Dependent Colorimetric and Fluorimetric Detection of Quadruplex DNA with 4-Dimethylamino(phenyl)-Substituted Berberine Derivatives.

ABSTRACT: The 9- and 12-dimethylaminophenyl-substituted berberine derivatives 3 a and 3 b were readily synthesized by Suzuki-Miyaura reactions and shown to be useful fluorescent probes for the optical detection of quadruplex DNA (G4-DNA). Their association with the nucleic acids was investigated by spectrometric titrations, CD and LD spectroscopy, and with DNA-melting analysis. Both ligands bind to duplex DNA by intercalation and to G4-DNA by terminal π stacking. At neutral conditions, they bind with higher affinity (K_b =10⁵ -10⁶  M^-1 ) to representative quadruplex forming oligonucleotides 22AG, c-myc, c-kit, and a2, than to duplex calf thymus (ct) DNA (K_b =5-7×10⁴  M^-1 ). At pH 5, however, the affinity of 3 a towards G4-DN

SUBMITTER: Wickhorst PJ 

PROVIDER: S-EPMC8252107 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature