Synthesis of a BODIPY-quinoline dyad probe and studies of its biophysical interactions with fibrinogen/HSA by spectral and computational methods

GÖKOĞLU E., Tekiz P., TEKNİKEL E., Doyuran B., TAŞKIN TOK T.

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY, vol.459, 2025 (SCI-Expanded, Scopus)

Abstract

A new BODIPY-based quinoline dyad probe (Bdq) was synthesized and its binding affinity with fibrinogen (Fib) and human serum albumin (HSA) was examined using steady-state/three-dimensional (3D) fluorescence and UV-vis absorption as well as molecular docking method. Fluorescence titration assays indicated that protein intrinsic emission was quenched by Bdq with a combined (static and dynamic) mechanism to form a nonfluorescent complex. 3D spectra showed that the two proteins undergo conformational changes when they interact with Bdq. Based on Forster's non-radiative energy transfer; r, binding distances were found as 3.64/3.47 nm for Fib/HSA. The negative values of both Delta H (-62.27 kJ/mol) and Delta S (-83.03 J/mol K) parameters pointed out van der Waals forces/hydrogen bonds with Fib and also positive values of both Delta H (240.0 kJ/mol) and Delta S (920.0 J/molK) showed hydrophobic interactions with HSA of Bdq. Molecular docking also gave consistent results supporting the experimental binding types.