Evaluating the Interaction between the Antineoplastic Drug Bexarotene and Double-stranded DNA Using Electrochemical, Spectroscopic, and Molecular Docking Studies

Abstract

Developing precise, quick, and affordable calf thymus double stranded deoxyribonucleic acid, ct-dsDNA, detection methods and understanding the structural alterations of ct-dsDNA following exposure to antineoplastic drugs is extraordinarily prominent. In this context, the destination of this search is to thrive an electrochemical ct-dsDNA biosensor to quantify bexarotene (BEX) and elucidate its DNA interaction mechanism. The interaction mechanism between DNA and BEX was analyzed by differential pulse voltammetry, fluorescence spectroscopy, and molecular docking analysis. The electrochemical experiment results indicated a significant interplay between BEX and ct-dsDNA, as seen by the reduced oxidation signals of deoxyadenosine (dAdo) and deoxyguanosine (dGuo) in the presence of BEX. The binding constant value (K_b) between ct-dsDNA and BEX was computed as 2.33×10⁴ L/mol at room temperature by using spectrofluorimetric measurements. Also, quantitative evaluation of thermodynamic data (ΔS = −10.24 cal mol⁻¹ K⁻¹ and ΔH = −18.17 kcal mol⁻¹ for BEX – ct-dsDNA complex predicted the contribution of van der Waals interplays and hydrogen bonds in the BEX–ct-dsDNA, as did molecular docking analysis. In molecular docking analysis, the binding energy of BEX with DNA is −7.2 kcal mol⁻¹, and it creates one powerful inter-molecular hydrogen bond besides van der Waals interactions.