Binding energies and hydrogen bonds effects on DNA-cisplatin interactions: a DFT-xTB study

Abstract

xTB and DFT-CAM-B3LYP were used to study hydrogen bonds in DNA base pairs and DNA-cisplatin complexes. Structure, binding energies and electron density are analyzed. xTB has proven to be an accurate method of obtaining structures and binding energies in DNA structures. Our xTB values for DNA base binding energy the pairs were in the same order and in some cases better than the CAM-B3LYP values compared to the experimental values. Double-stranded DNA-cisplatin structures have been calculated and the hydrogen bonds of water molecules are a decisive factor contribution to the preference for the cisplatin-Guanine interaction. Higher values of the water hydrogen binding energies were obtained in cisplatin-guanine structures. Furthermore, the electrostatic potential was used to investigate and improve the analyzes of the DNA-cisplatin structures.