Novel nanoparticle-size metal complexes derived from acyclovir. Spectroscopic characterization, thermal analysis, antitumor screening, and DNA cleavage, as well as 3D modeling, docking, and electrical conductivity studies

Abstract

Novel nano-sized Cr(III), Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes derived from acyclovir (ACV) were synthesized in different media. The synthesized metal complexes were characterized by different analytical and spectroscopic techniques. The ACV behaves as a bidentate (NO) chelating ligand. All complexes showed octahedral geometry, except Zn(II) complex which exhibited a tetrahedral geometry. The TGA results confirmed thermally stability of these complexes. The XRD patterns and TEM images indicated that the particles of the investigated complexes were situated in nano-scale range. The data obtained from the computational estimation agree well with the experimental results. The results of antimicrobial screening revealing enhancement in activity upon complex formation. All investigated compounds exhibited an inhibition of HEPG-2 cell growth. Additionally, the antitumor activity of the nano-scale complexes were enhanced after heating of them at 200 °C for 1 hour. The DNA cleavage study showed that the Cu(II) complex XXVII may be able to induce cellular death in cancer cells through apoptosis/necrosis pathways. The docking analysis revealed that the nano-sized Cu(II) complex V has stronger binding affinity to DNA than the free ligand ACV. Furthermore, the electrical conductivity measurements indicated that the ACV and its investigated nano-sized complexes behave as semiconductors, and the hopping model is applicable to describe the mechanism of conduction process.