Nanocomposite TiO2/ZnO coated by copper (II) complex of di-Schiff bases with biological activity evaluation.

[Display omitted] • Nanocomposite of ZnO/TiO 2 coated by a mononuclear copper (II) di-Schiff base complex (Cu(LAm) 2) was synthesized. • Characterizations of ZnO/TiO 2 and Cu(LAm) 2 @ZnO/TiO 2) nanocomposites were investigated. • The antimicrobial reactivity were examined for both materials and their supports (HLAm and TiO 2 /ZnO). • DNA interaction was studied by electrophoresis technique. Treatment of 2-((4-hydroxybenzylidene)amino)phenol (HLAm) with Cu(II) ion of 2: 1 stoichiometric ratios, respectively, produced copper (II) di-Schiff base complex (Cu(LAm) 2). HLAm and Cu(LAm) 2 were characterized by using different spectroscopic tools (UV–Vis., IR, and mass spectra), and by CHN percentage analyses (EA). Cu(LAm) 2 was appended on the core/shell of zinc oxide and titanium oxide (TiO 2 /ZnO nanostructured species) within the deprotonated p -hydroxy group of the coordinated ligand. Various analytical tools were demonstrated to distinguish the internal structure and morphological features of the immobilized Cu-complex on TiO 2 /ZnO (Cu(LAm) 2 @TiO 2 /ZnO), as nanocomposite species using XRD, FESEM, HRTEM, IR and EDS spectra, furthermore with thermogravimetric analyses (TGA). TiO 2 was prepared from natural sources (Saussurea costus). For the therapeutic interest, the antimicrobial action of HLAm, Cu(LAm) 2 , TiO 2 /ZnO, Cu(LAm) 2 , and Cu(LAm) 2 @TiO 2 /ZnO against the growth of some common bacteria and fungi were examined. Cu(LAm) 2 and Cu(LAm) 2 @TiO 2 /ZnO displayed the highest action for the inhibition of their growth. The higher action of Cu(LAm) 2 and Cu(LAm) 2 @TiO 2 /ZnO over the free ligand HLAm and TiO 2 /ZnO core/shell was built on the behavior of Cu2+ ion in Schiff base coordination compound (Tweedy's chelation effect). Their reactivity with Genomic DNA was estimated within electrophoresis. As a biomedical candidate, Cu(LAm) 2 and the immobilized Cu(LAm) 2 on TiO 2 /ZnO nanoparticles could undergo further medicinal investigations according to the antimicrobial observations. [ABSTRACT FROM AUTHOR]