Green synthesis of biologically active transition metal nanoparticles containing novel Schiff base via catalyst free hydrothermal reaction: Structural, biological and morphology study

Novel cobalt, nickel and copper complexes were synthesized by regular reflux method and nano sized Co(II), Ni(II) and Cu(II) metal complexes were synthesized by a facile hydrothermal method using green solvent at various temperatures without the addition of any capping agent. The structural characterization was done by magnetic susceptibility, molar conductance, elemental analysis, thermal analysis, FT‐IR, 1H NMR, 13C NMR, ESI mass, UV–Visible analysis. The morphology and size of the nano metal complexes were determined using FE‐Scanning electron microscopy, powder X‐ray diffraction data and atomic force microscopic techniques. All the spectral and analytical results reveal 1:2 metal to ligand ratios having [ML2(H2O)2] stoichiometry, here M=Co(II), Ni(II) and Cu(II), L=deprotonated ligand. The non‐electrolytic nature of the compound was confirmed by molar conductance experiment. The synthesized Schiff base and its metal complexes (7, 8 and 9) were tested for their biological activity. All the tested compounds exhibit decent anticancer and DNA cleavage activity and copper complex shows better activity results than other tested compounds. Nano sized late first row transition metal complexes was synthesized via reflux and hydrothermal method and selected compounds have been used as potent drugs against tested assays.