Synthesis, characterization, luminescence and biological activities of lanthanide complexes with a hydrazone ligand

Five lanthanide [Ln(III) = Sm(III), Eu(III) Tb(III), Dy(III) & Yb(III)] complexes of N, N-bis (2-hydroxy-1-naphthylidene) isonicotinylhydrazone have been synthesized by following the complexation reaction between LnCl(3.6)H(2)O and hydrazone. The metal complexes were characterized by elemental analysis, molar conductance, UV-Visible, FTIR, mass spectroscopy, H-1 nuclear magnetic resonance, thermo gravimetric analysis, powder X-ray diffraction and fluorescence studies. Molar conductance data suggests that the synthesized lanthanide complexes posses non-electrolytic behaviour. The FTIR spectral data suggests that the ligand coordinated the lanthanide ion with deprotonation through carbonyl oxygen, azomethine nitrogen and naphtholic oxygen. Also, FTIR studies reveal that the lanthanide complexes contain coordinating mono ionic ligand. Powder X-ray diffraction studies reveal the lanthanide complexes are orthorhombic with different unit cell parameters. Europium, samarium, terbium, dysprosium and ytterbium complexes exhibit the characteristic luminescence. Further, the in vitro antimicrobial activity of the lanthanide complexes was performed and significant activity is observed against Eschereshia coli; Klebsiella; Staphylococcus aureus; Bacillus subtilis compared with the free ligand.