Antimicrobial activity of copper (II) met al and nickel (II) metal complexes with schiff base ligand / Maisarah Shapie

The synthesized Schiff base ligand of 5-bromosalicylidene ethylenediamine (5-BrSalen), Cu (II) and Ni (II) metal complexes were successfully formed by undergoing condensation process. All compounds were then undergone some characterization studies by using melting point measurement, elemental analysis, infrared (FT-IR) and Ultraviolet-Visible (UV-Vis) spectroscopy. All compounds
were in a good percentage yield more than 80% and producing colours. Both Cu (II) and Ni (II) complexes were exhibited an emerald green colour and orange brown colour respectively to show that transition metals were used. The melting point of both metal complexes were greater than the free ligand. Elemental analysis
results have showed a good agreement with all the structures proposed with the correct compounds formulation. In FT-IR spectra, the presence of shifting
frequencies in C=N, C=C, C-O and C-N of metal complexes from the ligand indicated that ligand has coordinated to the metal ion. Meanwhile, UV-Vis spectra analysis has showed that rr ➔ rr* and n ➔ rr* types of transitions had presence in all synthesized compounds. An additional d-d transition type also was displayed for metal complexes due to coordination of ligand to metal ion at band above than 400nm. The synthesized ligand has showed good antimicrobial activity against E.coli bacteria compared to both metal complexes due to its negatively charged behavior compound.