Thermal studies and mass loss inhibition for some new mixed amino acid metal complexes with their applications

Abstract

A thermal gravimetric analysis was studied for the new metal mixed-ligand complexes of copper(II), nickel(II), cobalt(II), and zinc(II) metals formed with glutamic acid as a primary ligand and nitrilotriacetic acid (H3NTA) as a secondary ligand which have been characterized by their elemental analysis, magneto-chemical measurements, Fourier transform infrared (FTIR), UV–Vis spectrophotometer, thermal gravimetric analysis, and mass spectroscopy studies. Glutamic acid in these complexes acts as a bidentate ligand, coordinating through the one nitrogen of the amino group and one oxygen of the carboxylate group, whereas nitrilotriacetic acid shows a tridentate nature, and the coordination occurs through two carboxylate oxygen and one nitrogen of the amino group. Water molecules satisfy the remaining coordination positions. The complexes have been suggested to show geometry of an octahedral symmetry. The results were indicated that the mixed complexes were isolated in 1:1:1 molar ratio (metal–glutamic–HNTA), and the molecular structures were suggested to be [M(glutamic)(HNTA) (H2O)]·(2–1.5)H2O. The antimicrobial activities of our prepared complexes evaluated against Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus flavus (isolates from Micro-analytical Center, Faculty of Science, Cairo University) were investigated. Also, our prepared complexes were evaluated for their in vitro anticancer activity against hepatocellular carcinoma. In addition, the mass loss inhibition effects for copper and aluminum metal plates by our prepared complexes in 1 M HCl were studied.