Analytical Spectral Studies of Nickel(II) and Palladium(II) Complexes with Selected Bidentate Ligands and their Biological Effects

Abstract

A new azo ligand was prepared by react N- (1-Naphthylethylenediamine dihydrochloride) with 4-nitroaniline and the resulting ligand was N- (2-(2-Amino 5-nitrophenyl) diazenyl) ethyl) naphthalen-1- amine. Complexes of Nickel(II) and palladium(II) were prepared with ligand N-(2-(2-Amino-5- nitrophenyl)diazenyl) ethyl)naphthalen-1- amine. Complexes were also prepared from mixed ligands as N- (2- (2-amino-5-nitrophenyl) diazenyl) ethyl) naphthalen-1-amine as a primary ligand with oxalic acid, malonic acid and sodium pyrophosphate as secondary ligands, the prepared complexes were characterization by spectroscopic methods (UV-Vis , FTIR, mass spectra, atomic absorption, elemental analysis, molar conductivity and magnetic sensitivity. Suggested molecular formulas of the prepared complexes: : . 1-]Ni(C18H17N5O2)Cl2[ 3-[Ni(C18H17N5O2)(Ma) [ 5-]Pd(C18H17N5O2)Cl2[ 7-]Pd(C18H17N5O2)(Ma)[ 2- ]Ni(C18H17N5O2)(Ox)[ 4- [Ni(C18H17N5O2)(pyph)] 6- ]Pd(C18H17N5O2)(Ox)[ 8-[Pd(C18H17N5O2)(pyph)] The molar conductivity results revealed that all of the complexes are non electrolytic, and the infrared spectrum revealed that all of the bidentate ligands are in coordination with the nickel(II) and palladium (II), The complexes were proposed to have square planar form based on the findings of magnetic susceptibility, massspectrometry, elemental analysis, and UV-Vis spectra . . . The study also includes finding a fast, easy and sensitive spectral method for estimating nickel(II) and palladium(II) using the detector N-(2-(2-Amino-5- nitrophenyl)..diazenyl)ethyl)naphthalen-1-amine . Spectrophotometry was taken for nickel(II) complexes at the wavelength equal to 574 nm and for palladium(II) complexes at the wavelength equal to 490 nm, optimum conditions were set. . . . Nickel(II) complex was given a linear relationship which obeys Beer- Lambert law at the concentrations (0.587-5.87) μg.ml-1 , with a correlation coefficient(R2 )equal to 0.9975, Molar absorptivity 676.4 L/ mol. cm at 574 nm, LOD 0.017 μg. mL-1 , LOQ 0.0561 μg. mL-1 , Sandell's sensitivity 0.087 μg. cm-2 , II % Recovery was (97.4-100)%, % Er (0.06-2.55)% and % RSD (1.193-2.278)%. . . Palladium(II) complex was given a linear relationship which obeys the Beer Lambert law at the concentrations (1.06-10.6) μg.mL-1 , with a correlation coefficient (R2 ) equal to 0.9958, Molar absorptivity 2067 L/ mol. cm at 490 nm, LOD 0.043 μg. mL-1 , LOQ 0.142 μg. mL-1 , Sandell's sensitivity 0.087 μg. cm-2 , % Recovery was (99.09-99.9)%, % Er (0.16-0.94)% and % RSD (0.655-1.626)%. The biological activity of the complexes was studied on two types of bacteria, [Staphylococcus aureus Gr+ve , Escherichia coli Gr-ve ], The minimum inhibitory concentration of the complexes was determined in a serial dilution, all nickel(II) complexes showed inhibition of the two types of bacteria at a concentration 1000 μg/mL, while some of palladium(II) complexes showed inhibition at a concentration equal to 1000 μg/ml.