Spectrophotometric studies for the interaction of As+3 ion with some chelators

M. Al-Rufaie, Elham.; D. Fahad, Fahad

	Spectrophotometric studies for the interaction of As+3 ion with some chelators
journal of kerbala university
Article 1, Volume 11, Issue 2, 2015, Pages 43-57 PDF (0 K)
Authors
Elham. M. Al-Rufaie; Fahad D. Fahad
Abstract
Arsenic is one of the toxic heavy metal when presented in a high level over it allowable limit. To detoxify this heavy metal a chelators were used as in a chelation therapy. This work studies the complexation of some chelators (EDTA, penicillamine, genistein and qurecetin) with As III ion. A spectrophotometric techniques were applied in water and water-ethanol mixture as a solvent, at four different temperature. A shift in it max and decrease in absorbance indicating the complex formation. The stoichiometry of these complexes were determined by a method of the continuous variation (Job's) method, it was found that As-EDTA were (2:1), As-gensitein and As-quercetin (1:1), and As-penicillamine (1:2). These chelator's have a high tendency to complex with As III ion which were reflected by its high values of their equilibrium constants. Thermodynamic parameters indicate a spontaneous interaction (negative free energy change Go), and the enthalpy changr for As-gensitein complex were positive and the other three complexes have negative Ho which depends on type of the interaction and the structures of the complexes. The kinetic calculations shows a second order interaction.
Keywords
Chelating agents; EDTA; penicillamine; genistein; qurecetine; kinetic parameters; thermodynamic parameters and complexation

Statistics Article View: 227 PDF Download: 64