Iron(III), Chromium(III), and Copper(II) Complexes of l-Norvaline and Ferulic Acid
journal contributionposted on 10.03.2011, 00:00 by Artik Elisa Angkawijaya, Ahmed E. Fazary, Erzalina Hernowo, Mohamed Taha, Yi-Hsu Ju
The complexation equilibria of l-norvaline (Nva) and ferulic acid (FA) were studied in aqueous solutions at room temperature (298 K) and in fixed ionic strength (0.15 mol·dm−3 NaNO3) by means of potentiometry and spectrophotometry techniques. The ferric (Fe3+), chromium (Cr3+), and cupric (Cu2+) complexing capacities of Nva and FA and their overall stability constants in aqueous solutions were obtained by the HYPERQUAD 2008 program from the potentiometric data. The concentration distributions of the various complex specia in solution were evaluated and discussed. The spectroscopic UV−visible measurements are carried out to give qualitative information about the confirmation of the complexes formed in these solutions.