Nickel and Cobalt Complexes of Non-protein L-Norvaline and Antioxidant Ferulic Acid: Potentiometric and Spectrophotometric Studies

作者：Angkawijaya Artik Elisa; Fazary Ahmed E; Hernowo Erzalina; Ismadji Suryadi; Ju Yi Hsu^*

来源：Journal of Solution Chemistry, 2012, 41(7): 1156-1164.

DOI：10.1007/s10953-012-9861-0

• L-norvaline
• Ferulic acid
• Complexation
• Equilibria

Binary and mixed-ligand complexes of Ni2+ and Co2+ involving L-norvaline (Nva) and ferulic acid (FA) have been investigated in aqueous solutions by pH potentiometry and UV-visible spectrophotometric techniques, at 298.15 K and fixed ionic strength (0.15 mola %26lt;...dm(-3), NaNO3). The overall stability constants of the Ni2+ and Co2+ complexes with the ligands studied were obtained by the HYPERQUAD2008 program from the pH-potentiometric data. As a result of the numerical treatment, a model composed of seven species NiNva(+), NiNva(2), NiNvaH(-1), , NiFA, and NiNvaFA(-) was obtained for the Ni2++Nva+FA system, whereas for the Co2++Nva+FA system the complexes CoNva(+), CoNva(2), CoNvaH(-1), , CoFA, , and CoNvaFA(-) were obtained. The complex species distributions in certain pH ranges were calculated by the HySS2009 simulation program. Spectroscopic UV-visible measurements were carried out to give qualitative information about the complexes formed in these solutions.

• 出版日期2012-8