Journal
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
Volume 61, Issue 9, Pages 1985-1990Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.saa.2004.07.029
Keywords
flavonoids; Al(III) and Zn(II) complexes; spectral and electrochemical properties
Categories
Ask authors/readers for more resources
The synthesis, electrochemical and spectral (UV-vis, H-1 NMR, IR, fluorescence) properties as well as thermal behaviors of Al(III) and Zn(II) complexes with the flavonoids quercetin (H2L1), rutin (H2L2) and galangin (HL3) are presented. The complexes may be formulated as [Al-2(L-1)(H2O)(8)]Cl-4, [Al-3(L-2)(2)(H2O)(12)]Cl-5, [Al(L-3)((HO)-O-2)(4)]Cl-2, [Zn-2(L-1)(H2O)(4)]Cl-2, [Zn-3(L-2)(2)(H2O)(6)]Cl-2 and [Zn(L-3)(H2O)(2)]Cl. The higher fluorescence intensities of the complexes related to the free flavonoids, are attributed to the coordination of the ligands to the small, highly charged Al(III) and Zn(II) ions. The coordination effectively increases the rigidity of the ligand structure and increases the fluorescence quantum yield by reducing the probability of non-radiative energy dissipation process. Antioxidant activities of the compounds were also investigated under an electrochemical point of view. The cyclic voltammetric data show a considerable decrease of the oxidation potentials of the complexes related to that of the free flavonoids. Thus, the flavonoid-metal complexes are more effective antioxidants than the free flavonoids. (c) 2004 Elsevier B.V All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available