Open Chemistry Journal
2018, 5 : 158-171Published online 2018 December 24. DOI: 10.2174/1874842201805010158
Publisher ID: CHEM-5-158
RESEARCH ARTICLE
Preparation, Characterization and Antioxidant Evaluation of Cu(II) and Zn(II) Tannates
2 Department of Chemistry, Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso, Brazil
3 Institute of Chemistry, Federal University of Goiás (UFG), Goiânia, Goiás, Brazil
* Address correspondence to this author at the Department of Chemistry, Federal University of Mato Grosso (UFMT), Rua Consolação, n. 321, Coophema, Cuiabá, Mato Grosso, Brazil; Tel: 6584357708; E-mail: buzutti7@hotmail.com
ABSTRACT
Introduction:
The interest in the antioxidant materials increased due to their free radical scavenging properties avoiding various pathologies. Tannic Acid (TA) is known to have high free radical scavenging activity, but its application is still limited.
This paper had the objective of synthesis, characterization and evaluation of free radical scavenging activity of TA associated with Cu (II) and Zn (II) ions, in a buffered aqueous medium.
Methods and Materials:
Techniques of FTIR, simultaneous TG-DSC characterized the obtained compounds, and the evaluation of free radical scavenging activity was made using 2,2–diphenyl–1–picrylhydrazyl (DPPH) radical. The FTIR analysis of the compounds showed significant displacement of the main bands in the TA spectrum (νC=O, δO-H, σO-H), suggesting an association of metal ions with the oxygen of the hydroxyl group of TA. TG-DSC curves showed information about the thermal stability, stoichiometry, hydration water, and residues formation.
Results and Conclusion:
The TA association with the metal ions Cu(II) and Zn(II) decreased the antioxidant activity of the molecule significantly, showing that these compounds could be potentially used as pro-oxidant agents.