Please use this identifier to cite or link to this item: https://www.arca.fiocruz.br/handle/icict/11955
Title: Norfloxacin Zn(II)-based complexes: acid base ionization constant determination, DNA and albumin binding properties and the biological effect against Trypanosoma cruzi
Authors: Gouvea, Ligiane R.
Martins, Darliane A.
Batista, Denise da Gama Jean
Soeiro, Maria de Nazaré C.
Louro, Sônia R. W.
Barbeira, Paulo J. S.
Teixeira, Letícia R.
Affilliation: Universidade Federal de Minas Gerais. Departamento de Química. Belo Horizonte, MG, Brasil.
Universidade Federal de Minas Gerais. Departamento de Química. Belo Horizonte, MG, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Celular. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Celular. Rio de Janeiro, RJ, Brasil.
Pontifícia Universidade Católica do Rio de Janeiro. Departamento de Fìsica.Rio de Janeiro, RJ, Brasil.
Universidade Federal de Minas Gerais. Departamento de Química. Belo Horizonte, MG, Brasil.
Universidade Federal de Minas Gerais. Departamento de Química. Belo Horizonte, MG, Brasil.
Abstract: Zn(II) complexes with norfloxacin (NOR) in the absence or in the presence of 1,10-phenanthroline (phen) were obtained and characterized. In both complexes, the ligand NOR was coordinated through a keto and a carboxyl oxygen. Tetrahedral and octahedral geometries were proposed for [ZnCl2(NOR)]H2O (1) and [ZnCl2(NOR)(phen)]2H2O (2), respectively. Since the biological activity of the chemicals depends on the pH value, pH titrations of the Zn(II) complexes were performed. UV spectroscopic studies of the interaction of the complexes with calf-thymus DNA (CT DNA) have suggested that they can bind to CT DNA with moderate affinity in an intercalative mode. The interactions between the Zn(II) complexes and bovine serum albumin (BSA) were investigated by steady-state and time-resolved fluorescence spectroscopy at pH 7.4. The experimental data showed static quenching of BSA fluorescence, indicating that both complexes bind to BSA. A modified Stern–Volmer plot for the quenching by complex 2 demonstrated preferential binding near one of the two tryptophan residues of BSA. The binding constants obtained (Kb) showed that BSA had a two orders of magnitude higher affinity for complex 2 than for 1. The results also showed that the affinity of both complexes for BSA was much higher than for DNA. This preferential interaction with protein sites could be important to their biological mechanisms of action. The analysis in vitro of the Zn(II) complexes and corresponding ligand were assayed against Trypanosoma cruzi, the causative agent of Chagas disease and the data showed that complex 2 was the most active against bloodstream trypomastigotes.
Keywords: Norfloxacin
Zn(II) complexes
Anti-T. cruzi activity
Acid ionization constant
Interaction with bovine serum albumin
Interaction with DNA
Trypanosoma cruzi
Chagas disease
DeCS: Norfloxacino
Trypanosoma cruzi
Doença de Chagas
Issue Date: 2013
Publisher: Springer
Citation: GOUVEA, Ligiane R.; et al. Norfloxacin Zn(II)-based complexes: acid base ionization constant determination, DNA and albumin binding properties and the biological effect against Trypanosoma cruzi. Biometals, v.26, n.5, p.813-825, Oct. 2013.
DOI: 10.1007/s10534-013-9661-z
ISSN: 1572-8773
Copyright: restricted access
Appears in Collections:IOC - Artigos de Periódicos

Files in This Item:
File Description SizeFormat 
marianazare_cordeiro_etal_IOC_2013.pdf629.44 kBAdobe PDF    Request a copy


FacebookTwitterDeliciousLinkedInGoogle BookmarksBibTex Format mendeley Endnote DiggMySpace

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.