Standardization of voltametric methods to measure the concentration of GSH and protein cysteine residues in erytrocytes and plasma

• Grant number: 10/02791-7
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2010
• End date: July 31, 2013
• Field of knowledge: Biological Sciences - Biochemistry
• Principal Investigator: Armindo Antonio Alves
• Grantee: Armindo Antonio Alves
• Host Institution: Pró-Reitoria de Pós-Graduação e Pesquisa. Centro Universitário Hermínio Ometto (UNIARARAS). Fundação Hermínio Ometto (FHO). Araras , SP, Brazil

Abstract

This work aims to standardize two voltammetric methods to measure the concentration of reduced sulfhydryl groups in both the reduced glutathione and cysteine residues of proteins and it relationship to the antioxidant capacity of biological fluids. This work intends to propose improvements in the search for efficient methods to evaluate changes in antioxidant capacity of biological fluids in order to use to diagnostic and monitoring diseases or physiological processes in which oxidative stress is a relevant factor. The voltametric methods are very interesting because of their fast response and saving of sample and reagents. In the first experiment will be used as working electrode the mercury drop electrode, the electrode Ag/AgCl / KCl 3 mol.L-1 as reference and a platinum wire as the counter-electrode. In the second method the working electrode is a bismuth film electrode. These working electrodes were chosen to permit the scanning of negative potential (-1 to 0 V). As samples, will be used biomolecular solutions with an increasing complexity. In first will be used as sample, reduced glutathione solutions (1 to 10.10-6 mol.L-1) and bovine serum albumin (1 to 40 mg / mL), without additions and with the addition of oxidants. Then will be used human red blood cells untreated and previously submitted to the oxidizing agent diamide. Finally human plasma will be used. Dosages of total sulfhydryl groups, TBARS and FRAP will be the control experiments. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TESSUTTI, L. S.; MACEDO, D. V.; KUBOTA, L. T.; ALVES, A. A.. Measuring the antioxidant capacity of blood plasma using potentiometry. Analytical Biochemistry, v. 441, n. 2, p. 109-114, OCT 15 2013. (10/02791-7)

MARIANO VILHENA, MARIA INES; CORREA-DA-SILVA, MARCOS VERGILIO; DE ARRUDA, ANA CAROLINA; RIBEIRO, BEATRIZ FELICIO; ZENI BERETTA, ANA LAURA REMEDIO; ALVES, ARMINDO ANTONIO. Measuring the Antioxidant Capacity Induced by Reduced Thiols in Human Erythrocytes Using SW-Voltammetry. International Journal of Electrochemical Science, v. 11, n. 8, p. 6453-6465, AUG 2016. (10/02791-7)