Determination of vitamin B6 (pyridoxine) in pharmaceutical preparations by cyclic voltammetry at a copper(II) hexacyanoferrate(III) modified carbon paste electrode

Author(s)

Marcos F. S. Teixeira ^[1] ; Aline Segnini ^[2] ; Fernando C. Moraes ^[3] ; Luiz H. Marcolino-Júnior ^[4] ; Orlando Fatibello-Filho ^[5] ; Éder T. G. Cavalheiro ^[6]

Affiliation

^[1] Universidade de São Paulo. Instituto de Química de São Carlos - Brasil

^[2] Universidade de São Paulo. Instituto de Química de São Carlos - Brasil

^[3] Universidade Federal de São Carlos. Departamento de Química - Brasil

^[4] Universidade Federal de São Carlos. Departamento de Química - Brasil

^[5] Universidade Federal de São Carlos. Departamento de Química - Brasil

^[6] Universidade de São Paulo. Instituto de Química de São Carlos - Brasil

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 14, n. 2, p. 316-321, 2003-04-00.

Abstract

A copper(II) hexacyanoferrate(III) (CuHCF) modified carbon paste electrode was used for the electroanalytical determination of pyridoxine (vitamin B6) in pharmaceutical preparations, using cyclic voltammetry. Diverse parameters were investigated for the optimization of the sensor response, such as composition of the electrode, electrolytic solution, effect of pH, scan rate of potential and interferences. The optimum conditions were found at an electrode composition of 20% CuHCF, 55% graphite and 25% mineral oil (m/m) in an acetate buffer (pH 5.5) containing 0.05 mol L-1 of NaCl. The range of determination of pyridoxine was from 1.2 x 10-6 to 6.9 x 10-4 mol L-1. The procedure was successfully applied to the determination of vitamin B6 in formulation preparations. The CuHCF modified carbon paste electrode gave results comparable to those obtained using spectrophotometry. (AU)