Voltammetric determination of L-dopa using an electrode modified with trinuclear ruthenium ammine complex (Ru-red) supported on Y-type zeolite


Autoria(s): Teixeira, MFS; Bergamini, M. E.; Marques, CMP; Bocchi, N.
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

08/07/2004

Resumo

The L-dopa is the immediate precursor of the neurotransmitter dopamine. Unlike dopamine, L-dopa easily enters the central nervous system and is used in the treatment of Parkinson's disease. A sensitive and selective method is presented for the voltammetric determination of L-dopa in pharmaceutical formulations using a carbon paste electrode modified with trinuclear ruthenium ammine complex [(NH3)(5)Ru-III-O-Ru-IV(NH3)(4)-O-Ru-III(NH3)(5)](6+) (Ru-red) incorporated in NaY zeolite. The parameters which influence on the electrode response (paste composition, potential scan rate, pH and interference) were also investigated. The optimum conditions were found to an electrode composition (m/m) of 25% zeolite containing 6.7% Ru, 50% graphite and 25% mineral oil in acetate buffer at pH 4.8. Voltammetric peak currents showed a linear response for L-dopa concentration in the range between 1.2 x 10(-4) and 1.0 x 10(-2) Mol l(-1) (r = 0.9988) with a detection limit of 8.5 x 10(-5) mol l(-1). The variation coefficient for a 1.0 x 10(-3) mol l(-1) L-dopa (n = 10) was 5.5%. The results obtained for L-dopa in pharmaceutical formulations (tablet) was in agreement with compared official method. In conclusion, this study has illustrated that the proposed electrode modified with Ru-red incorporated zeolite is suitable valuable for selective measurements of L-dopa. (C) 2004 Elsevier B.V. All rights reserved.

Formato

1083-1088

Identificador

http://dx.doi.org/10.1016/j.talanta.2004.01.018

Talanta. Amsterdam: Elsevier B.V., v. 63, n. 4, p. 1083-1088, 2004.

0039-9140

http://hdl.handle.net/11449/249

10.1016/j.talanta.2004.01.018

WOS:000222063600034

Idioma(s)

eng

Publicador

Elsevier B.V.

Relação

Talanta

Direitos

closedAccess

Palavras-Chave #modified carbon paste #Ru-red/zeolite Y #voltammetric determination #L-dopa #pharmaceutical formulations
Tipo

info:eu-repo/semantics/article