Electrochemical behaviour of isatin at a glassy carbon electrode.
The electrochemical behavior of isatin--a molecule with a broad range of applications in synthetic, biological and clinical activity--has been investigated over a wide pH range at a glassy carbon electrode (GCE) using cyclic, square wave and differential pulse voltammetry. The oxidation of isatin is an irreversible process, pH dependent and occurs with the formation of a main oxidation product that strongly adsorbs on the electrode surface. The reduction of isatin is also a pH dependent irreversible process. Cyclic voltammograms show two consecutive charge transfer reactions. The diffusion coefficient of isatin was calculated in pH 7.0 phosphate buffer to be D(0)=4.9 x 10(-7) cm2 s(-1). The limit of detection obtained in a solution of pH 7.0 phosphate buffer was LOD=0.194 microM, based on three times the noise level.
Diculescu
Victor C
VC
Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-535 Coimbra, Portugal.
Kumbhat
Sunita
S
Oliveira-Brett
Ana Maria
AM