Effect of cyclodextrrins on the electrochemical behaviour of ascorbic acid on golg electrodes

M.I.MANZANARES CUELLO, V.M.SOLIS AND R.H.DE ROSSI

JOURNAL OF ELECTROANALYTICAL CHEMISTRY

ELSEVIER

Lugar: Amsterdam; Año: 1996 vol. 407 p. 141 - 141

0022-0728

he study of the inclusion complexes formed by ascorbic acid with fl-cyclodextrin at different pH is reported. Special attention is paidto the electrochemical behaviour of ascorbic acid in the presence of the macrocycle on gold electrodes. The modifications observed can beexplained by the decrease in the diffusion coefficient of the complex and the presence of an additional chemical step, the dissociation ofthe complex prior to the electron transfer steps. The inclusion of ascorbic acid in fl-cyclodextrin increases the stability of the guestmolecule to oxidising agents. Adsorption of /3-cyclodextrin on gold is also detected, depending on the pH. No effect of ascorbic acidbehaviour owing to the addition of a-cyclodextrin was observed.