Evidence of an EC' mechanism occurring during the simultaneous assay of ascorbic and uric acids on poly(3,4-ethylenedioxythiophene) modified gold microsensor.

Fadhila Sekli-Belaidi (1) , David Evrard (1) , Pierre Gros (1)

1 LGC - Laboratoire de Génie Chimique

A voltammetric microsensor has been developed for the simultaneous assay of ascorbic (AA) and uric (UA) acids in aq. soln. The electrode surface has been modified by means of electropolymd. conductive poly(3,4-ethylenedioxythiophene) (PEDOT) org. films. The anodic peak potential sepn. between both acids was more than 300 mV. The sensitivity of the microsensor for UA was found to be dependent on the presence of AA in the mixt. By using square wave voltammetry (SWV), it increased from 77.5 mA mM-1 cm-2 without AA to 86.2 mA mM-1 cm-2 with AA 1 mM. An EC' catalytic mechanism was highlighted, inducing the regeneration of reduced UA by AA at the vicinity of the electrode surface.

Mots clés: Electrochemical microsensor; PEDOT film; Ascorbic and uric acids assay; EC' mechanism

Domaines: Génie chimique

Fadhila Sekli-Belaidi, David Evrard, Pierre Gros. Evidence of an EC' mechanism occurring during the simultaneous assay of ascorbic and uric acids on poly(3,4-ethylenedioxythiophene) modified gold microsensor.. Electrochemistry Communications, 2011, 13, pp.423-425. ⟨10.1016/j.elecom.2011.02.009⟩. ⟨hal-03544432⟩