Electropolymerization of brilliant cresyl blue on carbon ionic liquid electrode and electrocatalytic application for the voltammetric determination of ascorbic acid

Brilliant cresyl blue (BCB) was electropolymerized on the surface of a carbon ionic liquid electrode (CILE) by cyclic voltammetric sweep in the potential range from -0.5 to 1.0 V. CILE was prepared by using 1-ethyl-3-methyl- imidazolium tetrafluoroborate ([EMIM]BF4) as modifier. The stable polymer film of BCB was obtained on the CILE and a pair of redox peaks appeared. The characteristics of PBCB film was studied by different methods such as scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. This modified electrode showed excellent electrocatalytic response to ascorbic acid with the increase of the electrochemical responses. Under the optimal conditions a good linear voltammetric response could be obtained over the range of 2.0x10-5-3.0x10-3 mol L-1 and the detection limit was got as 6.5 µmol L-1 (3σ).