Abstract: Using the electrostatic self-assembly technique, the multilayer films containing multiwalled carbon nanotubes and ferrocene branched chitosan(MWCNTs@CHIT-Fc) and PSS were alternately fabricated on GCE modified with PDDA. The obtained thin films were characterized by CV, UV-Vis and SEM. The electrocatalytic oxidation of AA on the multilayer film electrode was studied in detail by CV. When the number of bilayers of MWCNTs@CHIT-Fc on the GCE is 6, the oxidation peak potential of AA was lowered by at least 0.4 V compared with that obtained at bare GCE. The current response of AA at different bilayers of MWCNTs@CHIT-Fc on the modified electrode was studied by amperometric method. The analytical performance of the modified electrode such as sensitivity, detection limit and linear range for AA determination can be turned to the desired level by adjusting the number of deposited MWCNTs@CHIT-Fc bilayers.

Key words: Multiwalled carbon nanotube, Ferrocene-branched chitosan, Multilayer film electrode, Ascorbic acid, Electrocatalysis