Amperometric Determination of Folic Acid at Multi-Walled Carbon Nanotube-Polyvinyl Sulfonic Acid Composite Film Modified Glassy Carbon Electrode

摘要

We investigated the electrochemical reduction behavior of folic acid (FA) at multi-walled carbonnanotube-polyvinylsulfonate (MWCNT-PVS) composite film modified glassy carbon electrode (GCE)+ using cyclic voltammetry (CV). FA undergoes a 2e /2H transfer electrochemical reduction process at.7 V with respect to Ag/AgCl reference electrode in pH 7. The reduction peak current increasedlinearly with the increase in concentration of FA. So far no reports are available for the amperometricdetermination of FA utilizing the reduction process occurring at negative over potential (0.7 V). Weattempted the amperometric studies making use of this reduction process at .7 V. MWCNT-PVS-5modified electrode showed good amperometric response in the wide linear range from 5.3 x 10 M to-3 1.7 x 10 M with a sensitivity of 0.1737 A mol cm . The surface morphology of MWCNT-PVSfilm was done by scanning electron microscopy (SEM) and the interfacial electron transferphenomenon at the modified electrode surface was studied using electrochemical impedancespectroscopy (EIS). The studies showed that MWCNT is well dispersed in PVS and the composite filmpossesses less electron transfer resistance making it a promising material for electrocatalytic andbiosensing applications.