Voltammetric Determination of Venlafaxine by Using Multiwalled Carbon Nanotube- Ionic Liquid Composite Electrode

The combination of multi-walled carbon nanotubes and ionic liquid 1-octylpyridinium hexaflourophosphate (OPFP) yields a carbon nanocomposite (MWCNT-CILE) that can be well used aselectrode for electrocatalytic oxidation of venlafaxine (VEN). The influence of variousexperimental parameters including pH of the solution, the amount of multi-walled carbon nanotubeused for the modification of the carbon ionic liquid electrode (CILE), accumulation potential,accumulation time and scan rate on the voltammetric responses of venlafaxine were all investigatedin the present research. The oxidation peak potential of venlafaxine appeared at 640 mV at theproposed electrode that is about 150 mV lower than the peak potential at traditional carbon pasteelectrodes (CPE). The oxidation is irreversible and exhibits adsorption controlled behavior. Underthe optimum conditions, the anodic peak current has a linear relationship with venlafexineconcentration in the range of 10.0 to 500.0μM. The detection limit (three times signal-to-noiseratio) of 0.47μM was found. Finally, the proposed sensor has the features of being sensitive,reproducible, easily renewable and cost effective which might suggest promising applications fordetermination of VEN in pharmaceiutical formualations as well as blood serum and urine samples.