ABSTRACT
An electrochemical sensor based on nickel tetraamine phthalocyanine and nitrogen doped grapheme oxide (NITAPC-NDGONS (mix)) nanoparticles was developed for the simultaneous electrocatalytic oxidation of vanillin and ascorbic acid. FTIR (Fourier Transimition Infrared), electrochemical impedance spectroscopy (EIS) and Bode plots were used in the characterization of the synthesized modifiers (NITAPC), (GONS-NITAPC) and NITAPC-NDGONS (mix)). Cyclic voltammetry, linear sweep, chronoamperometry and differential pulse voltammetry were used to assess the electrocatalytic efficiency towards oxidation of vanillin and ascorbic acid. The surface area of the modified electrode was 0.173 cm2 and the surface coverage was 7.60 x 10-13 mol cm2. The catalytic rate constant of ascorbic acid was 1.59 x 108 M-1 s-1 and for vanillin it was 1.28 x 108 M-1 S-1 . The apparent electron transfer rate constant was 2.05 x 10-2 cm s-1 .The adsorption equilibrium constant for ascorbic acid was 6.4 x 102 M-1 and for vanillin was 8.05 x 102 M-1 . Gibbs free energy for ascorbic acid was -16.01 kJ and for vanillin was -16.57 kJ. The limit of detection was 8.6 x 10-8 M and the limit of quantification was 2.6 x 10-7 M for ascorbic acid and Limit of detection (LOD) was 2.58 x10-8 M and Limit of quantification (LOQ) was 6.8 x 10-8 M for vanillin. Interference studies were done and the electrode displayed the ability to detect both vanillin and ascorbic acid in the presence of citric acid. The electrode displayed good reproducibility.
TAKUDZWA, M (2021). SIMULTANEOUS DETECTION OF VANILIN AND ASCORBIC ACID ON A PLATFORM MODIFIED WITH NICKEL TETRAAMINE PTHALOCYANINE NITROGEN DOPED GRAPHENE.. Afribary. Retrieved from https://afribary.com/works/simultaneous-detection-of-vanilin-and-ascorbic-acid-on-a-platform-modified-with-nickel-tetraamine-pthalocyanine-nitrogen-doped-graphene
TAKUDZWA, MARINGO "SIMULTANEOUS DETECTION OF VANILIN AND ASCORBIC ACID ON A PLATFORM MODIFIED WITH NICKEL TETRAAMINE PTHALOCYANINE NITROGEN DOPED GRAPHENE." Afribary. Afribary, 04 May. 2021, https://afribary.com/works/simultaneous-detection-of-vanilin-and-ascorbic-acid-on-a-platform-modified-with-nickel-tetraamine-pthalocyanine-nitrogen-doped-graphene. Accessed 21 Nov. 2024.
TAKUDZWA, MARINGO . "SIMULTANEOUS DETECTION OF VANILIN AND ASCORBIC ACID ON A PLATFORM MODIFIED WITH NICKEL TETRAAMINE PTHALOCYANINE NITROGEN DOPED GRAPHENE.". Afribary, Afribary, 04 May. 2021. Web. 21 Nov. 2024. < https://afribary.com/works/simultaneous-detection-of-vanilin-and-ascorbic-acid-on-a-platform-modified-with-nickel-tetraamine-pthalocyanine-nitrogen-doped-graphene >.
TAKUDZWA, MARINGO . "SIMULTANEOUS DETECTION OF VANILIN AND ASCORBIC ACID ON A PLATFORM MODIFIED WITH NICKEL TETRAAMINE PTHALOCYANINE NITROGEN DOPED GRAPHENE." Afribary (2021). Accessed November 21, 2024. https://afribary.com/works/simultaneous-detection-of-vanilin-and-ascorbic-acid-on-a-platform-modified-with-nickel-tetraamine-pthalocyanine-nitrogen-doped-graphene