Title:Simultaneous Electrochemical Evaluation of Ascorbic Acid, Epinephrine and Uric Acid at Disposable Pencil Graphite Electrode: Highly Sensitive Determination in Pharmaceuticals and Biological Liquids by Differential Pulse Voltammetry
Volume: 21
Issue: 7
Author(s): Abdulkadir Levent*Günay Önal
Affiliation:
- Department of Analytical Chemistry, Faculty of Science and Art, Batman University, Batman 72100,Turkey
Keywords:
Pencil graphite electrode, ascorbic acid, epinephrine, uric acid, simultaneous, biological liquids.
Abstract: Aim and Objective: As is known, AA, EP and UA can also coexist in biological fluids.
Therefore, the determination of the levels of these compounds in biological fluids is extremely
important both for the diagnosis and treatment of the related diseases. In the presence of many
interfering substances in biological fluids such as blood and urine samples, it is very important that
these compounds can be selectively analyzed.
Materials and Methods: All electrochemical experiments were performed using an Autolab
PGSTAT 128N potentiostat. Before beginning the electrochemical measurements, the PGE was
activated. The electrochemical pretreatment of PG was exercised by anodically +1.40 V for 60 s.
Then, measurements were performed with CV (-0.4 V to 1.2 V) and DPV (-0.2 V to 0.7 V) for single
and simultaneous voltammetric behaviour of AA, EP, and UA in the electrochemical method.
Results: The anodic peak potentials of AA and UA were observed at about +0.32 V and +0.62 V,
respectively. On the other hand, for EP, while anodic peak potential was observed at about +0.53 V,
in the reverse scan, cathodic peak potentials were observed at about +0.41 V and +0.007 V. The
reduction peak observed at +0.3 V with the oxidation peak observed at +0.53 V are the reversible
peaks. In the method developed for the electrochemical simultaneous determination of AA, EP and
UA using PGE with DPV technique in BR buffer solution (pH 4.0), the anodic peak potentials are
sufficiently separated from each other.
Conclusion: A voltammetric method was developed for the simultaneous determination of AA, EP
and UA with PGE for the first time. Here, the most important thing is that the simultaneous
determination of AA, EP and UA was successfully achieved with that targeted voltammetric method
which was sensitive, low-cost, practical and well-repeated; and that these were proven to be
selectively applicable in pharmaceutical products and biological liquids.
