A Sensitive and Selective Electrochemical Investigation of Dopamine at Fabricated Sorbitol Film Modified Pencil Graphite Electrode: A Voltammetric Study

The sorbitol film coated pencil graphite electrode was developed for the determination of Dopamine (DA) by using cyclic voltammetric method. Compared to bare pencil graphite electrode (BPGE) the poly (sorbitol) modified pencil graphite electrode (MPGE) exhibited a high sensitivity and better electrocatalytic performance towards the oxidation of DA in phosphate buffer solution (PBS) of pH 7.4. A well-defined redox peaks were observed with good enhancement signals at poly (sorbitol) MPGE. From the study of scan rate variation the electrode process was found to be diffusion controlled. A complete investigation of electrochemical parameters such as the heterogeneous rate constant (ks), and detection limit were measured for DA at poly (sorbitol) MPGE. The pH studies confirm that an equal number of protons and electrons were involved in the electrochemical detection of DA. The simultaneous determination of DA and Uric acid (UA) in their sample mixture was analysed by using cyclic voltammetric and differential pulse voltammetric techniques.