The electrochemical studies for chitosan hydrogel membranes on glassy carbon substrates

This dataset contains various electrochemical studies carried out to investigate the preconcentration of [Fe(CN)6]3- ions by chitosan hydrogel membranes coating the glassy carbon electrodes. 

The glassy carbon electrode (GCE, 3.0 mm diameter) was first polished with Al2O3 powder (0.3 mm) using a polishing kit from Buehler, rinsed with deionized water from Hydrolab Poland, and then dried under a continuous stream of nitrogen at room temperature. Then 5 μL of chitosan hydrogel was applied to the surface thus prepared using an automatic pipette and dried in a stream of nitrogen at room temperature for 30 min. The measuring system consisted of a self-designed vessel, the GCE and Ag/AgCl electrodes from Mineral, and the Pt wire came from Mennica Polska.
These measurements were taken using a Methron Autolab potentiostat/galvanostat, M204 equipped with FRA32M electrochemical impedance spectroscopy module with operating system Nova 2.15. The electrochemical studies of the prepared electrodes were evaluated in a three-electrode system, with a modified GCE as a working electrode, an Ag/AgCl (0.1 M KCl) reference electrode, and a platinum mesh as a counter electrode. The influence of surface engineering by hydrogel coating on the electrode kinetics was evaluated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Electrochemical studies were carried out with 1 mM K3[Fe(CN)6], [K4Fe(CN)6], C12H14FeO2, and [Ru(NH3)6]Cl2 dissolved in 0.1 M KCl or PBS as the primary electrolyte. Cyclic voltammograms were registered with scan rates between 10 and 1000 mV/s, and in the potential range −0.35 V to 0.65 V. DPV experimental conditions were: scan rate 10 mV/s, step potential 0.005 V, modulation amplitude 0.025 V, modulation time 0.05 s and interval time 0.5 s, polarization range from −0.3 V to 0.8 V.

These results are part of the manuscript: https://www.sciencedirect.com/science/article/pii/S156753942400166X