Development of Hydroquinone Amperometric sensor using a modified paste electrode based on ionic liquid 1-Ethtl-3-Methylimidazolium Bromide

This study aims to develop a graphene composite modified paste electrode (GrPE) based on ionic liquid 1-ethyl-3-methylimidazolium bromide (EMIMBr) to detect hydroquinone. The electrochemical properties of the modified electrode were determined using square wave voltammetry and electrochemical impedance spectroscopy. The results showed that under optimal conditions, the modified electrode showed a linear concentration range of 1.0×10-6 to 1.0×10-2 M with a detection limit of hydroquinone, 2.77×10-7 M. The interferences from Ba2+, Cu2+, Na+, K+, NO3-, Cl-, SO4 2-, glycine, glucose, fructose and sucrose were negligible. Electrochemical impedance spectroscopy indicated that the charge transfer at the electrode-solution interface was excellent. The proposed electrode was successfully applied to determine hydroquinone in wastewater samples and cosmetic creams with range of recovery 97 – 104%. In conclusion, the modified electrode that has been developed is able to detect hydroquinone. Therefore, the modified electrode is a suitable alternative for the determination of hydroquinone due to its sensitivity, selectivity and high reproducibility.