Electrochemical characterization of melamine electropolymerized in deep eutectic solvents for selective detection of dopamine

• Main Authors: Chang, Yeet Hoong, Woi, Pei Meng, Alias, Yatimah
• Format: Article
• Published: Springer 2021
• Subjects: QD Chemistry
• Online Access: http://eprints.um.edu.my/27008/

We report here for the first time the polymerization of melamine in three different type III deep eutectic solvents (DESs), namely ethaline, glyceline and reline. The novel DESs functionalized polymelamine (PME-DESs) modified glassy carbon electrode was compared with conventional electrolytes including sulphuric acid and neutral Cl- aqueous solution. The key effect of the potential window, the acidity of the electrolyte, concentration of melamine and Cl- and the temperature of electrolyte on the polymerization of melamine have been further studied to choose the best PME-DESs. The selected PME(ethaline) was further incorporated with hydroxyl functionalized multi-walled carbon nanotube (f-WMCNTs) and applied in selective sensing of dopamine. PME(ethaline)/f-MWCNTs/GCE demonstrated excellent electrocatalytic activity towards dopamine oxidation. The observed linear range for the detection of dopamine concentration, without interferences through differential pulse voltammetry (DPV), was from 1.0 mu M to 1.0 mM (R-2 = 0.9924), with a detection limit of 288 nM (S/N = 3). Studies proved that the modified electrode can be successfully applied for the quantitative determination of dopamine both with and without interferences.