Simultaneous determination of pindolol, acebutolol and metoprolol in waters by differential-pulse voltammetry using an efficient sensor based on carbon paste electrode modified with amino-functionalized mesostructured silica

Publication date: 15 March 2019Source: Sensors and Actuators B: Chemical, Volume 283Author(s): Mariana Silva, Sonia Morante-Zarcero, Damián Pérez-Quintanilla, Isabel SierraAbstractIn this work, hexagonal mesoporous silica (HMS) and amino-functionalized HMS (HMS-NH2) were prepared and incorporated into carbon paste electrodes (CPEs) to obtain electrochemical sensors for pindolol (Pin), acebutolol (Ace) and metoprolol (Met) determination in waters by voltammetric techniques. The materials were characterized and they showed high specific surface area, large pore volume and a quasi-spherical morphology. Firstly, the electrochemical behaviour of the modified CPEs was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Then, the dependence of the current intensity with the electrolyte support (type and pH) and the accumulation time was investigated to optimize the experimental conditions for simultaneous β-blockers determination by DPV. Results showed that the sensor modified with functionalized silica (NH2-HMS-CPE) exhibited strong adsorption activity, showing three well-defined peaks in the differential pulse voltammograms, that appeared at about +0.85 V (Pin), +1.11 V (Ace) and +1.45 V (Met). This fact can be attributed to the high surface area of the material, with a 3 D wormhole-like channel structure that favoured excellent pore accessibility, and the synergistic effect produced by the grafted amino groups producing hydrogen bond interactions...

Source: Sensors and Actuators B: Chemical - December 18, 2018 Category: Chemistry Source Type: research