Accurate and Rapid Determination of Ammonium in Water by Voltametric Analysis on a Novel Modified Electrode

Abstract

The development of efficient and sensitive electrochemical sensors is of crucial for a wide range of applications, including environmental monitoring, chemical analysis, and biomedical diagnostics. In this study, we present on the development and characterization of a novel of electrochemical sensor, based on a silver/poly 1-aminoanthraquinone/glassy carbon modified electrode (Ag/PAAQ/GC), with high sensitivity and selectivity for the detection of ammonium ions (NH4 +) in water. The Ag/PAAQ/GC electrode was prepared by a simple and low- cost electrochemical co-deposition method, which enabled for a uniform and stable deposition of PAAQ and Ag ions on the surface of the GC electrode. The resulting electrode exhibited excellent electrocatalytic activity in the oxidation of NH4 + ions. The performance of the Ag/PAAQ/GC electrode as an electrochemical sensor for NH4 + was evaluated using square wave voltammetry (SWV) in aqueous solutions. The results showed that the Ag/PAAQ/GC electrode exhibited a linear response to NH4 + in a concentration range of 0.01 to 9 mgL−1, with a detection limit of 3 μgL−1 and a sensitivity of 0.0413 μA.Lmg−1. In addition, the Ag/PAAQ/GC electrode showed excellent selectivity for NH4 + over interfering ions such as K+, Na+, Ca2+, and Mg2+. Overall, our results show that the Ag/PAAQ/GC electrode is a promising platform for the development of advanced electrochemical sensors for the detection of NH4 + in water. Due to its high sensitivity, selectivity and stability, the Ag/PAAQ/GC electrode is suitable for a wide range of environmental and analytical applications, e.g., water quality monitoring, wastewater treatment and fertiliser analysis. The precision of the method was tested by analysing sixteen measurements of the same NH4 + concentration, yielding standard deviation (RSD) of 1.78%. Good recovery values were obtained when measuring spiked tap water samples analysed by the classical Colorimetric Nessler reagent methods and measuring natural water by the ion-selective electrode.