Dissolved Organic Matter-Capped Silver Nanoparticles for Electrochemical Aggregation Sensing of Atrazine in Aqueous Systems

Abstract

An electrochemical sensor based on silver nanoparticles (AgNPs) was developed by immobilizing dissolved organic matter (DOM) to interact with AgNPs on a glassy carbon electrode (GC), forming a DOM/AgNP/GC composite. AgNPs have been fabricated and characterized using ultraviolet–visible spectroscopy, fluorescence spectroscopy, and transmission electron microscopy. The immobilization efficiency and stability of the DOM/AgNP/GC composite have been optimized through studying the effects of electrode material type, immobilization technique, sticking duration, supporting electrolyte, and pH using square wave anodic stripping voltammetry. The detection of atrazine (Atz), a common herbicide, in aqueous systems has a great significance because of its toxicity to humans and other animals. The DOM/AgNP/GC composite has been used for Atz assessment under the optimized conditions based on the aggregated and nonaggregated AgNPs. The sensor linear range is between 20 and 220 μg/L for both aggregated and nonaggregated AgNP-based sensors. Atz could also be detected on the basis of its electrochemical oxidation at DOM/AgNP/GC with a linear range of 10–140 μg/L. Both sensors have been employed for the assessment of Atz in natural water with acceptable recovery values.

Individual and Simultaneous Voltammetric Determination of Ultra-Trace Environmental Contaminant Dihydroxybenzene Isomers Based on a Composite Electrode Sandwich-like Structure

“…The effective surface area of bare GCE, DAN/GCE, and PdDAN/GCE has been measured by applying the effect of the scan rate on the standard substance, 20 as shown in Figure 1 . The effect of the scan rate has provided a linear relation between the peak current ( I p ) values and the square root of the scan rate ( v 1/2 ) at PdDAN/GCE that indicates a diffusion-controlled electrode reaction, 20 , 21 as presented in Figure 2 c. The surface area ( A ) has been calculated from the regression analysis of the linear relation, as presented in Figure 2 b, and slope value of the linear line applied in a Randles-sevcik equation. 20 The surface area value has been calculated for bare GCE, DAN/GCE, and PdDAN/GCE to be 0.072, 0.113, and 0.561 cm 2 , respectively.…”

Recent advances in silver nanoparticle-based electrochemical sensors for determining organic pollutants in water: a review

“…The ex situ approaches include drop casting, spin coating, sticking, transfer sticking, and carbon paste modification. The drop casting technique depends on the placement of AgNPs directly on electrode surfaces with subsequent drying for solvent evaporation 110 (Figure 2B). In the spin coating technique (Figure 2C), AgNPs are directly placed on the surface of a stirring electrode attached to the center of the spin coater via a vacuum system 111 .…”

“…In the spin coating technique (Figure 2C), AgNPs are directly placed on the surface of a stirring electrode attached to the center of the spin coater via a vacuum system 111 . In the sticking technique (Figure 2D), the electrode is dipped in an AgNP suspension mixed with electrolytes for a certain time 110 . Similarly, the transfer sticking technique is accomplished by dipping the electrode in an AgNP suspension only, which is then transferred to the electrolyte for the stripping process (Figure 2E).…”

Mucilage-capped silver nanoparticles for glucose electrochemical sensing and fuel cell applications

“…Mucilage-AgNPs were deposited at the GC surface via the transfer-sticking technique. 14 The electrode was submerged in the nanoparticles stock suspension for 1 h for efficient adhesion.…”

“…12,13 Recently, we reported the synthesis of AgNPs through direct chemical reduction using dissolved organic matter and natural latex to constructing pioneering electrochemical sensors for pesticides and dye determination in aqueous systems. 14,15 AgNPs were used for glucose sensing via colorimetric techniques such as surface plasmon resonance (SPR), uorescence and surface enhanced Raman spectroscopy. [16][17][18] Concerning the electrochemical techniques, AgNPs were used for glucose sensing and glucose fuel cell applications based on glucose oxidation.…”