Sparked ZnO nanoparticles-based electrochemical sensor for onsite determination of glyphosate residues

Abstract

Glyphosate (N-(phosphonomethyl)glycine) is well known nonselective and broad-spectrum herbicide that has been extensively used in agricultural areas around the world to increase agricultural productivity. However, the utilization of glyphosate can cause environmental contamination and health problems. Therefore, the detection of glyphosate with a fast, low-cost, and portable sensor is still important. In this work, the electrochemical sensor has been developed by modifying of working surface on the screen-printed silver electrode (SPAgE) with a mixtures solution between zinc oxide nanoparticles (ZnO-NPs) and poly (diallyldimethylammonium chloride) (PDDA) by the drop-casting process. The ZnO-NPs have been prepared based on a sparking method by using pure zinc wires. The ZnO-NPs/PDDA/SPAgE sensor shows a wide range of glyphosate detection (0 µM - 5 mM). The limit of detection of ZnO-NPs/PDDA/SPAgE is 2.84 µM. The ZnO-NPs/PDDA/SPAgE sensor exhibits high selective towards glyphosate with minimal interference from other commonly used herbicides including paraquat, butachlor-propanil and glufosinate-ammonium. Furthermore, the ZnO-NPs/PDDA/SPAgE sensor demonstrates a good estimation of glyphosate concentration in real samples such as green tea, corn juice and mango juice.

An Optimized MnO2-Ag Nanocomposite-Based Sensing Platform for Determination of 4-nitrophenol in Tomato Samples: Influences of Morphological Aspect of MnO2 Nanostructures and Synergic Effect on Electrochemical Kinetic Parameters and Analytical Performance

“…This approach has not only been widely mentioned and attracted at bare screen-printed electrodes (SPEs) in particular and other commercial electrodes, in general. A series of materials have been investigated and evaluated such as metal/metal oxides (Au, 1 Ag, 2 ZnO, 3,4 Cu x O, 5 Fe x O y , 6 MoS 2 , 7 MnO 2 , [8] etc); carbonaceous materials (graphene, graphene oxides (GO), 9 carbon nanotubes, and carbon dots); conducting polymers; 10 ); metal-organic frameworks (MOFs); 13 even their composite structures (Au@Graphene, 14 MoS 2 @GO, 15,16 Ag-Fe 3 O 4 , 17 MnO 2 -graphene 18,19 ). Not an exception to that trend, both MnO 2 nanomaterials and Ag nanoparticles (AgNPs) have been used to modify electrode surfaces thanks to their unique features (low cost, high activity, nontoxicity, high electronic conductivity, biocompatibility, easy preparation, and tunable electrochemical redox chemistry).…”

Flexible and Stretchable Pressure Sensors: From Basic Principles to State-of-the-Art Applications

“…Flexible and stretchable pressure sensors utilizing resistive sensing typically consist of a conductive material embedded in a flexible matrix. The conductive materials can be carbon nanotubes (CNTs) [ 15 ], graphene [ 16 , 17 ], conductive polymers [ 18 ], ZnO nanoparticles [ 19 ], silver oxide nanoparticles [ 20 ] or lead oxide nanoparticles [ 21 ] with suitable electrical properties. When pressure is applied to the sensor, the conductive elements deform to alter the electrical resistance/conductivity.…”