Electroless‐coated magnetic three‐dimensional graphene with silver nanoparticles used for the determination of pesticides in fruit samples

Abstract

A new type of adsorbent composed of magnetic three-dimensional graphene coated with silver nanoparticles was synthesized by an electroless technique and used in the magnetic solid-phase extraction of selected pesticides (fenitrothion, chlorpyrifos, and hexaconazole) before gas chromatography with a micro-electron capture detector. The adsorbent was characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometry, and field-emission scanning electron microscopy. The important extraction parameters such as pH, adsorbent dose, extraction time, and desorption conditions were investigated. Under the optimal conditions, the analytical figures of merit were obtained as: linear dynamic range of 0.1-5 ng/g with determination coefficients of 0.991-0.996; limit of detection of 0.07-0.13 ng/g; limit of quantification of 0.242-0.448 ng/g; and the intraday and interday relative standard deviations (C = 5 ng/g, n = 3) were 3.8-8.7 and 6.6-8.9%, respectively. The developed method was successfully applied for analysis of the selected pesticides in tomato and grape with extraction recoveries in the range of 72.8-109.6%.

Dispersive clean‐up process based on a magnetic graphene oxide nanocomposite for determination of 2‐glycerol monopalmitate in olive oil prior to GC‐FID and GC‐MS analysis

“…The successful introduction of magnetic nanoparticles (MNPs) over the surface of GO could be noted from the thoroughly distributed nanoparticles. The almost uniform distribution of magnetic nanoparticles and the reticular porous structure demonstrate the three‐dimensional nature of MGO and contribute to the higher adsorption capacity and surface area of the reported material 23 …”

“…The almost uniform distribution of magnetic nanoparticles and the reticular porous structure demonstrate the three-dimensional nature of MGO and contribute to the higher adsorption capacity and surface area of the reported material. 23 Vibrating sample magnetometer (VSM) A VSM technique was used for the characterization of the magnetic properties of the magnetic MGO nanocomposite. The VSM graph is shown in Fig.…”

“…In accordance with previous studies, 22,23 magnetic graphene was prepared as follows: 0.14 g of GO and 1.4 g of FeSO 4 .7H 2 O were suspended in 70 mL of distilled water followed by ultrasonication for 30 min. Then, the pH of the suspension was adjusted to 11 with ammonia solution (25%).…”

An efficient 3D adsorbent foam based on graphene oxide/AgO nanoparticles for rapid vortex-assisted floating solid phase extraction of bisphenol A in canned food products

“…In the graphene oxide spectrum, the bands located at 1036, 1203, 1567, 1721, 2910, and 3420 cm À1 can be assigned to C-O epoxy, aromatic C]C and C-C, C]O, C-H, and O-H stretching vibrations, respectively for the surface functional groups of GO. 17 In the GO-Ag@Ni foam spectrum, all GO bands have appeared in the spectrum. Furthermore, the new absorption peaks at 810 cm À1 (Ag-O), 1021 cm À1 (C-O-Ag) and 1680 cm À1 (O]C-O-Ag) can be attributed to the presence of Ag NPs dispersed on the surface of graphene oxide.…”

Magnetic solid‐phase extraction of tobacco‐specific N‐nitrosamines using magnetic graphene composite as sorbent

“…Graphene is a two‐dimensional honeycomb lattice material composed of carbon atoms . Due to the large specific area, good thermal and chemical stability, and π‐π electrostatic stacking properties graphene‐based materials have a variety of applications in modern sample preparation techniques , and graphene‐based sorbents have been used for extraction of polycyclic aromatic hydrocarbons , pesticide residues , mycotoxins , antibiotic drugs , nicotine , phytohormones , heavy metals , aromatic amines , and siloxanes in various samples. And recent studies have illustrated that graphene‐based materials have high adsorption capacity for TSNAs .…”