Magnetic Solid-Phase Extraction of Carbamate Pesticides Using Magnetic Metal–Organic Frameworks Derived from Benzoate Ligands, Followed by Digital Image Colorimetric Screening and High-Performance Liquid Chromatography Analysis

Abstract

Magnetic sorbents based on iron–aluminum-mixed metal hydroxides composited with metal–organic frameworks (MOFs) were designed and synthesized using different benzoate ligands, including terephthalic acid, 2-aminoterephthalic acid, 2,5-dihydroxyterephthalic acid, 1,3,5-benzenetricarboxylic acid, and 1,2,4,5-benzenetetracarboxylic acid. The magnetic MOF derived from terephthalic acid ligand exhibited an excellent extraction efficiency, with adsorption capacities in the range of 2193–4196 mg kg –1 , and was applied for magnetic solid-phase extraction (MSPE) of carbamate pesticides, that is, bendiocarb, carbosulfan, carbofuran, carbaryl, propoxur, isoprocarb, and promecarb. Simple digital image colorimetry based on the diazotization reaction and high-performance liquid chromatography (HPLC) were utilized for fast screening and quantification purposes, respectively. A good analytical performance for a simple screening approach using portable equipment was obtained with detection limits in the range of 1.0–18.0 μg L –1 . Under the optimized MSPE-HPLC conditions, the entire developed procedure provided a wide linear range between 0.015 and 1000 μg L –1 , low limits of detection, and limits of quantitation ranging from 0.005 to 0.090 and 0.015–0.300 μg L –1 , respectively. Enrichment factors up to 184 were achieved. The intra- and interday relative standard deviations were below 6.7 and 9.4%, respectively. The proposed MSPE-digital image colorimetry and MSPE-HPLC methods were successfully applied for screening and determining carbamate pesticides in fruits and vegetables. The recoveries were obtained in a satisfactory range of 71.5–122.8%. This discovery has led to the development of integration methods using newly synthesized sorbent materials for the enrichment of carbamate pesticides prior to their analysis in complicated samples. The developed MSPE coupled with digital image colorimetry was efficient for fast carbamate contamination screening, while MSPE-HPLC offered a sensitive analytical methodology for quantifying contaminated samples.

Modified Peanut Shell as an Eco-Friendly Biosorbent for Effective Extraction of Triazole Fungicide Residues in Surface Water and Honey Samples before Their Determination by High-Performance Liquid Chromatography

“…Acetonitrile has high solvent eluotropic strength, which makes it suitable for interrupting between analyte and sorbent interactions. 36 Moreover, the volume of desorption solvent (acetonitrile) was examined in the range of 100–300 μL. The extraction efficiency gradually increased with an increasing desorption solvent volume from 100 to 200 μL and then remained almost constant afterward (as shown in Figure 4 e).…”

“…When acetonitrile was used as a desorption solvent (data not shown), good extraction efficiency was obtained. Acetonitrile has high solvent eluotropic strength, which makes it suitable for interrupting between analyte and sorbent interactions . Moreover, the volume of desorption solvent (acetonitrile) was examined in the range of 100–300 μL.…”

Metal-porphyrinic framework nanotechnologies in modern agricultural management

“…The interest in magnetic MOFs resides in the possibility of performing solid-phase extraction allowing for the analysis of the species such as pesticides 92,93 and metal ions. 94 Magnetic composites of metal-porphyrinic MOFs are also known and mainly involve Fe 3 O 4 nanoparticles as the magnetic component in composites (for instance Fe 3 O 4 @SiO 2 @PCN-222(Fe)).…”

Deep eutectic solvent-based dispersive liquid–liquid microextraction followed by smartphone digital image colorimetry for the determination of carbofuran in water samples

“…Various methods for detecting CBF residues in the environment have been applied such as high-performance liquid chromatography, 21 gas chromatography-mass spectrometry, 22 enzyme-linked immunosorbent assay, 23 and electrochemical methods. 24,25 Although these methods meet the requirements of detection in terms of specificity, sensitivity, and accuracy, they need expensive equipment, time-consuming processing, and skilled operators; therefore, there is a need for developing a simple CBF detection method in water samples.…”