Selective Solid-Phase Extraction Using Molecularly Imprinted Polymer for Analysis of Methamidophos in Water and Soil Samples

Upadhyay

Arabian Journal of Chemistry

et al. 2015

Acephate and its metabolite methamidophos are common organophosphorus insecticide used for crop protection. High uses of acephate and methamidophos have induced health issues and environmental pollution. Their undesired presence in the environment is creating ecotoxicology and may harm human health. It is therefore essential to detect the presence of acephate and methamidophos even in trace level. In this review, we have tried to accommodate successful methods of detection of acephate and methamidophos in the different biological media. Their recovery and residue analysis in different media such as vegetables, human and animal tissues have also included. The most common method for their determination is based on chromatographic separation and identification. Among different chromatographic methods, LC and GC coupled with different detectors have used. But, they both need extensive pretreatment and cleanup procedure, before undergoing chromatographic separation and identification. LC coupled with mass spectrometry (LCMS) is sometime able to detect acephate and methamidophos in ppm level. ª 2015 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Section: Determination Of Acephate and Methamidophos In Soils And Watersmentioning

confidence: 94%

A review on sample preparation and chromatographic determination of acephate and methamidophos in different samples

Upadhyay

Arabian Journal of Chemistry

et al. 2015

“…As mentioned by some authors, the selection of the monomer(s) and the template/monomer(s) ratio can be carried out by studying the changes in UV spectra of the template when adding increasing concentration of the monomer in the solvent selected for the synthesis [67,69,77]. Other spectroscopic methods were used such as NMR to highlight the presence of hydrogen bonds between the template and MAA [39,67,69,72,73] and FT-IR to highlight the interactions between OPP and OH-group of MAA [39,46,55,61,70,76,80,91,97,98,102]. This method was also used to control the template removal by comparing MIP spectrum before and after its washing [64,93,99], this control being most of the time ensured by analyzing the template amount in the washing solution by UV detection or by chromatographic analysis.…”

Section: Synthesis Of Mipsmentioning

confidence: 99%

“…In these cases, the solvent used is very close or similar to the solvent used for the synthesis of the polymers to favor the same interactions as those developed during the polymerization step to create the cavities. The adsorption isotherm resulting from these binding experiments also allows, by using different models (Langmuir, Freundlich, Langmuir-Freundlich), the number of binding sites and their affinity towards the template molecules [80,93] and, in some cases, towards structural analogs to being defined [55,60,64,69,70,76,79,82,86,90,99]. Binding experiments were also carried out in a pure solvent, very similar to the nature of the sample matrix, such as aqueous buffer or pure water or acetonitrile for the further analysis of OPPs in aqueous or acetonitrile vegetable extracts, respectively [50,51,76,80,93,99].…”

Section: Mip Characterizationmentioning

confidence: 99%

Molecularly imprinted polymers for the determination of organophosphorus pesticides in complex samples

Boulanouar

Mezzache

Combès

et al. 2018

Talanta

123

Organophosphorus compounds constitute an important class of pesticides whose the toxicity of which arises from the inhibition of the acetylcholinesterase enzyme. They exhibit a wide range of physico-chemical properties, thus rendering their determination in complex oil samples particularly difficult. To facilitate their analysis at the trace level in various samples (environmental waters, soils, vegetables…), molecularly imprinted polymers (MIPs) that are synthetic polymers possessing specific cavities designed for a target molecule have been prepared. Often called synthetic antibodies, MIPs can replace antibodies in different application fields. Indeed, as immunosorbents, MIPs can be used as selective sorbents for the solid phase extraction of target analytes from complex matrices or as recognition elements in sensors. Their synthesis, characterization and use as selective sorbent for the selective recognition of organophosphorus pesticides have been already largely described and are summarized in this review.

Journal of Chromatography A

“…The development of MIPs for the extraction of OPs has been largely reported these last years. MIPs were prepared as particles to be used in cartridges between two frits as SPE sorbent [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] or as dispersive sorbent for dSPE [27][28][29][30][31] and for matrix solid-phase dispersion (MSPD) [32][33][34] or as a thin film in solid-phase microextraction (SPME) [35][36][37] or in stir bar sorption extraction (SBSE) [38]. They were applied to the selective extraction of OPs from vegetable extracts (cucumber, lettuce, apple, pear…) and environmental samples such as waters and soil extracts.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and application of molecularly imprinted polymers for the selective extraction of organophosphorus pesticides from vegetable oils

Boulanouar

Combès

Mezzache

et al. 2017

The increasing use of pesticides in agriculture causes environmental issues and possible serious health risks to humans and animals. Their determination at trace concentrations in vegetable oils constitutes a significant analytical challenge. Therefore, their analysis often requires both an extraction and a purification step prior to separation with liquid chromatography (LC) and mass spectrometry (MS) detection. This work aimed at developing sorbents that are able to selectively extract from vegetable oil samples several organophosphorus (OPs) pesticides presenting a wide range of physico-chemical properties. Therefore, different conditions were screened to prepare molecularly imprinted polymers (MIPs) by a non-covalent approach. The selectivity of the resulting polymers was evaluated by studying the OPs retention in pure media on both MIPs and non-imprinted polymers (NIP) used as control. The most promising MIP sorbent was obtained using monocrotophos (MCP) as the template, methacrylic acid (MAA) as the monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker with a molar ratio of 1/4/20 respectively. The repeatability of the extraction procedure and of the synthesis procedure was demonstrated in pure media. The capacity of this MIP was 1mg/g for malathion. This MIP was also able to selectively extract three OPs from almond oil by applying the optimized SPE procedure. Recoveries were between 73 and 99% with SD values between 4 and 6% in this oil sample. The calculated LOQs (between 0.3 and 2μg/kg) in almond seeds with a SD between 0.1 and 0.4μg/kg were lower than the Maximum Residue Levels (MRLs) established for the corresponding compounds in almond seed.