Vortex-Assisted Dispersive Micro-Solid Phase Extraction Using CTAB-Modified Zeolite NaY Sorbent Coupled with HPLC for the Determination of Carbamate Insecticides

Ecological impacts and management strategies of pesticide pollution on aquatic life and human beings

Pesticide contamination has become a global concern. Pesticides can sorb onto suspended particles and deposit into the sedimentary layers of aquatic environments, resulting in ecosystem degradation, pollution, and diseases. Pesticides impact the behavior of aquatic environments by contaminating organic matter in water, which serves as the primary food source for aquatic food webs. Pesticide residues can increase ammonium, nitrite, nitrate, and sulfate in aquatic systems; thus, threatening ecological environment and human health. Several physical, chemical, and biological methodologies have been implemented to effectively remove pesticide traces from aquatic environments. The present review highlights the potential consequences of pesticide exposure on fish and humans, focusing on the (epi)genetic alterations affecting growth, behavior, and immune system. Mitigation strategies (e.g., bioremediation) to prevent/minimize the detrimental impacts of pesticides are also discussed. This review aims to shed light on the awareness in reducing the risk of water pollution for safe and sustainable pesticide management.

Conjugated microporous polymer for solid-phase extraction of neonicotinoid insecticides from environmental water samples

Conjugated microporous polymers (CMPs) have unique characteristics and have been used in a range of fascinating applications in separation sciences. In this study, a CMP, designated as CMP-1, was synthesized via the Sonogashira-Hagihara coupling reaction using 1,3,5-triphenylbenzene and 1,4-dibromobenzene as building blocks. CMP-1 features a large surface area, abundant micropore structures, and excellent stability, making it a promising solid-phase extraction adsorbent for the efficient enrichment of neonicotinoid insecticides (NEOs). Under the optimized conditions, CMP-1 was combined with high-performance liquid chromatography and diode array detection to enable the detection of NEOs with a wide linear range (0.5-200 μg·L-1), a low detection limit (0.26-0.58 μg·L-1), and acceptable precision. The developed method was applied to determine spiked NEOs in three types of environmental water samples, with recoveries of 73.7%-112.0% and relative standard deviations of 0.6%-9.4%.

A zirconium metal-organic framework functionalized with a S/N containing carboxylic acid (MOF-808(Zr)-Tz) as an efficient sorbent for the ultrafast and selective dispersive solid phase micro extraction of chromium, silver, and rhodium in water samples

Metal-organic frameworks (MOFs) are good adsorbents for targeted chemicals with their adjustable properties. Herein, we prepared a zirconium based MOF (MOF-808(Zr)) and functionalized it employing 2-mercapto-4-methyl-5-thiazolacetic acid (MOF-808(Zr)-Tz). The prepared MOFs were characterized by XRD, FTIR, SEM-EDX, TGA, N2 sorption, zeta potential measurements, and elemental analysis. The surface area of MOF-808(Zr)-Tz was 1348 m2/g. Dispersive solid-phase micro-extraction (D-SPµE) method based on MOF-808(Zr)-Tz was firstly developed and applied to the extraction of chromium, silver, and rhodium in waters. The determination of the analytes was done by FAAS. The optimal pH and eluent for analytes were 7.0 and 3 mL of 2 mol L-1 HCl, respectively. The contact times were 1 min for adsorption and 3 min for elution. The LOD and PFs of the D-SPμE for analytes were 2.3 μg L-1 and 13.3 for chromium, 2.1 μg L-1 and 13.3 for silver, and 3.1 μg L-1 and 13.3 rhodium, respectively. The D-SPμE method was verified with analyses of NW-TMDA-54.6 Lake water and SPS-WW1 Batch 114 Wastewater and with spiked dam water, river water, well water, sea water, and wastewater. The recoveries of the analytes changed from 89 to 108 %. The results indicated that the method is selective, simple, effective, and rapid for extracting chromium(III), silver(I) and rhodium(III) in waters.

Vortex-assisted dispersive micro-solid-phase extraction using silica-supported Fe2O3-modified khat (Catha edulis) biochar nanocomposite followed by GC-MS for the determination of organochlorine pesticides in juice samples

In this paper, dispersive micro-solid phase extraction technique was developed for the purpose of extracting and preconcentrating organochlorine pesticide residues in juice samples before their separation and quantitative analysis by gas chromatography-mass spectrometry. A sorbent composed of a silica-supported Fe2O3-modified khat leftover biochar nanocomposite (SiO2-Fe2O3-KLBNC) was implemented in the process. To improve the dispersion of the sorbent in the solution, vortex mixer was employed. Experimental parameters influencing the performance of the method were optimized, and the optimal conditions were established. With these conditions, linear dynamic ranges ranged from 0.003 to 100.0 ng/mL were achieved, with a correlation coefficient (r2) ≥ 0.9981. The limits of detection and quantification, determined by signal-to-noise ratios of 3 and 10, respectively, were found to be in the ranges of 0.001-0.006 ng/mL and 0.003-0.020 ng/mL. Intra- and inter-day precision, values ranging from 0.3-4.8% and 1.7-5.2% were obtained, respectively. The matrix-matched extraction recoveries demonstrated favorable outcomes, falling within the range of 83.4-108.3%. The utilization of khat leftover as an adsorbent in contemporary sample preparation methodologies offers a cost-effective alternative to the currently available, yet expensive, adsorbents. This renders it economically viable, particularly in resource-constrained regions, and is anticipated to witness widespread adoption in the coming future.

Preparation of an efficient magnetic nano-sorbent based on modified cellulose and carboxylated carbon nano-tubes for extraction of pesticides from food and agricultural water samples before GC-FID analysis

This paper reports the direct synthesis approach of carboxamide functionalized magnetic nano-composite named Fe₃O₄@SiO₂-NH₂@dialdehyde cellulose (DAC)@CNT-COOH as an effectual sorbent for the co-extraction of seven agricultural insecticides and herbicides from vegetable, fruit, and water samples using the magnetic dispersive micro-solid-phase extraction procedure. Under the optimized extraction conditions (sorbent amount: 18.1 mg; desorption time: 6.5 min; desorption solvent volume: 185 μL; desorption solvent: acetonitrile; extraction time: 9.5 min; pH of sample solution: 7.0, and salt content: 5.0 % w/v sodium chloride), good linearity within the range 0.5-1200 ng/mL (R² ≥ 0.998) was achieved. Extraction efficiencies were in the range 63.4-84.1 %, the limits of detection were 0.08-1.0 ng/mL, and acceptable relative recoveries (87.6-103.8 %), and precisions were also achieved (RSDs < 6.8 %, n = 3). Ultimately, the obtained results showed that the developed method could be applied to determine trace amounts of desired analytes in various agricultural water and food samples.

Synthesis and hydrolysis of monocarbamate from allylic 1,4-dicarbamate: Bis-homodichloroinositol

The synthesis of novel bis-homodichloroinositol with a configuration similar to that of conduritol-D is reported for the first time. The photooxygenation of cis-dichloro-diene obtained using cyclooctatetraene as the starting molecule afforted the tricyclic endoperoxide. The reduction of the endoperoxide with thiourea gave the corresponding allylic cis-diol. Formation of the bis-carbamate groups with p-TsNCO of allylic cis-diol followed by the [(dba)₃Pd₂CHCl₃] in the presence of trimethylsilyl azide, gave a new monocarbamate as well as oxazolidinone derivative. Oxidation of the double bond in the monocarbamate with osmium tetraoxide followed by acetylation furnished the desired monocarbamate triacetate. Eventually, the desired halogenated bicyclo[4.2.0] inositol (bis-homodichloroinositol) were obtained in high yield by hydrolysis of the acetate groups and monocarbanate group by potassium carbonate in methanol. Characterization of all the synthesized compounds were performed by FT-IR, ¹H NMR, ¹³C NMR, COSY (2D-NMR), HRMS, and Elemental Analysis techniques.

Porous organic framework as coating for stir bar sorptive extraction of carbamate pesticides from corn and potato samples

Three porous organic frameworks (POFs) were synthesized by the reaction between phloroglucinol and 1,4-phthalaldehyde, 4,4'-biphenyldialdehyde or tris-(4-formylphenyl) amine; the products are named as POF-a, POF-b and POF-c, respectively. They were used to prepare POFs coated stir bars respectively for the extraction of four carbamate pesticides (CMPs). POF-c coated stir bar exhibited better adsorption performance than POF-a/b coated stir bar and commercial stir bars, probably due to the stronger conjugated structure and hydrophobicity of POF-c, and resultant hydrophobic, π-π and hydrogen bonding interactions between them. The adsorption mechanism for target CMPs was verified by characterization techniques and molecular dynamics simulation. A method of POF-c coated stir bar sorptive extraction-high performance liquid chromatography-variable wavelength ultraviolet detector was developed for the analysis of four CMPs in corn and potato samples. Under the optimal conditions, LODs of the method were between 0.017 and 0.048 μg/L, and the linear range for four CMPs was 0.1/0.2-200 μg/L.

Zeolite H-Beta as a Dispersive Solid-Phase Extraction Sorbent for the Determination of Eight Neonicotinoid Insecticides Using Ultra-High-Performance Liquid Chromatography—Tandem Mass Spectrometry

In this study, a dispersive solid-phase extraction (DSPE) pretreatment procedure using zeolite H-Beta as a sorbent was exploited for the determination of eight neonicotinoids in bottled water and honey products based on ultra-high-performance liquid chromatography–tandem mass spectrometry analysis. The zeolite H-Beta was demonstrated to be a suitable sorbent for neonicotinoid insecticides, even after 10 recycles of reuse. The method performance was evaluated by the linearity (R2 ≥ 0.998), recovery (71–108%), precision (0.1–7.8%), limit of detection (0.05–0.1 ng/mL) and limit of quantification (0.1–0.2 ng/mL), which suggested excellent stability and high sensitivity with the use of the DSPE procedure. The method was further successfully applied in the test of neonicotinoid insecticides in 34 samples. Zeolite H-Beta shows promise as an efficient and practical material for monitoring neonicotinoid insecticides in bottled water and multiplex honey matrices.

Efficient Extraction and Determination of Carbamate Pesticides in Vegetables Based on a Covalent Organic Frameworks with Acylamide Sites

It is an important challenge to effectively extract and determine pesticides in complex samples. Covalent organic frameworks (COFs) are burgeoning porous crystalline organic materials with good environmental resistance, thus demonstrating great potential as adsorbents in contaminants detection. In this work, we design and synthesize a novel COF-TpDB via 1,3,5-triformylphloroglucinol (Tp) and 4,4'-diaminobenzoylanilide (DB) as well as its packed cartridge for solid phase extraction (SPE) of carbamate pesticides. Simulation calculations showed H-bonding facilitates the adsorption interactions between the carbamate pesticides and TpDB. A method was developed by coupling TpDB as SPE sorbents with high performance liquid chromatography-ultraviolet (HPLC-UV) detection to determine trace carbamate pesticides in vegetables. The established method showed a wide linear range of 0.1-200 ng mL^-1 and low limit of detections (0.005-0.05 ng mL^-1) for four carbamate pesticides. The applicability of TpDB as adsorbent was investigated for determination of trace carbamate pesticides residue in vegetables with satisfactory recoveries of four carbamates in the range of 80.4-101.2%. The results demonstrated that the COF-TpDB offer great potential for efficient extraction of carbamate pesticides from complicate matrices.

Nanoplatform-Integrated Miniaturized Solid-Phase Extraction Techniques: A Critical Review

Preparation of the biological samples is one of the most critical steps in sample analysis. In past decades, the liquid-liquid extraction technique has been used to extract the desired analytes from complex biological matrices. However, solid-phase extraction (SPE) gained popularity due to versatility, simplicity, selectivity, reproducibility, high sample recovery %, solvent economy, and time-saving nature. The superior extraction efficiency of SPE can be attributed to the development of advanced techniques, including the nanosorbents technology. The nanosorbent technology significantly simplified the sample preparation, improved the selectivity, diversified the application, and accelerated the sample analysis. This review critically expands on the to-date advancements reported in SPE with particular regards to the nanosorbent technology.

Review: Microextraction Technique Based New Trends in Food Analysis

Food chemistry is the study and classification of the quality and origin of foods. The identification of definite biomarkers and the determination of residue contaminants such as toxins, pesticides, metals, human and veterinary drugs, which are a very common source of food-borne diseases. The food analysis is continuously demanding the improvement of more robust, sensitive, highly efficient, and economically beneficial analytical approaches to promise the traceability, safety, and quality of foods in the acquiescence with the consumers and legislation demands. The traditional methods have been used at the starting of the 20th century based on wet chemical methods. Now it existing the powerful analytical techniques used in food analysis and safety. This development has led to substantial enhancements in the analytical accuracy, precision, sensitivity, selectivity, thereby mounting the applied range of food applications. In the present decade, microextraction (micro-scale extraction) pays more attention due to its futures such as low consumption of solvent and sample, throughput analysis easy to operate, greener, robotics, and miniaturization, different adsorbents have been used in the microextraction process with unique nature recognized with wide range applications.

Chemical Fixation of CO2 Using Highly Dispersed Cu on Hierarchically Porous N-Doped Carbon

Chemical transformation of carbon dioxide (CO₂) into fine chemicals such as oxazolidinones and carbamates is mainly reported using transition-metal complexes as homogeneous catalysts. Herein, we demonstrate that a heterogeneous catalyst of highly dispersed Cu (Cu/NHPC) supported on hierarchically porous N-doped carbon (NHPC) can efficiently promote CO₂ fixations to oxazolidinones and β-oxopropylcarbamates. The obtained NHPC, assembled by ultrathin nitrogen-doped carbon nanosheets with a three-dimensional (3D) structure, is readily prepared by pyrolysis of a nitrogen-containing polymer gel (NPG) in the presence of an activator of potassium bicarbonate (KHCO₃). The resulting NHPC shows specific Brunauer-Emmet-Teller (BET) surface areas up to 2054 m² g^-1 with a mean micro/mesopore size of 0.55/3.2 nm and a broad macropore size distribution from 50 to 230 nm. The Cu/NHPC can efficiently promote three-component coupling of CO₂, amines, and propargyl alcohols for syntheses of various oxazolidinones and β-oxopropylcarbamates with yields up to 99% and a wide substrate scope. Moreover, the Cu/NHPC exhibits excellent recyclability in CO₂-to-oxazolidinone transformation during nine-time recycling. The research thus develops an NHPC-based heterogeneous Cu catalyst for green transformation of CO₂.

Magnetic metal organic framework for pre-concentration of ampicillin from cow milk samples

The aim of this study is a present of a simple solvothermal synthesis approach to preparation of Cu-based magnetic metal organic framework (MMOF) and subsequently its application as sorbent for ultrasound assisted magnetic solid phase extraction (UAMSPE) of ampicillin (AMP) from cow milk samples prior to high performance liquid chromatography-Ultraviolet (HPLC-UV) determination. Characteristics of prepared MMOF were fully investigated by different techniques which showed the exclusive properties of proposed sorbent in terms of proper functionality, desirable magnetic property and also high specific surface area. Different influential factors on extraction recovery including sorbent dosage, ultrasonic time, washing solvent volume and eluent solvent volume were assessed using central composite design (CCD) based response surface methodology (RSM) as an operative and powerful optimization tool. This is the first report for determination of AMP using MMOF. The proposed method addressed some drawbacks of other methods and sorbents for determination of AMP. The presented method decreases the extraction time (4 min) and also enhances adsorption capacity (250 mg/g). Moreover, the magnetic property of presented sorbent (15 emu/g) accelerates the extraction process which does not need filtration, centrifuge and precipitation procedures. Under the optimized conditions, the proposed method is applicable for linear range of 1.0–5000.0 μg/L with detection limit of 0.29 μg/L, satisfactory recoveries (≥95.0%) and acceptable repeatability (RSD less than 4.0%). The present study indicates highly promising perspectives of MMOF for highly effective analysis of AMP in complicated matrices.

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MMOF was prepared and used for the first time for determination of ampicillin from cow milk samples.

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The extraction method was convenient, rapid and the MMOF can be used more than 8 times.

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The MMOF have high specific surface area (300.0 m²/g) and high adsorption capacity (250.5 mg g⁻¹).

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The separation time was only 5 min, which was much shorter than other reported.

Organic Analysis of Environmental Samples Using Liquid Chromatography with Diode Array and Fluorescence Detectors: An Overview

This overview is focused to provide an useful guide of the families of organic pollutants that can be determined by liquid chromatography operating in reverse phase and ultraviolet/fluorescence detection. Eight families have been classified as the main groups to be considered: carbonyls, carboxyls, aromatics, phenols, phthalates, isocyanates, pesticides and emerging. The references have been selected based on analytical methods used in the environmental field, including both the well-established procedures and those more recently developed.

Zeolites and zeolite-based materials in extraction and microextraction techniques

This review presents an overview of the current status of zeolites and zeolite-based materials used in extraction and microextraction techniques with reference to recent applications and highlight some of the novel advances.

Cationic gemini surfactant-resorcinol-aldehyde resin and its application in the extraction of endocrine disrupting compounds from food contacting materials

A new cationic gemini surfactant-resorcinol/formaldehyde resin was designed and synthesized. Cationic gemini surfactant was introduced into the resorcinol/formaldehyde resin for the first time and led to the retention of negatively charged endocrine disrupting compounds (EDCs) through electrostatic interactions, hydrogen bonding and π-π interactions. The synthesized material showed good performance in the dispersive micro-solid phase extraction (D-μ-SPE) of EDCs such as alkylphenol and phenoxy acid herbicides from food packaging migrants. Extraction parameters such as pH, adsorbent dose, extraction time and salting out effect were optimized. The limits of detections were in the range of 0.5-0.8 ng/mL, and the recoveries were in the range of 90-100%. The developed method was applied to the analysis of EDCs from food contacting materials migrants with pentachlorophenol, 2,4-dichlorophenoxyacetic acid and bisphenol A detected in the concentration range of 0.2-1.2 mg/kg. It also showed great potential in the D-μ-SPE of other compounds with negative charge or high hydrophobicity.

Recent Modifications and Validation of QuEChERS-dSPE Coupled to LC-MS and GC-MS Instruments for Determination of Pesticide/Agrochemical Residues in Fruits and Vegetables: Review

Fruits and vegetables constitute a major type of food consumed daily apart from whole grains. Unfortunately, the residual deposits of pesticides in these products are becoming a major health concern for human consumption. Consequently, the outcome of the long-term accumulation of pesticide residues has posed many health issues to both humans and animals in the environment. However, the residues have previously been determined using conventionally known techniques, which include liquid-liquid extraction, solid-phase extraction (SPE) and the recently used liquid-phase microextraction techniques. Despite the positive technological effects of these methods, their limitations include; time-consuming, operational difficulty, use of toxic organic solvents, low selective property and expensive extraction setups, with shorter lifespan of instrumental performances. Thus, the potential and maximum use of these methods for pesticides residue determination has resulted in the urgent need for better techniques that will overcome the highlighted drawbacks. Alternatively, attention has been drawn recently towards the use of quick, easy, cheap, effective, rugged and safe technique (QuEChERS) coupled with dispersive solid-phase extraction (dSPE) to overcome the setback challenges experienced by the previous technologies. Conclusively, the reviewed QuEChERS-dSPE techniques and the recent cleanup modifications justifiably prove to be reliable for routine determination and monitoring the concentration levels of pesticide residues using advanced instruments such as high-performance liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry.

Preconcentration of Trace Neonicotinoid Insecticide Residues Using Vortex-Assisted Dispersive Micro Solid-Phase Extraction with Montmorillonite as an Efficient Sorbent

In this work, we investigated montmorillonite for adsorption of neonicotinoid insecticides in vortex-assisted dispersive micro-solid phase extraction (VA-d-μ-SPE). High-performance liquid chromatography with photodiode array detection was used for quantification and determination of neonicotinoid insecticide residues, including thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid. In this method, the solid sorbent was dispersed into the aqueous sample solution and vortex agitation was performed to accelerate the extraction process. Finally, the solution was filtered from the solid sorbent with a membrane filter. The parameters affecting the extraction efficiency of the proposed method were optimized, such as amount of sorbent, sample volume, salt addition, type and volume of extraction solvent, and vortex time. The adsorbing results show that montmorillonite could be reused at least 4 times and be used as an effective adsorbent for rapid extraction/preconcentration of neonicotinoid insecticide residues. Under optimum conditions, linear dynamic ranges were achieved between 0.5 and 1000 ng mL^-1 with a correlation of determination (R²) greater than 0.99. Limit of detection (LOD) ranged from 0.005 to 0.065 ng mL^-1, while limit of quantification (LOQ) ranged from 0.008 to 0.263 ng mL^-1. The enrichment factor (EF) ranged from 8 to 176-fold. The results demonstrated that the proposed method not only provided a more simple and sensitive method, but also can be used as a powerful alternative method for the simultaneous determination of insecticide residues in natural surface water and fruit juice samples.

A four-component coupling reaction of carbon dioxide, amines, cyclic ethers and 3-triflyloxybenzynes for the synthesis of functionalized carbamates

A novel four-component coupling reaction of carbon dioxide, amines, cyclic ethers and 3-triflyloxybenzynes for the synthesis of functionalized carbamates has been developed for the first time.

Advances in organic-inorganic hybrid sorbents for the extraction of organic and inorganic pollutants in different types of food and environmental samples

The efficiency of the extraction and removal of pollutants from food and the environment has been an important issue in analytical science. By incorporating inorganic species into an organic matrix, a new material known as an organic-inorganic hybrid material is formed. As it possesses high selectivity, permeability, and mechanical and chemical stabilities, organic-inorganic hybrid materials constitute an emerging research field and have become popular to serve as sorbents in various separaton science methods. Here, we review recent significant advances in analytical solid-phase extraction employing organic-inorganic composite/nanocomposite sorbents for the extraction of organic and inorganic pollutants from various types of food and environmental matrices. The physicochemical characteristics, extraction properties, and analytical performances of sorbents are discussed; including morphology and surface characteristics, types of functional groups, interaction mechanism, selectivity and sensitivity, accuracy, and regeneration abilities. Organic-inorganic hybrid sorbents combined with extraction techniques are highly promising for sample preparation of various food and environmental matrixes with analytes at trace levels.