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Efficiently detecting diamide insecticides in environmental water is challenging due to their low concentrations and complex matrix interferences. In this study, we developed ionic liquids (ILs)-incorporated magnetic molecularly imprinted polymers (IL-MMIPs) for the detection of diamide insecticides, capitalizing on the advantages of ILs and quick magnetic separation through surface imprinting. Tetrachlorantraniliprole was used as the template, and a specific IL, 1-vinyl-3-ethylimidazolium hexafluorophosphate ([VEIm][PF 6 ]), was employed as the functional monomer. Various synthesis conditions were investigated to optimize adsorption efficiency. The prepared IL-MMIPs were successfully employed as adsorbents in magnetic solid-phase extraction (MSPE) to selectively extract, separate, and quantify three types of diamide insecticides from water samples using HPLC-UV detection. Under optimal conditions, the analytical method achieved low limits of detection (0.69 ng mL -1 , 0.64 ng mL -1 , 0.59 ng mL -1 for cyantraniliprole, chlorantraniliprole and tetrachlorantraniliprole, respectively). The method also displayed a wide linear range (0.003-10 μg mL -1 for cyantraniliprole and chlorantraniliprole, and 0.004-10 μg mL -1 for tetrachlorantraniliprole, respectively) with satisfactory coefficients (R 2 ≥0.9996), and low relative standard deviation (RSD≤2.55%). Additionally, extraction recoveries fell within the range of 79.4%-109%. The results clearly demonstrate that IL-MMIPs exhibit exceptional recognition and rebinding capabilities. The developed IL-MMIPs-MSPE-HPLC-UV method is straightforward and rapid, making it suitable for the detection and analysis of three kinds of diamide insecticides in environmental water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A rapid and economic integrated solid-phase extraction (ISPE) method with ionic liquid-thiol-graphene oxide composite (IL-TGO) as a new adsorbent was established for the extraction of fipronil in chicken eggs. In this study, ISPE, a new form of solid-phase extraction, which combined the advantages of pipette-tip solid phase extraction (PT-SPE) and dispersive solid-phase extraction (DSPE), achieving rapid extraction of analyte with only a small amount of adsorbent. The three-dimensional porous IL-TGO was a new ideal adsorbent for fipronil due to the multiple adsorption interactions (π-π interaction, hydrophobic interaction and hydrogen bond), large adsorption capacity and fast adsorption rate. For this ISPE procedure, the analyte was adsorbed by IL-TGO through the pipette tip mode and then eluted through dispersive mode. Under the optimized condition, the proposed method performed following merits: good linearity (r = 0.9999), precision (RSD ≤ 6.3%), high recoveries (83.7% to 97.7%), rapid extraction (16 min), low consumption of adsorbent (3.00 mg of IL-TGO). The excellent recyclability of the ISPE device and the reusability of IL-TGO were observed and high recovery of fipronil (> 90%) was obtained after fifteen cycles. This work might provide promising strategy for the sensitive extraction and analysis of trace levels of fipronil from egg products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier B.V.)

A deep eutectic solvent functionalized graphene oxide composite adsorbent (DFG) was synthesized through reversible-addition fragmentation chain-transfer polymerization. The synthesized DFG had multiple adsorption interactions after covalent modification with a deep eutectic solvent (allyltriethylammonium bromide/ethylene glycol). Adsorption isotherms and kinetics studies of DFG indicate that the adsorption of hippuric acid (HA) and methylhippuric acid (MHA) was monolayer chemical adsorption. The comparison of DFG with commercial adsorbents demonstrates that the adsorption ability of DFG was superior. This was due to the multiple adsorption interactions of DFG for the three analytes (mainly π-interaction, hydrogen bonding, electrostatic adsorption, and hydrophobic interaction). The DFG adsorbent was applied to miniaturized pipette-tip solid-phase extraction (MPT-SPE), followed by high-performance liquid chromatography (HPLC) to determine biomarkers in urine for toluene and xylene exposure. The DFG-MPT-SPE-HPLC method required only 2.00 mg of DFG as adsorbent, 0.50 mL of washing solvent, and 0.40 mL of elution solvent to achieve a wide linear range (0.200-200 μg mL -1 ), high recoveries (90.9-99.1%), and high precision (RSD ≤ 6.3%). The proposed method was applied to determine HA and MHA in urine samples from occupational workers. Graphical abstract Deep eutectic solvent functionalized graphene oxide composite adsorbent for miniaturized pipette-tip solid-phase extraction of toluene and xylene exposure biomarkers in urine prior to their determination with HPLC-UV.

A new ionic liquid functionalized graphene-pipette-tip solid-phase extraction method coupled with high-performance liquid chromatography was established for the simultaneous extraction and determination of three auxins in soybean sprouts. The graphene adsorbent, with multiple adsorption mechanisms, was first synthesized by functional modification of pentafluorobenzyl imidazolium bromide ionic liquid through thiol-ene click chemistry. The ionic liquid was applied to prevent the aggregation of graphene; it also imbued graphene with the ability for π-π interactions, ionic exchange, electrostatic interactions, as well as hydrogen bonding (which is stronger than the interaction between water and analytes), by augmenting the adsorption mechanisms between the adsorbent and analytes. Under optimized conditions, linearity was achieved in the ranges 0.03-5.00 µg/g for indole-3-acetic acid and 1-naphthaleneacetic acid and 0.09-5.00 µg/g for 2,4-dichlorophenoxyacetic acid, with a detection limit of 0.004-0.026 µg/g; this adsorbent has been successfully applied for the determination of auxins in soybean sprouts., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

An ionic-liquid-based polymer monolithic column was synthesized by free radical polymerization within the confines of a stainless-steel column (50 mm × 4.6 mm id). In the processes, ionic liquid and stearyl methacrylate were used as dual monomers, ethylene glycol dimethacrylate as the cross-linking agent, and polyethylene glycol 200 and isopropanol as co-porogens. Effects of the prepolymerization solution components on the properties of the resulting monoliths were studied in detail. Scanning electron microscopy, nitrogen adsorption-desorption measurements, and mercury intrusion porosimetry were used to investigate the morphology and pore size distribution of the prepared monoliths, which showed that the homemade ionic-liquid-based monolith column possessed a relatively uniform macropore structure with a total macropore specific surface area of 44.72 m 2 /g. Compared to a non-ionic-liquid-based monolith prepared under the same conditions, the ionic-liquid-based monolith exhibited excellent selectivity and high performance for separating proteins from complex biosamples, such as egg white, snailase, bovine serum albumin digest solution, human plasma, etc., indicating promising applications in the fractionation and analysis of proteins from the complex biosamples in proteomics research., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A sensitive determination method was developed for the analysis of pyrethroid pesticide residues in tomato samples using ionic liquid-based dispersive liquid-liquid microextraction. A hydrophobic ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) and acetonitrile were used as the extraction solvent and dispersive solvent, respectively. The following experimental parameters affecting the extraction efficiency were examined: types of extraction solvent and volume of extraction solvent, types of dispersive solvent and volume of dispersive solvent and pH and ion strength of the sample solution. Under the optimum conditions, the extraction recoveries ranged from 83.9 to 96.7%. Moreover, the enrichment factors for esbiothrin, fenpropathrin and cyhalothrin were 42, 48 and 45, respectively. The calibration curves were linear with correlation coefficients ranging from 0.9997 to 0.9999 at concentrations of 0.05-1.5 µg/kg. The relative standard deviation (n = 5) was 1.7-4.5%. The limits of detection for esbiothrin, fenpropathrin and cyhalothrin were 8.1, 9.9 and 14.3 µg/kg, respectively.

Ionic liquids (ILs) are novel nonmolecular solvents. Their unique properties, such as high thermal stability, tunable viscosity, negligible vapor pressure, nonflammability, and good solubility for inorganic and organic compounds, make them excellent candidates as extraction media for a range of microextraction techniques. Many physical properties of ILs can be varied, and the structural design can be tuned to impart the desired functionality and enhance the analyte extraction selectivity, efficiency, and sensitivity. This paper provides an overview of the applications of ILs in liquid phase microextraction technology, such as single-drop microextraction, hollow fiber based liquid phase microextraction, and dispersive liquid-liquid microextraction. The sensitivity, linear calibration range, and detection limits for a range of target analytes in the methods were analyzed to determine the advantages of ILs in liquid phase microextraction., (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Ionic liquids are a class of organic salts with melting points equal to or below 100 °C, and their use in sample preparation has shown its promise, for example, in alleviation of environmental pollution and improvement of selectivity and extraction of certain interesting compounds., Results: Optimal conditions were obtained by using 1.0 mol L(-1) 1-butyl-3-methylimidazolium methylsulfate ([Bmim][MS]) aqueous solution at pH 1.0 as the extraction solvent. An ultrasonic power of 200 W was chosen to ensure complete dispersion of [Bmim][MS] into celery in 90 min and the solid:liquid ratio was 1:10., Conclusion: The proposed ultrasonic assistant extraction approach, based on ionic liquid aqueous solution, exhibited satisfactory results, with recovery values ranging from 72.7% to 89.5%. Under optimal conditions, compared with conventional solvent extraction amounts of luteolin and apigenin were more than doubled., (Copyright © 2011 Society of Chemical Industry.)

Ionic liquid-based dispersive liquid-liquid microextraction was developed for the extraction and preconcentration of aromatic amine from environmental water. A suitable mixture of extraction solvent (100 μL, 1-butyl-3-methylimidazolium hexafluorophoshate) and dispersive solvent (750 μL, methanol) were injected into the aqueous samples (10.00 mL), forming a cloudy solution. After centrifuging, enriched analytes in the sediment phase were determined by HPLC-UV. The effect of various factors, such as the extraction and dispersive solvent, sample pH, extraction time and salt effect were investigated. Under optimum conditions, enrichment factors for 2-anilinoethanol, o-chloroaniline and 4-bromo-N,N-dimethylaniline were above 50 and the limits of detection (LODs) were 0.023, 0.015 and 0.026 ng/mL, respectively. Their linear ranges were 0.8-400 ng/mL for 2-anilinoethanol, 0.5-200 ng/mL for o-chloroaniline and 0.4-200 ng/mL for 4-bromo-N,N-dimethylaniline, respectively. Relative standard deviations (RSDs) were below 5.0%. The relative recoveries from samples of environmental water were in the range of 82.0-94.0%. Compared with other methods, dispersive liquid-liquid microextraction is simple, rapid, sensitive and economical., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ionic liquids (ILs) have been applied in different areas of separation, such as ionic liquid supported membranes, as mobile phase additives and surface-bonded stationary phases in chromatography separations and as the extraction solvent in sample preparations, because they can be composed from various cations and anions that change the properties and phase behavior of liquids. Although the applications of ILs in separations are still in their early stages, the academic interest in ILs is increasing. An overview of the principle applications of ILs in separation technology is present in this work. Furthermore, the prospects of the ILs in separation techniques are discussed.

A novel ionic liquid modified polymer was employed as an adsorbent for dispersive solid phase extraction for the determination of cyanazine and atrazine in tomatoes. This polymer was advantageous over conventional solid phase extraction in terms of the operational simplicity, speed, handling of large sample volumes, and recovery. Extraction parameters, such as the adsorbent amount, adsorbent time, elution solvent, elution time, and pH of aqueous samples were optimized. The optimized extraction conditions included 50 mg of 1-ethyl-3-methylimidazolium bromide modified polymer as the adsorbent, dichloromethane as the eluent, and 6 min as the adsorption time. Under the optimized conditions, the recovery from tomato samples ranged from 72.0 to 95.1%, which was comparable to tomato juice. The limits of detection for cyanazine and triazine were 0.51 ng/mL and 0.35 ng/mL, respectively. [ABSTRACT FROM AUTHOR]

A new hollow fibre liquid phase microextraction technology with an ionic liquid as the carrier was developed to determine the fluoroquinolone antibiotics in milk. In this technology, a porous polypropylene hollow fibre was filled with aqueous ionic liquid and the extraction efficiency of different factors, such as the type of hollow fibre membrane carrier, the pH and ionic strength of the donor solution, the pH of the acceptor solution, the stirring rate and the extraction time, were investigated. The optimised extraction condition was: [OMim][BF4] impregnated in the pores of the hollow fibre; 0.1 mol L−1 of Na2HPO4 (pH 11.0) as the acceptor solution was injected into the lumen of the hollow fibre; 0.1 mol L−1 H3PO4 (pH 5.0) was used as the donor solution; 600 rpm was selected as the stirring rate; 120 min was the optimum extraction time. The proposed method provided very high factors with 130-fold, 156-fold and 116-fold enrichment of ofloxacin, ciprofloxacin and enrofloxacin, respectively. [ABSTRACT FROM AUTHOR]

The retentions of five β-Lactam antibiotics were analyzed by reversed-phased high-performance liquid chromatography. The mobile phase was acetonitrile/water (15/85, v/v) and the absorption wavelength was determined at 254 nm. When 1-butyl-3-methylimidazolium tetrafluoroborate was added into the mobile phase as additive, the samples were well separated with sharper peaks. The optimal concentration of 1-butyl-3-methylimidazolium tetrafluoroborate at pH 3 was 1.0 mM. The pH has large effect on the retention that the retention factor increasing with the pH of the mobile phase increasing. Three types of 1-alkyl-3-methylimidazolium-based ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate, and 1-octyl-3-methylimidazolium tetrafluoroborate) were used and compared as additives in the mobile phase. The results showed that the retention time increased with increasing alkyl chain length. Among the three ionic liquids, the optimal effective additive was 1-butyl-3-methylimidazolium tetrafluoroborate. [ABSTRACT FROM AUTHOR]

It is extremely significant while challenging to accurately detect low-levels of perfluoroalkyl carboxylic acid compounds (PFCAs) in environmental water. Herein, adopting perfluorotetradecanoic acid as the dummy template, selective molecularly imprinted composites (CNTs@ILs@MIPs) grafted carbon nanotubes integrating hydrophilic ionic liquids were successfully prepared via surface imprinting and dummy-template imprinting techniques. The obtained CNTs@ILs@MIPs were applied as selective extraction adsorbent for specifically extract PFCAs in environmental water coupled with gas chromatography-mass spectrometry quantification. Detailed studies were conducted on the main preparation parameters and extraction conditions. The CNTs@ILs@MIPs displayed excellent adsorptivity, and the established method exhibited low LODs (0.60–1.64 ng L−1), wide linearity with R 2 above 0.9994, and satisfactory adsorption recoveries (80.5–112.5%) for seven PFCAs. This proposed method provides a new applicable approach for the detection of targeted pollutants in environmental water by utilizing the high affinity and recognition ability of molecularly imprinted carbon nanotube functional materials modified with ionic liquids. [Display omitted] • Perfluoroalkyl carboxylic acid (PFCAs)-imprinted carbon nanotubes integrating ionic liquids (CNTs@ILs@MIPs) were synthesized via surface imprinting and dummy-template imprinting techniques. • The CNTs@ILs@MIPs possessed excellent adsorbability and fast kinetics. • The established method was sensitive and practical for seven PFCAs in environmental water. [ABSTRACT FROM AUTHOR]

• A new imidazolium-based metal-organic framework named HBU-167 was synthesized. • Imidazole/pyridine-based ionic liquids and HBU-167 were combined to form IL@HBU-167. • HBU-167 and IL@HBU-167 were examined as adsorbents for removal of congo red in water. • Addition of ionic liquids enhanced structural stability and adsorption capacity. • The adsorption mechanism and effects of experimental conditions were examined. In this work, a metal-organic framework (MOF), {[Ba 2 L(NO 3) (DMF) 2 ] (DMF·H 2 O)} n , denoted as HBU-167, was synthesized under solvothermal conditions. HBU-167 obtained a 3D layer framework comprising the imidazole carboxylic acid ligand and Ba2+ as nodes. It was demonstrated to have an adsorption capacity for Congo red (CR), with an adsorption capacity of 407.37 mg•g−1 and a removal rate of 65.46 %. To improve the adsorption capacity of HBU-167, simply impregnated three imidazole/pyridine-based ionic liquids (ILs) onto HBU-167 to obtain IL@HBU-167 for efficient CR adsorption. The results of Powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy revealed that ILs successfully bonded to HBU-167. Adsorption experiments on CR revealed that IL@HBU-167 exhibited increased stability as well as improved adsorption capacity. The adsorption capabilities of the IL@HBU-167 were 440.70 mg•g−1, 491.23 mg•g−1, and 544.56 mg•g−1, respectively, while the removal rates were 72.96 %, 75.00 %, and 83.28 %, respectively. Batch experiments were applied to analyze the impact of factors such as contact time, initial concentration, pH, temperature, and ionic strength on the adsorption of CR by IL@HBU-167. The maximum adsorption capacity was observed at 25 °C and pH = 6. The kinetic data indicated that the adsorption conformed to the pseudo-second-order kinetic model. The Langmuir isothermal model accurately described isothermal data. Furthermore, the adsorption capacity of IL@HBU-167 was investigated in real water samples from various sources. The results showed that IL@HBU-167 can be used as an innovative and inexpensive adsorbent for the removal of CR from water. The adsorption capacity was mainly derived from π-π, electrostatic interactions, and hydrogen bonding between IL@HBU-167 and CR. Ba (II) MOF (HBU 167) based on an imidazole functionalized carboxylate ligand was synthesized and characterized. Highly efficient adsorbent obtained by simple impregnation of three imidazole/pyridine-based ionic liquids (ILs) onto HBU-167. The incorporation of ILs increases the stability of the original material as well as its ability to adsorb Congo red in water. [Display omitted] [ABSTRACT FROM AUTHOR]