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Solid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas-solid phase and liquid-solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward packed sorbent SPE devices. Without any doubt, the heart of the SPE technique is the sorbent material as it has a direct influence on the selectivity, sorptive capacity, and the format or the configuration of the resultant SPE device. There will always be a need for new sorbent materials, and therefore, it is imperative to focus research efforts on versatile sorbent fabrication techniques that could address current and anticipated challenges. Various polymeric materials have been developed and implemented in everyday life. They are also extensively used in analytical chemistry. This review provides an updated summary of the most important features of polymeric sorptive materials used at the stage of preparing samples for analysis. The application of each new polymeric sorbent material is discussed in detail. Moreover, the comparison between these materials is done.

In this work, a novel methodology based on the combination of MIP technology with micro solid-phase extraction in a hollow fibre device for the trace enrichment and cleanup of triazines in environmental waters is described. All parameters affecting both migration of triazines from samples to the lumen of the fibre and rebinding into MIP sites have been carefully optimized. Final conditions included, addition of 20% NaCl to the sample to produce salting-out effect, extraction of analytes during 45min with orbital stirring at 750rpm, and then washing the fibre with toluene during 5min to allow selective recognition of triazines before elution in HPLC inserts containing 450μL of a methanol/acetic acid mixture (95/5, v/v). Under optimum conditions, quantitative recoveries for simazine, cyanazine, atrazine, propazine and terbutylazine, were achieved both in surface, ground and tap water samples, with relative standard deviations lower than 10.6%, and limits of detection in the low ngL(-1) concentration level., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work, molecularly imprinted polymer (MIP) beads have been prepared and evaluated for the development of a supported liquid membrane-protected micro-solid phase extraction method for the analysis of sulfonamides (SAs) in aqueous samples. The performance of MIP beads was firstly evaluated in cartridges by conventional solid-phase extraction for the simultaneous analysis of SAs. Afterward, beads were packed into a polypropylene hollow fiber protected by an organic solvent immobilized in the pores of the capillary wall. During the process, the analytes were extracted from the aqueous sample to the immobilized organic solvent and then selectively retained by the MIP beads located inside the capillary. The effect of various experimental parameters as sample pH, time and stirring-rate among others, were studied for the establishment of optimum rebinding conditions. Relative recoveries for all sulfonamides tested in river and reservoir water samples by the proposed method using 100mL water sample spiked with 50μg L-1 of each sulfonamide were within 70-120%, with a relative standard deviation (RSD) <10% (n=3). The detection limits (LODs) were within 0.2-3μgL(-1), depending upon the sulfonamide and the type of water used., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this study, we designed a molecularly imprinted polymers-dispersive solid-phase extraction-high-performance liquid chromatography (MIPs-DSPE-HPLC) method, as a simple and efficient platform for the sensitive detection of two sulfonamide antibiotics (SAs) of sulfamethoxine (SMM) and sulfamethoxazole (SMZ) in environmental water samples. Using SMM and SMZ as templates, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the crosslinking agent, and azodiisobutyronitrile as the catalyst, the dual-template molecularly imprinted polymers (dt-MIPs) were successfully synthesized via surface imprinting technology and multi-template imprinting strategy. The adsorption properties of the prepared MIPs were characterized, and the adsorption capacities of MIPs towards SMZ and SMM were 27.35 mg/g and 30.92 mg/g, respectively. The detection limits of the method in three environmental water samples were in the range of 0.23–1.74 μg/L, and the recoveries were between 82.7 and 110.3%, with relative standard deviations less than 5.93%. The construction process of this MIPs-DSPE-HPLC method is straightforward, exhibits high sensitivity and selectivity, and thus provides a versatile method for the quantification of SAs in complex matrices. [ABSTRACT FROM AUTHOR]

Indacaterol, a β2 agonist prescribed for long-term management of patients with chronic obstructive pulmonary disease and asthma. In this study the first MISPE cartridges was developed using indacaterol as a template for its selective extraction from rat lung tissues, enabling precise pharmacokinetic evaluation at the drug's site of action. A molecular imprinting polymer was synthesized using indacaterol as a template, methacrylic acid as a functional monomer and ethylene glycol dimethacrylate as a cross-linker with a molar ratio (1: 4: 20). The polymer was characterized by a high binding capacity of 9840 ± 0.86 and high selectivity with an imprinting factor of 4.53 ± 0.12. The synthesized polymer was utilized as a sorbent in solid-phase extraction to purify and extract indacaterol from lung tissue matrix. The optimum molecularly imprinted solid-phase extraction (MISPE) conditions were 20.0 mg of molecular imprinting polymer and non-imprinting polymer, acetonitrile as the loading solvent, acetonitrile: water (20: 80; by volume) as the washing solvent, and methanol: acetic acid (90: 10; by volume) as the eluting solvent. A pharmacokinetic study was performed for indacaterol in rat lungs using the synthesized and optimized MISPE cartridge as a tool for sample purification. These parameters were determined in the lung tissues of rats emphasizing the local exposure of indacaterol to its target organ. The Cmax and Tmax were 51.020 ± 2.810 µg mL− 1 and 0.083 ± 0.001 h, respectively. The AUC 0−24 and AUC0 − inf were 175.920 ± 1.053 and 542.000 ± 5.245 µg h mL− 1, respectively. The elimination rate constant was 0.014 ± 0.00012 h− 1 and the half-life time was 48.510 ± 0.012 h. This study successfully developed and optimized MISPE cartridges using indacaterol as a template, enabling precise pharmacokinetic evaluation in rat lung tissues. The cartridges demonstrated high binding capacity and selectivity, providing crucial insights into the local exposure of indacaterol at its site of action. [ABSTRACT FROM AUTHOR]

A functional material was developed with specific recognition properties for aflatoxins for pre-processing enrichment and separation in the detection of aflatoxins in Chinese herbal medicines. In the experiment, ethyl coumarin-3-carboxylate, which has a highly similar structure to the oxonaphthalene o-ketone of aflatoxin, was selected as a pseudo-template, zinc acrylate, neutral red derivative, and methacrylic acid, which have complementary functions, were selected as co-monomers to prepare a pseudo-template multifunctional monomer molecularly imprinted polymer (MIP). The MIP obtained under the optimal preparation conditions has a maximum adsorption capacity of 0.036 mg/mg and an imprinting factor of 3.67. The physical property evaluation of the polymers by Fourier infrared spectrometer, scanning electron microscopy, pore size analyzer, thermogravimetric analyzer, and diffuse reflectance spectroscopy showed that the MIP were successfully prepared and porous spherical-like particles were obtained. The synthesized polymer was used as a solid-phase extraction agent for the separation of aflatoxins from the extract of spina date seed. The linear range of the developed method was 10–1000 ng/mL, the limit of detection was 0.36 ng/mL, the limit of quantification was 1.19 ng/mL, and the recoveries of the extracts at the concentration level of 0.2 μg/mL were in the range 88.0–93.4%, with relative standard deviations (RSDs) of 1.97% (n). The results showed that the preparation of MIPs using ethyl coumarin-3-carboxylate as a template was simple, economical, and convenient. It is expected to become a promising functional material for the enrichment and separation aflatoxins from complex matrices. [ABSTRACT FROM AUTHOR]

Despite advancements in the sensitivity and performance of analytical instruments, sample preparation remains a bottleneck in the analytical process. Currently, solid-phase extraction is more widely used than traditional organic solvent extraction due to its ease of use and lower solvent requirements. Moreover, various microextraction techniques such as micro solid-phase extraction, dispersive micro solid-phase extraction, solid-phase microextraction, stir bar sorptive extraction, liquid-phase microextraction, and magnetic bead extraction have been developed to minimize sample size, reduce solvent usage, and enable automation. Among these, in-tube solid-phase microextraction (IT-SPME) using capillaries as extraction devices has gained attention as an advanced "green extraction technique" that combines miniaturization, on-line automation, and reduced solvent consumption. Capillary tubes in IT-SPME are categorized into configurations: inner-wall-coated, particle-packed, fiber-packed, and rod monolith, operating either in a draw/eject system or a flow-through system. Additionally, the developments of novel adsorbents such as monoliths, ionic liquids, restricted-access materials, molecularly imprinted polymers (MIPs), graphene, carbon nanotubes, inorganic nanoparticles, and organometallic frameworks have improved extraction efficiency and selectivity. MIPs, in particular, are stable, custom-made polymers with molecular recognition capabilities formed during synthesis, making them exceptional "smart adsorbents" for selective sample preparation. The MIP fabrication process involves three main stages: pre-arrangement for recognition capability, polymerization, and template removal. After forming the template-monomer complex, polymerization creates a polymer network where the template molecules are anchored, and the final step involves removing the template to produce an MIP with cavities complementary to the template molecules. This review is the first paper to focus on advanced MIP-based IT-SPME, which integrates the selectivity of MIPs into efficient IT-SPME, and summarizes its recent developments and applications. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The three-dimensional imprinted polymeric network was synthesized via a bulk polymerization reaction in the presence of a flavonoid as a template. In this reaction, methacrylic acid (MAA) and acrylic acid (AA), tetrahydrofuran and trimethylolpropanetrimethacrylate, were used as functional monomers, porogen, and cross-linker, respectively. In this study, two kinds of molecularly imprinted polymers (MIPs) with different ratios of 1:8:40 and 1:20:80 (template: functional monomer: cross-linker) were synthesized and compared together. The related binding capacities were calculated as equal to 392.08 mg/g and 609.00 mg/g, respectively, by UV-spectrometer. The synthesized polymers have been evaluated via field emission scan electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller techniques. High selectivity and the proper specific surface area as equal to 167.00 m2/g in MIPs-based methacrylic acid (MIPs-MAA) and 434 m2/g in MIPs-based acrylic acid (MIPs-AA) comparatively to non-imprinted molecular polymers are the privileged characteristics in this research. The MIPs provided are a good candidate for the separation of flavonoids with the solid phase extraction method. [ABSTRACT FROM AUTHOR]

A novel magnetic molecular-imprinted polymer (MMIP) was used to selectively extract folic acid directly from real samples. Folic acid was used as template molecule, Fe3O4/SiO2-3-triethoxysilyl-propyl-acrylamide as functional monomer, azobisisobutyronitrile as initiation, ethylene glycol dimethacrylate as crosslinker agent, and acrylamide as the secondary monomer in a mixed ethanol-water solvent. The effect of different parameters on the extraction efficiency was studied, and the optimum conditions were established as follows: the concentrations of crosslinking and template were fixed at 0.05 and 0.06 g, absorption percentage was 96.5, pH was adjusted to 8, and extraction time was 8 h with a temperature of 25 °C. By examining the effect of pH, we tried to investigate the effect of the amide groups that present in MMIP and its intermolecular hydrogen interaction with folic acid. After optimising the effective parameters in polymer synthesis and adsorption rate, a magnetic imprinting dispersive solid-phase extraction method combined with fluorescence spectrophotometry at λem = 367 nm (MMIP-DSPE-FL) was constructed for sensitive determination of folic acid in tomato samples. The limit of quantification (LOQ) and limit of detection (LOD) values were 30.00 ± 0.01 μg L−1 and 10.00 ± 0.03 μg L−1, respectively, after the MMIP-DSPE preconcentration. Three tomato samples were analysed to give recoveries in the range of 80.2–81.6%, with relative standard deviation values below 0.6% (n = 3). The prepared MMIP-DSPE showed high selectivity toward folic acid, which could be used six times without changing adsorption capacity. The adsorption isotherm of the folic acid-imprinted polymer pursued the Langmuir model (RL = 0.029), and the kinetics model followed pseudo-first-order (R 2 = 0.9974). [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper demonstrates the synthesis and storage of molecular-imprinted polymers (MIP) at room temperature using bulk polymerization of atenolol (Ate), which is characterized by high sensitivity, low costs, and high stability. The research used 0.99:6:20 mmol ratios of template, monomer, and cross-linking agents for the polymerization in order to ensure an appropriate adsorption capacity. By making MIP for atenolol as Ate-MIP, which could be looked at with a UV-VIS spectrophotometer at 276 nm, Fourier- transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM), a functional monomer of allyl chloride with cross-linking ethylene glycol dimethyl acrylate was made. Mass spectrometric (MS) detection may use allyl chloride to determine atenolol levels in pharmaceutical preparations. The GC/MS methods developed in this study are accurate, sensitive, and precise and can be easily applied to (NOVATEN/India and ATENOIOI/U.K.) tablets in pharmaceutical preparation. The elution process was applied to the template (Ate) from the Ate-MIP, which developed cavities, caused by using porogenic solutions of methanol, chloroform, and acetic acid (70:20:10, respectively). The maximum adsorption capacity of Ate-MIP was 2.9957 µmol/g, and the ratio of template to monomer was 1:1 in adherence to the Langmuir isotherm model. A solid-phase extraction (SPE) syringe packed with molecular imprinted polymers (MIPs) was used to selectively separate and pre-concentrate Ate from aqueous solutions and estimations of atenolol. [ABSTRACT FROM AUTHOR]

This research investigates the usage of pipette tip micro solid phase extraction for the separation of 6-mercaptopurine of complicated matrices before its spectrophotometric detection. To overcome the non-selectivity of spectrophotometry, an ethylene glycol dimethacrylatebased molecularly imprinted polymer was prepared and applied as an adsorbent, which enabled selective and fast extraction of the analyte. To improve the transfer of the analyte to the adsorbent, a salting-out effect was employed by the addition of 300 mg of NaCl to the sample before performing microextraction. Variables affecting the microextraction of the protocol were investigated utilizing two ways one-factorat-a-time and response surface methodology, which showed good consistency with each other. Extraction parameters were optimized as pH of sample = 9.0, sample volume = 10 ml, amount of adsorbent = 2.0 mg, eluent = 250 µl of methanol:acetonitrile (1:5 v/v), and extraction and elution cycles of 10 and 12 times, respectively. The dynamic linear range of the protocol was 1.0-1000.0 µg l-1, with a limit of detection of 0.25 µg l-1. The method was compared with extraction by a non-imprinted polymer. The extraction efficiency of the analyte was obtained from 96.0% to 99.8%, by relative standard deviations better than 5.3%. The suggested technique was employed to determine 6-mercaptopurine in seawater and body fluid samples, and the results were validated by comparing them to a standard HPLC method. The whole analysis time, including microextraction, was about 25 min and to perform this method, the sole instrument required is a conventional spectrophotometer. [ABSTRACT FROM AUTHOR]

Two distinct spherical gold nanoparticles (AuNPs) were compared for the spectrophotometric determination of neomycin in saliva. The AuNPs were produced using AuCl3 and monobasic sodium citrate (in water bath at 100 °C) under magnetic stirring (AuNPs-citrate) and using HAuCl4 and NaBH4, at room-temperature under mechanical agitation in a commercial reactor (AuNPs-H). Both AuNPs were spherical with diameters of 7.7 nm (AuNPs-H) and 26.1 nm (AuNPs-citrate) and the maximum wavelength of the localized surface plasmon resonance (LSPR) bands were at 511 nm (AuNPs-H) and 529 nm (AuNPs-citrate). Equivalent spectral extinctions were found despite the fact the large difference in concentrations of AuNPs in dispersions: 4.2 × 10−9 mol L−1 for the AuNPs-H and 8.7 × 10−11 mol L−1 for the AuNPs-citrate. Both AuNPs interacted with aminoglycosides (AMG), affecting intensity of the LSPR band as the concentration of AMG increased. The response of the AuNPs-H was more sensitive toward AMG covering the following ranges: 0.6–600 µg L−1 (gentamicin), 7.3–550 µg L−1 (neomycin) and 14–520 µg L−1 (kanamycin). AuNPs-H optical response was more robust in function of the pH with AuNPs-citrate response only observed in acid solution, favoring electrostatic interaction with AMG. Catalytic activity of AuNPs-H, in reducing the 4-phenolate ion, presented a higher rate constant (4.3 × 10−3 s−1) and was used as analytical probe to determine neomycin in saliva after solid phase extraction with a commercially available AMG imprinted polymer enabling quantification to 0.36 μg of the analyte. [ABSTRACT FROM AUTHOR]

Stanozolol, a synthetic derivative of testosterone, is one of the common doping drugs among athletes and bodybuilders. It is metabolized to a large extent and metabolites are detected in urine for a longer duration than the parent compound. In this study, a novel dummy molecularly imprinted polymer (DMIP) is developed as a sorbent for solid-phase extraction of stanozolol metabolites from spiked human urine samples. The optimized DMIP is composed of stanozolol as the dummy template, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker in a ratio of 1:10:80. The extracted analytes were quantitively determined using a newly developed and validated ultrahigh-performance liquid chromatography tandem mass spectrometry method, where the limits of detection and quantitation were 0.91 and 1.81 ng mL−1, respectively, fulfilling the minimum required performance limit decided on by the World Anti-Doping Agency. The mean percentage extraction recoveries for 3'-hydroxystanozolol, 4β-hydroxystanozolol, and 16β-hydroxystanozolol are 97.80% ± 13.80, 83.16% ± 7.50, and 69.98% ± 2.02, respectively. As such, the developed DMISPE can serve as an efficient cost-effective tool for doping and regulatory agencies for simultaneous clean-up of the stanozolol metabolites prior to their quantification. [ABSTRACT FROM AUTHOR]

Ellagic acid (EA) is a natural polyphenol and possesses excellent in vivo bioactivity and antioxidant behaviors, which play an important role in the treatment of oxidative stress-related diseases, such as cancer. Additionally, EA is also known as a skin-whitening ingredient. The content of EA would determine its efficacy. Therefore, the accurate analysis of EA content can provide more information for the scientific consumption of EA-rich foods and cosmetics. Nevertheless, the analysis of EA in these samples is challenging due to the low concentration level and the presence of interfering components with high abundance. Molecularly imprinted polymers are highly efficient pretreatment materials in achieving specific recognition of target molecules. However, the traditional template molecule (EA) could not be absolutely removed. Hence, template leakage continues to occur during the sample preparation process, leading to a lack of accuracy in the quantification of EA in actual samples, particularly for trace analytes. In addition, another drawback of EA as an imprinting template is that EA possesses poor solubility and a high price. Gallic acid (GA), called dummy templates, was employed for the synthesis of MIPs as a solution to these challenges. The approach used in this study was boronate affinity-based oriented surface imprinting. The prepared dummy-imprinted nanoparticles exhibited several significant advantages, such as good specificity, high binding affinity ((4.89 ± 0.46) × 10−5 M), high binding capacity (6.56 ± 0.35 mg/g), fast kinetics (6 min), and low binding pH (pH 5.0) toward EA. The reproducibility of the dummy-imprinted nanoparticles was satisfactory. The dummy-imprinted nanoparticles could still be reused even after six adsorption–desorption cycles. In addition, the recoveries of the proposed method for EA at three spiked levels of analysis in strawberry and pineapple were 91.0–106.8% and 93.8–104.0%, respectively, which indicated the successful application to real samples. [ABSTRACT FROM AUTHOR]

In the past few decades, considerable scientific strides have been made in the subject of drug analysis in human biological samples. However, the risk caused by incorrect drug plasma levels in patients still remains an important concern. This review paper attempts to investigate the advances made over the last ten years in common sample preparation techniques (SPT) for biological samples based on solid sorbents, including solid-phase extraction (SPE) and solid-phase micro-extraction (SPME), and in particular in the field of molecularly imprinted polymers (MIPs), including non-stimuli-responsive and stimuli-responsive adsorbents. This class of materials is known as 'smart adsorbents', exhibiting tailored responses to various stimuli such as magnetic fields, pH, temperature, and light. Details are provided on how these advanced SPT are changing the landscape of modern drug analysis in their coupling with liquid chromatography-mass spectrometry (LC-MS) analytical techniques, a general term that includes high-performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography (UHPLC), as well as any variation of MS, such as tandem (MS/MS), multiple-stage (MSn), and high-resolution (HRMS) mass spectrometry. Some notes are also provided on coupling with less-performing techniques, such as high-performance liquid chromatography with ultraviolet (HPLC-UV) and diode array detection (HPLC-DAD) detection. Finally, we provide a general review of the difficulties and benefits of the proposed approaches and the future prospects of this research area. [ABSTRACT FROM AUTHOR]

Triazine pesticides can easily remain in the environment and food, causing serious harm to organisms. Developing a pretreatment technology with strong purification and enrichment capabilities is of great significance for the detection of triazine. In this paper, magnetic dual-template nanomolecular imprinted polymers (MMIPs) were synthesized using silica-modified Fe3O4 magnetic shell nanoparticles as carriers, methacrylic acid (MAA) as a functional monomer, and cyromazine and melamine as template molecules. This material was characterized by transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The adsorption experiments were carried out and the results showed that the MMIPs had the chemical properties of surface molecular imprinting. The binding constants of MMIPs were 26.95 mg/L and 657.89 mg/L, and their maximum apparent binding capacity was 2.02 mg/g and 8.59 mg/g, respectively. The prepared MMIPs were used as adsorbents for dispersive solid phase extraction, and high-performance liquid chromatography analysis was coupled to determine triazine pesticides from three samples. The recovery of this method was between 84.8% and 109.5% and the limits of detection were between 0.01–0.03 µg/L. This method greatly shortens the sample pretreatment time and achieves the purpose of rapid pretreatment. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), known for its endocrine-disrupting properties and potential to leach into food products, has led to significant food safety concerns. Therefore, the development of sensitive and selective BPA rapid detection methods is crucial. In this study, molecularly imprinted solid-phase extraction coupled to a colorimetric method was adopted for the smartphone-based determination of BPA. The molecularly imprinted polymer (MIP) was prepared via photopolymerization and used as a selective adsorbent material for SPE columns. The solid-phase extraction (SPE) columns with multiple cycles significantly reduced the extraction time to only 30 min. The developed method demonstrates useful sensitivity for BPA (LOD = 30 ppb). Furthermore, BPA migration from plastic packaging was evaluated under different storage conditions, revealing that microwave treatment for 5 min led to BPA release from polycarbonate packaging in juice and basic solutions. The MIP selective extraction/clean-up and smartphone-based optical sensor were successfully applied to BPA standard solutions and complex food samples (e.g., juice and tap water), resulting in reproducible and selective BPA determination (RSD ≤ 6%, n = 3). This rapid and cost-effective method of producing MIPs for BPA offers a promising solution for fast and low-cost sensing for on-site fresh food analysis. [ABSTRACT FROM AUTHOR]

The antiretroviral drugs (ARVDs) have been reported to be among the emerging water pollutants as a results attention is being paid on their analysis. This work therefore explored for the first time the multi-template MIP for the selective removal of selected ARVDs (abacavir, efavirenz and nevirapine) in wastewater, river water and tap water. The adsorption studies of a multi-template MIP were conducted by determining the effect of an increase in ARVDs concentration in solution and the effect of an increase in contact time between the sorbent and the ARVDs. High adsorption efficiencies were observed for abacavir, efavirenz and nevirapine analytes within 5 min and the maximum adsorption efficiency was observed at 60 min ranging from 94.76 to 96.93%. Adsorption kinetics showed that pseudo-second rate order was the best fitting model, while adsorption isotherms indicated that the Freundlich isotherm (R2 = 0.94–0.98) best described the adsorption mechanism of ARVDs onto the MIPs. These results indicated that the electrostatic attractions influenced the multilayer coverage and chemisorption process. Selectivity studies conducted in the presence of competitors gave the recoveries between 92 and 98% for the target analytes, while they were 63–79% for competitors indicating good selectivity and strong affinity of the polymer towards the target analytes. Reusability studies showed that the MIP can be reused for up to 8 cycles with recoveries above 92% for all target ARVDs. The application of the MIP-DSPE method to wastewater, river and tap water samples gave concentrations of 28.75–178.02, 1.95–13.15 and 2.17–6.27 µg L−1, respectively. These results indicate the potential unplanned consumption of ARVDs upon drinking contaminated water which could result to their resistance by the human body. Therefore, their continuous monitoring as well as investigation of their removal strategies is of paramount importance. [ABSTRACT FROM AUTHOR]

In this research, a molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization using oxazepam (OZ) as a template molecule and was subsequently applied as a selective sorbent for the extraction of diazepam (DZP) and its metabolites in urine samples using an SPE cartridge. OZ, temazepam (TZ), nordiazepam (NZ) and DZP were analyzed in the final extracts by high-performance liquid chromatography with diode array detection (HPLC-DAD). The SPE extraction steps were optimized, and the evaluation of an imprinting factor was carried out. The selectivity of the method for OZ versus structurally related benzodiazepines (BZDs), such as bromazepam (BRZ), tetrazepam (TTZ) and halazepam (HZ), was investigated. Under the optimum conditions, the proposed methodology provided good linearity in the range of 10–1500 ng/mL, with limit of detection values between 13.5 and 21.1 ng/mL and recovery levels for DZP and its metabolites from 89.0 to 93.9% (RSD ≤ 8%) at a concentration level of 1000 ng/mL. The proposed method exhibited good selectivity, precision and accuracy and was applied to the analysis of urine samples from a real case of DZP intake. [ABSTRACT FROM AUTHOR]

In this study, adsorbents based on molecularly imprinted polymers (MIPs) in two solid-phase extraction application forms, pipette tip and magnetic extraction, were used for the selective extraction of coumarins. The pipette-tip solid-phase extraction reduced solvent volumes; the magnetic MIP extraction was simple and effective for phase separation. Parameters affecting extraction, such as the amount of adsorbent, type of washing solvent, volume of the elution solvent, and extraction times for magnetic extraction, were optimized. The MIP-based adsorbents displayed high selectivity and extraction efficiency, resulting in recoveries ranging from 70.3 to 102.0% (RSD % less than 5.5%) for five coumarins under study, 6,7-dihydroxycoumarin-6-β-D-glucoside, coumarin, 7-methoxycoumarin, 6-methylcoumarin, and dicoumarol. The extracts were analyzed by high-performance liquid chromatography with diode array (DAD) and fluorescence (FLD) detectors, reaching limits of quantification of 0.5 and 0.9 µg·mL−1 for coumarin and dicoumarol detected by DAD and 0.001–0.012 µg·mL−1 for the other prohibited simple coumarins when used as a fragrance (detected by FLD). The proposed method was validated and its applicability was shown for the analysis of cosmetic samples like shower gel and perfume. [ABSTRACT FROM AUTHOR]

A novel silica fabricated allyloxy ethanol based imprinted polymer is synthesised with surface area of 333 m2 g−1 and average pore size of 6.5 nm by an environment friendly one pot surface imprinting process. It was employed for the selective solid‐phase extraction (SPE) of trace Ni(II) in real samples prior to FAAS determination. The factor settings produced via central composite design in response surface methodology (RSM) (pH: 3.6; initial concentration; 800 mg L−1 and time; 15 minute) provide adsorption capacity of 176 mg g−1. Artificial neural network model employed on the RSM data, provided better predictability. Sips isotherm model and BSf kinetic model describes best the sorption phenomena of the homogenous binding terrain. The developed SPE‐coupled FAAS method demonstrate a detection limit of 1.62 μg L−1, quantification limit of 4.17 μg L−1, and Linear dynamic range of 20–8000 μg L−1. It was successfully applied to determine nickel in food (Spinach, Radish, Green tea infusion, Black tea infusion, Coffee, Soya milk, Chocolate Soya milk, Tobacco) and wastewater samples (>99 % removal). For five replicate determinations, the method's relative standard deviation was 2.3 %. The method was validated by analysing two certified reference materials, and the outcomes were well‐congruent with standard values. For the synthesised polymer Ni(II) exhibits higher distribution ratio than other competing ions (Cu(II), Pb(II), Cd(II), and Zn(II)) with the imprinting factor; β values of 5.73, 4.98, 6.80, and 5.04 respectively. The reusability experiments revealed that APS@Ni‐IIP retains a strong adsorption efficacy even after 15 cycles and after its exhaustion it was employed as catalyst for reducing permanganate ions, further reducing pollution. The rigid structure of mesoporous silica contributes to its acid resilience and reusability, which can lead to a relative increase in polymer performance in absorption rate and selectivity. Apart from the novelty in the synthesis, thorough examination of the method and material selectivity (in binary, ternary and multielement system), multi fold applications of determination, removal of Ni(II) and reduction of permanganate ions, makes APS@Ni‐IIP a promising candidate for environmental remediation. [ABSTRACT FROM AUTHOR]

Low levels of α‐mangostin (AM) in biological fluids require adequate sample preparation to be analyzed. Molecularly imprinted polymers can serve as sorbents in solid phase extraction, enabling concentration and extraction of α‐mangostin from complex matrices, such as biological fluids. To date, there are no molecular imprinted polymers for the analysis of α‐mangostin in biological fluids. In this study, AM molecular imprinted polymer (MIP) was designed using molecular modeling, molecular dynamic simulations, and prepared by bulk polymerization and suspension polymerization methods. The geometry optimization results showed that acrylamide (AAM) monomer forms the most stable complex with AM at the pre‐polymerization with the most negative Gibbs free energy (ΔG) of −6.91818 Kcal/mol. Radial distribution function (RDF) in molecular dynamics simulation of AM:AAM:ethylene glycol dimethacrylate (EGDMA) with mol ratio 1:4:20 shows the complex with the best composition through the formation of four stable hydrogen bonds. Based on the experimental results, molecularly imprinted polymers in suspension exhibit better characteristics, selectivity, and adsorption capacity than in bulk. The suspension polymerization method showed a high recovery (85.88% ± 2.5), which was higher than C18 SPE cartridge (24.19% ± 1.47). Hence, it can be concluded that the MIPs from MD simulations were accessible and could be used in practice, such as in the separation and detection of AM in blood serum. [ABSTRACT FROM AUTHOR]

This study describes methodologies for extracting and isolating bergenin, a C-glucoside of 4-O-methylgallic acid found in some plants and it presents various in vitro and in vivo biological activities. Bergenin was previously obtained from the Pelthophorum dubim (Fabaceae) roots with a good yield. Conventional chromatographic procedures of the CHCl3 soluble fraction of the MeOH extract gave 3.62% of this glucoside. An HPLC/DAD method was also developed and validated for bergenin and its precursor, gallic acid quantifications. Microwave extractions with different solvents were tested to optimize the extraction of bergenin, varying the temperature and time. MAE (Microwave Assisted Extraction) was more efficient than conventional extraction procedures, giving a higher yield of bergenin per root mass (0.45% vs. 0.0839%). Molecularly imprinted polymer (MIP) and non-imprinted polymer (NIP) based on bergenin as the template molecule, methacrylic acid, and ethylene glycol dimethacrylate were synthesized and characterized by FTIR and SEM (Scanning Electron Microscopy). Bergenin adsorption experiments using MIP and NIP followed by molecular imprinted solid phase extraction (MISPE) showed that MIP had a higher selectivity for bergenin than NIP. A dendrochronological study using the proposed method for detection and quantification of gallic acid and bergenin in five P. dubium growth rings of a 31-year-old heartwood and in the phelloderm and barks indicated that bergenin was more abundant in the 11–14th growth rings of the heartwood and decreased from the heartwood to the barks. [ABSTRACT FROM AUTHOR]

An L‐tetrahydropalmatine (L‐THP) imprinted silica gel polymer functionalized with aminated groups was prepared with surface imprinting technique by using L‐THP as template, grafted silica gel as support, methacrylic acid as functional monomer and ethylene glycol dimethyl acrylate as cross‐linker by solution polymerization. The optimum ratio of template, functional monomer, and cross‐linker were found to be 1:4:20 and the conditions of synthesis were 50°C for 18 h. The surface imprinting silica gel polymer of L‐THP was used as a sorbent for L‐THP adsorption and showed better adsorption capacity of L‐THP than that of non‐imprinted polymers. Then the surface imprinting silica gel polymer of L‐THP was filled into the cartridges as the adsorbents of solid‐phase extraction, and the mean recoveries of L‐THP and D‐tetrahydropalmatine were 70.1% and 17.1% with 2.8% and 3.0% of relative standard deviation, respectively. [ABSTRACT FROM AUTHOR]

Mycotoxins are toxic metabolites of molds which can contaminate food and beverages. Because of their acute and chronic toxicity, they can have harmful effects when ingested or inhaled, posing severe risks to human health. Contemporary analytical methods have the sensitivity required for contamination detection and quantification, but the direct application of these methods on real samples is not straightforward because of matrix complexity, and clean-up and preconcentration steps are needed, more and more requiring the application of highly selective solid-phase extraction materials. Molecularly imprinted polymers (MIPs) are artificial receptors mimicking the natural antibodies that are increasingly being used as a solid phase in extraction methods where selectivity towards target analytes is mandatory. In this review, the state-of-the-art about molecularly imprinted polymers as solid-phase extraction materials in mycotoxin contamination analysis will be discussed, with particular attention paid to the use of mimic molecules in the synthesis of mycotoxin-imprinted materials, to the application of these materials to food real samples, and to the development of advanced extraction methods involving molecular imprinting technology. [ABSTRACT FROM AUTHOR]

This study introduces a cost‐effective, automated ultra‐high‐performance liquid chromatography–tandem mass spectrometry method for the detection of 14 β‐agonists in pork using a novel solid‐phase microextraction probe composed of polyacrylonitrile and molecularly imprinted polymer. Integrated into an automated extraction device, the probe optimizes extraction prior to analysis while reducing expenses and time compared to traditional solid‐phase extraction procedures. The method validation followed the Chinese National Standard (GB/T 27404‐2008) and examined limits of detection, limits of quantification, matrix effects, linearity, intraday, and interday precision. Average recovery rates ranged from 71.6% to 82.2%, with relative standard deviations less than 15%. Limits of detection and limits of quantification ranged from 0.09 to 0.39 and 0.27 to 0.99 μg/kg, respectively. The new method identified positive samples more accurately than the current National Standard GB/T 31658.22‐2022 and demonstrated its potential for routine assessment and regulatory compliance in the detection of β‐agonists in pork. [ABSTRACT FROM AUTHOR]

This work describes the development of an analytical methodology to determine toxic fenpyroximate in surface water using molecularly imprinted polymers (MIPs) as the extraction and pre-concentration material, followed by high performance liquid chromatography. A new molecularly imprinted polymer, prepared following a non-covalent approach, was synthesised using toxic fenpyroximate as the template molecule, methacrylic acid as a functional monomer, and ethylene glycol dimethacrylate as a cross-linker. A method for the determination of traces of toxic fenpyroximate was developed using this polymer as the enrichment sorbent coupled with high performance liquid chromatography focusing on surface water samples. The calibration curve was linear in the range of 0.1 to 1.0 µg L−1. The standard deviation is 2.9%, and the detection limit of the method is 0.2 µg L−1 and r2 = 0.9869. The observed outcomes confirmed the suitability recovery and a very low detection limit for measuring toxic fenpyroximate. It was demonstrated that the proposed MI-SPE-HPLC method could be applied for direct determination of toxic fenpyroximate in surface water. The observed outcomes confirmed the suitability of the artificial neural network model as a tool for MSE (mean square error) of fenpyroximate on (MSEANN = 0.41, MSEFL = 0.36 and MSEANFIS = 0.23) selectivity and permeability. It was demonstrated that the proposed MI-SPE-HPLC method could be applied for direct determination of toxic fenpyroximate in surface water. [ABSTRACT FROM AUTHOR]

This review presents an outline of the application of the most popular sorbent-based methods in food analysis. Solid-phase extraction (SPE) is discussed based on the analyses of lipids, mycotoxins, pesticide residues, processing contaminants and flavor compounds, whereas solid-phase microextraction (SPME) is discussed having volatile and flavor compounds but also processing contaminants in mind. Apart from these two most popular methods, other techniques, such as stir bar sorptive extraction (SBSE), molecularly imprinted polymers (MIPs), high-capacity sorbent extraction (HCSE), and needle-trap devices (NTD), are outlined. Additionally, novel forms of sorbent-based extraction methods such as thin-film solid-phase microextraction (TF-SPME) are presented. The utility and challenges related to these techniques are discussed in this review. Finally, the directions and need for future studies are addressed. [ABSTRACT FROM AUTHOR]

In this work, we present a fast, simple and selective method for the extraction/preconcentration and determination of five opium alkaloids. This method is based on the combination of dispersive solid phase extraction with magnetic molecularly imprinted polymers (MMIP) and determination via high performance liquid chromatography. The surface modified Fe3O4 nanoparticles were synthesised in-situ, from a co-precipitation method by addition of a mixture of the methacrylic acid and ammonia to a mixture of Fe2+/Fe3+ under nitrogen atmosphere. MMIP was prepared from surface modified nanoparticles in the presence of ethylene glycol dimethyl acrylate as cross-linker and azobisisobutyronitrile as initiator and template molecule under reflux in acetonitrile. MMIPs for five natural occurring opium alkaloids, including morphine (MO), codeine (CO), thebaine (TE), noscapine (NO) and papaverine (PA) were prepared in the same manner. Structural characterisation and elucidation of both synthesised nanoprticles were performed by Fourier transform-infrared spectroscopy, scanning electron microscopy. X-ray diffraction and vibrating sample magnetometry. A precise chromatographic method was developed and coupled with extraction with MMIP nanoparticles for simultaneous preconcentration and determination of above-mentioned alkaloids in underground water samples. The limit of detection obtained 0.007, 0.007, 0.004, 0.003, 0.003 mg L−1 for MO, CO, TE, NO and PA, respectively and recoveries were about 97–102%. Linear dynamic range and relative standard deviation were 0.03–100 mg L−1 and less than 1.5% for each analyte. [ABSTRACT FROM AUTHOR]

The escalating issue of water pollution has become a worldwide issue that has captured the attention of numerous scientists. Molecularly imprinted polymers (MIPs) have emerged as adaptable materials with exceptional attributes, including easy synthesis, low cost, remarkable durability, long life, and accessibility. These attributes have motivated researchers to develop novel materials based on MIPs to tackle hazardous contaminants in environmental matrices. The purpose of this paper was to conduct a bibliometric analysis on MIPs' publications, in order to shed light on the developments and focus points of the field. The selected publications were obtained from Scopus database and subjected to a filtering process, resulting in 11,131 relevant publications. The analysis revealed that the leading publication source (journal) is Biosensors and Bioelectronics; the mostly employed keywords are solid-phase extraction, electrochemical sensor, and molecular recognition; and the top contributing countries are China, Iran, and the USA. The Latent Dirichlet Allocation (LDA) algorithm was used for extracting thematic axes from the textual content of the publications. The results of the LDA model showcase that the topic of synthesis and performance of MIPs for environmental applications can be considered as the most dominant topic with a share value of 72.71%. From the analysis, it can be concluded that MIPs are a cross-disciplinary research field. [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer with a specific selectivity for patulin was successfully synthesized. The molecularly imprinted material was prepared using the two functional monomers dopamine and melamine and formaldehyde as the cross-linker. The resulting material possessed a large number of hydrophilic groups, such as hydroxyls, imino groups, and ether linkages. For the first time, uric acid was used as a dummy template for its structural similarity to patulin. Comprehensive characterization and detailed studies of the adsorption process were carried out via adsorption isotherms, while the rate-limiting steps were investigated using adsorption kinetics. Separation, determination, and quantification of patulin were achieved by ultra-high performance liquid chromatography coupled with both photodiode array detection and tandem mass spectrometry. The latter was applied to patulin confirmation in the analysis of real samples. The methodology was validated in 20 apple juice samples. The results showed that the developed hydrophilic molecularly imprinted polymer had high selectivity and specific adsorption towards patulin, with mean recoveries ranging between 85 and 90% and a relative standard deviation lower than 15%. The developed molecularly imprinted polymer exhibited good linearity in the range 1–100 ng mL−1 with coefficient of determination (R2) > 0.99. The limit of detection was 0.5 ng mL−1, and the limit of quantification was 1 ng g−1. The developed method showed a good purification capacity for apple juices due to its hydrophilic nature and the polar interactions established with the target analyte. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Within the world of natural food supplements, organic extracts deriving from young plant meristematic tissue (bud-derivatives) are becoming attractive, thanks to their richness in bioactive molecules. This natural source is scarce, but every year, tons of plant material, including buds, come from city pruning. If this sustainable source is rather promising from a circular economy point of view, the safety of the obtained supplements must be assessed. In fact, anthropic microcontaminants, such as polycyclic aromatic hydrocarbons (PAHs), could adsorb onto the urban buds, leading to a possible contamination of the bud-derivatives. In this study, we developed a magnetic dispersive solid phase extraction (m-dSPE) based on molecularly imprinted microparticles, combined with GC-MS, to quantify the 16 priority PAHs in such extracts. The D-optimal experimental design was implemented to maximize analytes' recovery with the smallest set of experiments. The optimized method was characterized by great selectivity thanks to the molecular imprinted polymer and ease of use provided by m-dSPE. Moreover, it complies with green principles, thanks to the minimum consumption of organic solvent (1.5 mL of acetone per sample). The recoveries ranged from 76 to 100% and procedural precision was below 10% for most PAHs. Despite the matrix complexity, low quantification limits (0.7–12.6 μg kg−1) were reached. This guaranteed the PAHs' quantitation at levels below those indicated as safe by a European Community regulation on food supplements. None of the analyzed samples, coming from different anthropically impacted areas, showed concerning PAHs levels. [ABSTRACT FROM AUTHOR]

The illegal addition of progesterone to cosmetics could cause serious adverse reactions and pose a serious threat to human health. In this work, a simple, fast and sensitive method was developed by combining molecularly imprinted solid-phase extraction and high-performance liquid chromatography (MISPE–HPLC) for the selective determination of progesterone in cosmetics. Chitosan-modified silica is used as the carrier to provide binding sites for the effective conjugation of the target. The obtained molecularly imprinted polymers exhibited excellent adsorption capacity (36.2 mg·g−1), good selectivity and fast mass transfer rate for progesterone. Meanwhile, the prepared MISPE column could eliminate the interference of co-existing substances. Combined MISPE with HPLC, a selective and effective method for detecting progesterone in different cosmetics was achieved. Under the optimum conditions, the established MISPE–HPLC method was successfully used for the detection of progesterone in real samples. The linear range of this method was 1 to 200 μg·mL−1 with a limit of detection of 0.016 μg·mL−1. Therefore, this method could be used for the selective and effective detection of progesterone in different cosmetic samples with complex substrates. We provided an alternative method for the detection of illegal additions in cosmetics. [ABSTRACT FROM AUTHOR]

This paper describes a new methodology for carrying out quantitative extraction of cloxacillin from drinking and river water samples using a molecularly imprinted polymer (MIP) as a selective sorbent for solid-phase extraction (MISPE). Several polymers were synthesized via thermal polymerization using cloxacillin as a template, methacrylic acid (MAA) as a functional monomer, ethyleneglycoldimethacrylate (EGDMA) as a cross-linker and different solvents as porogens. Binding characteristics of the adequate molecularly imprinted and non-imprinted (NIP) polymers were evaluated via batch adsorption assays following the Langmuir and Freundlich isotherms and Scatchard assays. The parameters related to the extraction approach were studied to select the most appropriate polymer for cloxacillin determination. Using the optimized MIP as the SPE sorbent, a simple sample treatment methodology was combined with high-performance liquid chromatography (HPLC) to analyze cloxacillin residues in drinking and river water. Under the optimum experimental conditions, the MISPE methodology was validated using spiked samples. The linearity for cloxacillin was assessed within the limits of 0.05–1.5 µg L−1 and the recovery percentage was higher than 98% (RSD < 4%). The limits of detection and limits of quantification were 0.29 and 0.37 µg L−1 and 0.8 and 0.98 µg L−1 for drinking and river water, respectively. The selectivity of MIP against other ß-lactam antibiotics with similar structures (oxacillin, cefazoline, amoxicillin and penicillin V) was studied, obtaining a good recovery higher than 85% for all except cefazoline. The proposed MISPE-HPLC methodology was successfully applied for the detection of cloxacillin in drinking water from Canal de Isabel II (Madrid) and river water from the Manzanares River (Madrid). [ABSTRACT FROM AUTHOR]

Background: Clenbuterol (CLB) is approved as a veterinary drug because of its tracheal smooth muscle and uterine relaxant effects. However, if improperly administered for the purpose of fattening livestock, CLB can remain in the organs, which may pose a health hazard to humans. Objective: We aimed to examine the combination of molecularly imprinted polymer (MIP) and solid-phase dispersive extraction (SPDE) as a pretreatment method for swine liver and kidney, which contain more coexisting impurities than muscle tissue, and attempted to construct an analytical method using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methods: Swine livers and kidneys were homogenized and extracted using liquid-liquid partitioning with an ethyl acetate-n-hexane (1 þ 1) mixture, followed by SPDE using an MIP gel, and measured using LC-MS/MS. For LC-MS/MS, either an absolute calibration method or isotope dilution mass spectrometry (IDMS) was used. For method validation, a recovery test (additive concentrations: 0.05 and 0.5 ng/g) was conducted, and the data were analyzed using one-way analysis of variance (ANOVA). Results: The recoveries (trueness), repeatability, and intermediate precision obtained using absolute calibration were similar to those obtained using IDMS. Conclusion: Using MIP-SPDE as a pretreatment method for CLB in swine liver and kidney samples yielded comparable results for absolute calibration and IDMS in LC-MS/MS analysis. Highlights: MIP-SPDE can be used as a pretreatment method to analyze CLB in swine organs with high accuracy. [ABSTRACT FROM AUTHOR]

Background: Solid phase extraction (SPE) techniques, based on computationally designed magnetic-based multi-targeting molecular imprinted polymer (MT-MIP), combined with UV spectrophotometric approaches provide advantages in the examination of counterfeit samples. Objective: The current work describes an innovative and sustainable methodology for the simultaneous determination of tadalafil (TAD) and dapoxetine hydrochloride (DAP) in aphrodisiac counterfeit products (honey and instant coffee) utilizing SPE exploiting MT-MIP. Additionally, an innovative UV spectrophotometric method capable of resolving TAD in its pharmaceutical binary mixtures with DAP was developed. A novel computational approach was implemented to tailor the synthesis and design of the MT-MIP particles. Methods: We applied a newly developed UV spectrophotometric method which was based on a Fourier self-deconvolution (FSD) method coupled with the isoabsorptive point for determination of TAD and DAP in pharmaceutical dosage form. We also applied an SPE process based on MT-MIP designed particles, assisting in the analysis of both drugs in counterfeit food samples. The SPE process and the UV spectroscopic methodology were assessed regarding their greenness using the pioneering green analytical procedure index (GAPI), analytical greeness including sample preparation (AGREEprep) and AGREE tools. The synthesized MT-MIP particles were characterized by scanning electron microscopy and energy-dispersive x-ray spectroscopy. Results: The suggested spectrophotometric methods revealed a wide linear concentration range of 2-50 mg/mL with lower LODs in the range of 0.604-0.994 mg/mL. Additionally, the suggested method demonstrated the utmost sensitivity and eco-friendliness for their target in its mixed dosage form and counterfeit food products. Conclusion: The SPE process and the developed analytical UV spectroscopic methodology were validated as per the ICH guidelines, and were found to be suitable for overseeing some counterfeiting activities in commercially available honey and instant coffee aphrodisiac products. Highlights: An SPE method based on MT-MIP magnetic-based polymer and a UV spectroscopic method were successfully developed for analysis of TAD and DAP in different matrices. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, the synthesis of thin-layer, pH-sensitive molecularly imprinted membrane using methacrylic acid and maleic acid as functional monomers, ethylene glycol dimethacrylate as cross-linker, 2,2′-azobisisobutyronitrile as initiator, poly (vinylidene fluoride) as porous membrane, and celecoxib as a target molecule have been reported. Different technique analyses characterized the membrane product. A novel molecularly imprinted membrane-solid phase extraction method was used for the extraction of celecoxib and concentrating it prior to be analyzed in the human plasma and urine matrix. High-performance liquid chromatography with ultraviolet detection was used and validated for the analysis of celecoxib which was extracted from biological fluids. The molecularly imprinted membrane showed selective performance for the template, and extraction recoveries of the drug by the membrane from human plasma and urine samples were between 96.2 and 97.3%. The obtained results showed that the detection and quantification limits of the drug were 0.12 and 0.40 ng mL−1, respectively. The adsorption capacity of 4.95 mg g−1 was obtained from the fitting by the Langmuir model. The molecularly imprinted membrane can be easily regenerated eight times with sustained efficiency. Therefore, the developed method can be a good candidate for the separation and detection of celecoxib in biological samples. [ABSTRACT FROM AUTHOR]

A kind of hydroxycamptothecin (HCPT) hybrid molecularly imprinted polymer (AT/MA-HMIPs) with high selectivity and hard silicon skeleton was successfully prepared based on double hybrid monomers. The relationship between templates and functional monomers was studied through computer molecular simulation and experiments. Three single-monomer molecularly imprinted polymers were prepared as controls. The Langmuir isotherm and pseudo-second-order kinetic models were found to fit well with the adsorption results. The maximum adsorption capacity was 18.79 mg/g, and equilibrium was reached within 20 min. Moreover, it shows excellent selectivity (imprinting factor is 10.73) and good recoverability (after 10 adsorption-desorption cycles, the adsorption capacity only decreases by 7.75%) for HCPT. The purity of HCPT can reach 80.86% after being put into a solid phase extraction column and used in an actual sample, and the yield was 61.43%. This study lays the fundament for the development of excellent HCPT molecularly imprinted composites. [ABSTRACT FROM AUTHOR]

In this study, a novel technique is introduced that involves the combination of an ion-imprinted polymer and solid-phase extraction to selectively adsorb lithium ions from reverse osmosis brine. In the process of synthesizing ion-imprinted polymers, phthalocyanine acrylate acted as the functional monomer responsible for lithium chelation. The structural and morphological characteristics of the molecularly imprinted polymers and non-imprinted polymers were assessed using Fourier transform infrared spectroscopy and scanning electron microscopy. The adsorption data for Li on an ion-imprinted polymer showed an excellent fit to the Langmuir isotherm, with a maximum adsorption capacity (Qm) of 3.2 mg·g−1. Comprehensive chemical analyses revealed a significant Li concentration with a higher value of 45.36 mg/L. Through the implementation of a central composite design approach, the adsorption and desorption procedures were systematically optimized by varying the pH, temperature, sorbent mass, and elution volume. This systematic approach allowed the identification of the most efficient operating conditions for extracting lithium from seawater reverse osmosis brine using ion-imprinted polymer–solid-phase extraction. The optimum operating conditions for the highest efficiency of adsorbing Li+ were determined to be a pH of 8.49 and a temperature of 45.5 °C. The efficiency of ion-imprinted polymer regeneration was evaluated through a cycle of the adsorption–desorption process, which resulted in Li recoveries of up to 80%. The recovery of Li from the spiked brine sample obtained from the desalination plant reverse osmosis waste through the ion-imprinted polymer ranged from 62.8% to 71.53%. [ABSTRACT FROM AUTHOR]

Carisoprodol (CSP) is one of the most common antispasmodic drugs used to reduce muscle spasms; however, it is also abused due to its mind-altering effects. Consequently, its abuse leads to the major concern of increased risk of fatal road accidents due to impaired driving. Therefore, it is crucial but challenging for forensic toxicologists to effectively extract and detect CSP in complex biological matrices. Hence, herein, a novel analytical technique based on a molecularly imprinted polymer (MIP) coupled with dispersive solid-phase extraction (MIP-DSPE) was developed for the simple, rapid, selective extraction and analysis of CSP by applying gas chromatography-mass spectrometry (GC-MS) from pharmaceutical and biological samples such as urine and blood. MIP was successfully synthesized via bulk polymerisation utilizing CSP as the template, methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinker, and azobisisobutyronitrile (AIBN) and acetonitrile as an initiator and porogen, respectively. Further, the as-synthesized polymer was characterized via field emission-scanning electron microscopy (FE-SEM) and Fourier-transform infrared spectroscopy (FTIR). An equilibrium adsorption experiment was performed to determine the binding affinity of the synthesized polymer. The different parameters affecting the efficiency of MIP-DSPE were optimized for the selective estimation of CSP in urine, blood, and pharmaceutical samples. The developed method exhibited reasonable linearity for the calibration range of 0.1–10 μg mL−1 together with correlation coefficients (R2) of more than 0.9993, 0.9993, and 0.9996 for urine, blood, and pharmaceutical samples, respectively. Under the optimized conditions, the percentage recoveries of CSP from urine, blood, and pharmaceutical samples were in the range of 83.9–113.2%. The limit of detection (LOD) and limit of quantification (LOQ) for urine, blood, and pharmaceutical samples were estimated to be 0.0052, 0.0076, and 0.0050 μg mL−1 and 0.0171, 0.0250, and 0.0165 μg mL−1, respectively. Moreover, the intra-day and inter-day precisions (n = 5) were under 7% and 11%, respectively. In addition, the greenness of the proposed technique was assessed employing the ComplexGAPI tool. [ABSTRACT FROM AUTHOR]

Molecularly imprinted membranes (MIMs), the incorporation of a given target molecule into a membrane, are generally used for separating and purifying the effective constituents of various natural products. They have been in use since 1990. The application of MIMs has been studied in many fields, including separation, medicine analysis, solid-phase extraction, and so on, and selective separation is still an active area of research. In MIM separation, two important membrane performances, flux and permselectivities, show a trade-off relationship. The enhancement not only of permselectivity, but also of flux poses a challenging task for membranologists. The present review first describes the recent development of MIMs, as well as various preparation methods, showing the features and applications of MIMs prepared with these different methods. Next, the review focuses on the relationship between flux and permselectivities, providing a detailed analysis of the selective transport mechanisms. According to the majority of the studies in the field, the paramount factors for resolving the trade-off relationship between the permselectivity and the flux in MIMs are the presence of effective high-density recognition sites and a high degree of matching between these sites and the imprinted cavity. Beyond the recognition sites, the membrane structure and pore-size distribution in the final imprinted membrane collectively determine the selective transport mechanism of MIM. Furthermore, it also pointed out that the important parameters of regeneration and antifouling performance have an essential role in MIMs for practical applications. This review subsequently highlights the emerging forms of MIM, including molecularly imprinted nanofiber membranes, new phase-inversion MIMs, and metal–organic-framework-material-based MIMs, as well as the construction of high-density recognition sites for further enhancing the permselectivity/flux. Finally, a discussion of the future of MIMs regarding breakthroughs in solving the flux–permselectivity trade-off is offered. It is believed that there will be greater advancements regarding selective separation using MIMs in the future. [ABSTRACT FROM AUTHOR]

Terbutylazine (TER)—simetryn (SIE) molecularly imprinted polymers (TER-SIE-MIPs) were prepared by precipitation polymerization with TER and SIE as double template molecules, acrylic acid (AA) as the functional monomer, and acetonitrile as the porogen. A method of molecularly imprinted solid-phase extraction combined with high performance liquid chromatography (MISPE-HPLC) was developed for the determination of four triazine herbicide residues in tobacco leaves. The optimal functional monomer was firstly selected, then the optimal binding ratio between template and monomer was determined by computer simulation algorithm. The adsorption performance of the MIPs to double template molecules was investigated by adsorption experiments. It was found that the MIPs had two types of affinity sites, and good specific adsorption capacity for TER and SIE and their structural analogs. Then TER-SIE-MIPs was used as a solid phase extraction filler to prepare a TER-SIE-MISPE column for pretreatment of spiked tobacco leaves, and the pretreatment liquid was analyzed by HPLC, and the results showed that TER-SIE-MISPE had better enrichment effect on terbutylazine, simetryn, terbumeton and prometryn. The average recoveries of the four triazine herbicides were between 80.95 and 103.15%, and the relative standard deviations (RSD) were 1.82 ~ 2.57% (n = 3), the method can meet the requirements of simultaneous determination of terbutylazine, simetryn, terbumeton and prometryn triazine herbicide residues in tobacco leaves. [ABSTRACT FROM AUTHOR]

Styrene, a chemical widely used in various industries, undergoes metabolic breakdown in the human body, resulting in the production of phenylglyoxylic acid (PGA). A novel molecularly imprinted polymer (MIP) was synthesised for selective extraction and enrichment of PGA in urine samples prior to high-performance liquid chromatography. The MIP employed in this research was a 4-vinylpyridine molecularly imprinted polymer (4-VPMIP) prepared via mass polymerisation using a noncovalent method. The structural and morphological characteristics of the molecularly imprinted polymers (MIPs) and non-imprinted polymers (NIPs) were evaluated using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The efficiency of the molecularly imprinted solid-phase extraction (MISPE) process was optimised by investigating critical variables such as sample pH, sorbent mass, sample flow rate, and volume of the elution solvent. A central composite design (CCD) within the response surface methodology was utilised to develop separate models for the adsorption and desorption steps. Analysis of variance (ANOVA) confirmed the excellent fit of the experimental data to the proposed response models. Under the optimised conditions, the molecularly imprinted polymers exhibited a higher degree of selectivity and affinity for PGA, with a relative selectivity coefficient (α) of 2.79 against hippuric acid. The limits of detection (LOD) and quantification (LOQ) for PGA were determined to be 0.5 mg/L and 1.6 mg/L, respectively. The recoveries of PGA ranged from 97.32% to 99.06%, with a relative standard deviation (RSD) lower than 4.6%. Furthermore, MIP(4VP)SPE demonstrated the potential for recycling up to three times without significant loss in analyte recovery. [ABSTRACT FROM AUTHOR]

The present work aims to produce functionalized polymer networks to target the bioactive molecule trans‐resveratrol found in winemaking residues, specifically at grape stems. The synergistic choice of photoinitiation, polymerization composition, and molecular imprinting approach allows the functionalization of these materials. Experimental design is applied to methodically perform the syntheses. The amount of crosslinker, the total monomer's concentration, and the ratio of trans‐resveratrol to the functional monomer 4‐vinylpyridine (4VP) are the factors selected for this experimental design. The binding capacities and the selectivity of the synthesized materials are assessed through sorption experiments in acetonitrile and hydroalcoholic media. Consequently, a multivariate linear regression analysis leads to describe the uptake of trans‐resveratrol by the materials in both media. The crosslinker content and the ratio of trans‐resveratrol to 4VP are found to be impactful parameters while designing such materials. These studies allow the identification of working conditions for sorption/desorption processes combining a high retention capability of the adsorbents with selectivity. Furthermore, four materials are selected to enrich trans‐resveratrol from grape stems extracts in a continuous process of solid‐phase extraction. The results show that the functionalized materials are able to enrich 12‐fold the content of trans‐resveratrol in some fractions demonstrating the interest of such polymers. [ABSTRACT FROM AUTHOR]