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Perfluoroalkyl substances (PFAS) are persistent organic pollutants that pose significant risks to human health and the environment. Efficient and selective enrichment of these compounds was crucial for their accurate detection and quantification in complex matrices. Herein, we report a novel magnetic solid-phase extraction (MSPE) method using fluorine-functionalized magnetic amino-microporous organic network (Fe 3 O 4 @MONNH 2 @F 7 ) adsorbent for the efficient enrichment of PFAS from aqueous samples. The core-shell Fe 3 O 4 @MONNH 2 @F 7 nanosphere was synthesized, featuring magnetic Fe 3 O 4 nanoparticles as the core and a porous amino-functionalized MONs coating as the shell, which was further modified by fluorination. The synthesized adsorbent material exhibited high specific surface area, hydrophobicity, and abundant fluorine groups, facilitating efficient and selective adsorption of PFAS via electrostatic attraction, hydrophobic-hydrophobic interactions, fluorine-fluorine interactions, π-CF interactions and hydrogen bonding. Furthermore, the MSPE method coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) allowed for the rapid, sensitive, and accurate determination of ultra-trace PFAS in real water samples, human serum, and human follicular fluid. Under optimal conditions, the established MSPE method demonstrated a linear range (2 to 2000 ng L - 1 ), with a correlation coefficient exceeding 0.9977, low limits of detection ranging from 0.54 to 1.47 ng L - 1 , with a relative standard deviation (RSD) < 9.1%. Additionally, the method showed excellent performance in complex real samples (recovery ratio of 81.7 to 121.6 %). The adsorption mechanism was investigated through kinetic, isotherm, and molecular simulation studies, revealing that the introduction of fluorine groups enhanced the hydrophobic interaction and fluorine-fluorine attraction between the adsorbent and PFAS. This work provides a proof-of-concept strategy for designing adsorbent materials with high efficiency and selectivity by post-modification, which has great potential for the detection and analysis of PFAS in complex samples., 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.)

In this study, a novel nitrogen-rich hyperbranched polymer was designed and synthesized via one-step precipitation copolymerization strategy. As possessing the lone-pair-electron-containing nitrogen atoms and positive-charged amine groups, as well as π electron-conjugated system, the prepared polymer displayed a strong tendency to adsorb protons acid, and negative-charged and conjugated compounds according to acid-base interaction, electrostatic interaction, and π-π stacking interaction. Based on these properties, a novel approach for assembling the proposed polymer coupled with high-performance liquid chromatography was successfully employed for selective enrichment and determination of auxins in plants. The extraction and desorption conditions were evaluated and the limits of detection and the limits of quantification of the proposed method were in the range of 0.15-0.29 μg L -1 and 0.49-0.98 μg L -1 for the four auxins based on the signal-to-noise ratio of 3:1 and 10:1, respectively. The recoveries of the target auxins from spiked plant samples were in the range from 85.0 to 116.3% with relative standard deviations lower than 9.6%. This study presented an inspiring thought for the construction of the versatile polymer adsorbent with highly efficient capturing of analytes from complex samples. Graphical abstract.

Transferrin (TrF) is a very important human body glycoprotein and a clinical biomarker which controls the body's iron ion channels and iron ion balance. Any change in TrF concentration and isoform also reflects the emergence of some diseases. In this work, we prepared magnetic molecularly imprinted nanoparticles (deep eutectic solvent-molecular imprinting polymers [DES-MIPs]) with a deep eutectic solvent (DES) as a functional monomer to separate TrF in human serum. The DES dosage for MIP, pH value, and time for adsorption have been optimized, and these materials show special adsorption properties for TrF. The maximum adsorption capacity (Q max ) and dissociation constant K L of the MIP by the Langmuir adsorption curve (R 2  = 0.9949) were 37.5 mg/g and 0.015 g/L, respectively. The imprinting factor of the MIP is 3.50 with relative standard deviation (5.63%). In summary, the use of DES as a functional monomer in molecular imprinting technology provides a novel, efficient, and biocompatible method for the isolation and purification of proteins. Graphical abstract ᅟ.

A novel approach for assembling homogeneous hyperbranched polymers based on non-covalent interactions with aflatoxins was developed; the polymers were used to evaluate the extraction of aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1 and AFG2) in simulant solutions. The results showed that the extraction efficiencies of three kinds of synthesized polymers for the investigated analytes were not statistically different; as a consequence, one of the representative polymers (polymer I) was used as the solid-phase extraction (SPE) sorbent to evaluate the influences of various parameters, such as desorption conditions, pH, ionic strength, concentration of methanol in sample solutions, and the mass of the sorbent on the extraction efficiency. In addition, the extraction efficiencies for these aflatoxins were compared between the investigated polymer and the traditional sorbent C18. The results showed that the investigated polymer had superior extraction efficiencies. Subsequently, the proposed polymer for the SPE packing material was employed to enrich and analyze four aflatoxins in the cereal powder samples. The limits of detection (LODs) at a signal-to-noise (S/N) ratio of 3 were in the range of 0.012-0.120 ng g(-1) for four aflatoxins, and the limits of quantification (LOQs) calculated at S/N=10 were from 0.04 to 0.40 ng g(-1) for four aflatoxins. The recoveries of four aflatoxins from cereal powder samples were in the range of 82.7-103% with relative standard deviations (RSDs) lower than 10%. The results demonstrate the suitability of the SPE approach for the analysis of trace aflatoxins in cereal powder samples., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A molecularly imprinted polymer was synthesized by ultrasonic irradiation, with attapulgite as matrix using β-naphthol as the template molecule, acryloyl-β-cyclodextrin as the functional monomer, and N,N-methylenebiacrylamide as the cross-linking agent, respectively. The imprinted polymer was characterized by infrared spectroscopy and transmission electron microscopy. Compared to polymers prepared by traditional heat sources, the molecularly imprinted polymer synthesized by ultrasonic irradiation had better selectivity and faster adsorption kinetics to estriol, estradiol, estrone and diethylstilbestrol. Using the imprinted polymer as the packing material for on-line solid-phase extraction, the above four estrogens in milk samples were concentrated and analyzed. The limits of detection for these estrogens were in the range of 1-8 ng g(-1) and reproducibility were less than 5.1% as RSDs (n=6) with milk samples spiked at 100 and 1000 ng g(-1) of each analyte., (Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.)

A novel molecularly imprinted polymer was synthesized with attapulgite employed as matrix, which is simple and time-saving. In this method, sudan I was chosen as template molecule, 2-vinylpyridine as functional monomer and ethylene glycol dimethacrylate as cross-linking agent, respectively. The imprinted polymer was characterized by the infrared spectroscopy and transmission electron microscopy. Then the selectivity experiments were performed on sudan dyes and the recognition coefficients for sudan I, sudan II, sudan III and sudan IV were 2.9, 1.9, 1.9 and 2.3, respectively. As the packing material of solid-phase extraction, the imprinted polymer has been applied to on-line concentration of the four sudan dyes in samples from Yellow River water, tomato sauce and sausage. The corresponding analytical methods to determine these sudan dyes have been developed. The limits of detection for these sudan dyes were in the range of 0.01-0.05 ng mL(-1) for Yellow River water, 1.0-3.0 ng g(-1) for tomato sauce and 0.8-3.0 ng g(-1) for sausage., (Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.)

Using nanoattapulgite as matrix, both diethylstilbestrol surface molecularly imprinted polymer and non-imprinted polymer were synthesized in this work. Compared with each other, the diethylstilbestrol surface molecularly imprinted polymer is superior to non-imprinted polymer in adsorption capacity, selectivity and mass transfer property. The maximum static adsorption capacities of diethylstilbestrol surface molecularly imprinted polymer, non-imprinted polymer and nanoattapulgite for diethylstilbestrol was 105.14, 78.54 and 28.50 mg g(-1), respectively. As the packing material of solid-phase extraction, the diethylstilbestrol surface molecularly imprinted polymer has been applied to concentrating diethylstilbestrol in pond water and fish samples. A corresponding analytical method to determine diethylstilbestrol has been developed. The limit of detection for diethylstilbestrol in pond water sample and fish samples were 3 microg L(-1) and 15 microg kg(-1).

The synthesis and evaluation of a molecularly imprinted polymer (MIP) as a selective matrix solid-phase dispersion (MSPD) sorbent, coupled with high-performance liquid chromatography for the efficient determination of chloramphenicol (CAP) in fish tissues are studied. The polymer was prepared using CAP as the template molecule, vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer, and sodium dodecyl sulfate as the surfactant in the presence of water as a solvent by miniemulsion polymerization. The CAP-imprinted polymers and nonimprinted polymers (NIPs) were characterized by Fourier transform IR spectroscopy, scanning electron microscopy, and static adsorption experiments. The CAP-imprinted material prepared showed high adsorption capacity, significant selectivity, and good site accessibility. The maximum static adsorption capacity of the CAP-imprinted and the NIP material for CAP was 78.4 and 59.9 mg g(-1), respectively. The relative selectivity factors of this CAP-imprinted material were larger than 1.9. Several parameters influencing the MSPD process were optimized. Finally, the CAP-imprinted polymers were used as the sorbent in MSPD to determine CAP in three kinds of fishes and resulted in satisfactory recovery in the range 89.8-101.43%. CAP-imprinted polymer as a sorbent in MSPD is better than C18 and attapulgite in terms of both recovery and percent relative standard deviation. The baseline noise was measured from a chromatogram of a blank fish sample which was treated after the MSPD procedure using CAP-imprinted polymer as a sorbent. Signal values of 3 times the noise (signal-to-noise ratio of 3) and 10 times the noise (signal-to-noise ratio of 10) were used to calculate the limit of detection and the limit of quantitation of the calibration curve. The limit of detection for CAP was 1.2 ng g(-1) and the limit of quantitation was 3.9 ng g(-1).

A novel magnetic organic porous polymer (denoted as Fe3O4@PC-POP) was developed for magnetic solid-phase extraction (MSPE) of two gastric cancer biomarkers (P-cresol and 4-hydroxybenzoic acid) from urine samples prior to high-performance liquid chromatographic analysis. The adsorbent was characterized by scanning electron microscope, transmission electron microscope, FTIR, powder X-ray diffraction, and other techniques. The result of dynamic light scattering shows that the particle size of the adsorbent is mainly distributed around 400 nm. Based on the design concept of the Fe3O4@PC-POP, the proposed material can effectively capture the target analytes through electrostatic and hydrophobic interaction mechanism. Furthermore, the enrichment conditions were optimized by the response surface method, and the method was utilized for the determination of P-cresol and 4-hydroxybenzoic acid in real urine samples from health and gastric cancer patients with high enrichment factors (34.8 times for P-cresol and 38.7 times for 4-hydroxybenzoic acid), low limit of detection (0.9–5.0 μg L−1), wide linear ranges (3.0–1000 μg L−1), satisfactory relative standard deviation (2.5%–8.5%), and apparent recoveries (85.3–112% for healthy people's and 86.0–112% for gastric cancer patients' urine samples). This study provides a guided principle for design of the versatile polymer with specific capturing of the target compounds from complex biological samples. [ABSTRACT FROM AUTHOR]

Macroscopic monoliths are highly desirable in many fields of application. Herein, well organized organic–inorganic cryogel composite with a three‐dimensional hierarchical meso‐ and macroporous structure are presented, which were produced by in situ copolymerization of mesoporous multifunctional silica (size: 1–20 μm; pore: 2–20 nm mostly) and monomers (hydroxyethyl methacrylate and diallyldimethylammonium chloride) in water below the freezing point. This copolymerization method effectively adjusted the macropores of the basic cryogel, and the nanosilica was more homogeneously dispersed in the basic cryogel. The specific surface area of the cryogel composite was increased 17 times versus than that of the basic cryogel. The abundant meso‐ and macroporous pores on the cryogel composite provided sufficient reactive sites favorable for the efficient mass transport of target compounds. When the cryogel composite, as solid phase extraction adsorbent, was coupled with high‐performance liquid chromatography, an analytical tool, the nucleosides were quantified with good selectivity, lower detection limits (0.9–1.3 ng/mL) and satisfactory recoveries of greater than 80% from spiked human serum. [ABSTRACT FROM AUTHOR]

Solid-phase microextraction with polysulfone and molecularly imprinted polymers as coating on nickel foam were used to adsorb and enrich floxacin drugs. The preparation method is simple and reproducible to obtain the materials with controlled thickness. After evaluation by scanning electron microscope and various adsorption experiments, the materials were used to adsorb analytes in water samples and biological samples. Coupling with chromatographic analysis, the method recoveries are satisfactory with 90.0-104.8% and 79.31-107.1% for water and biological samples. The method repeatability by intra- and interday experiments shows that the RSD values for water and biological samples were 1.0-9.9% and 1.7-10.3%, with the quantitative limits of three floxacin drugs as 3.0-6.2 μg L. [ABSTRACT FROM AUTHOR]

Abstract A green and promising sample pretreatment method was successfully established, which efficiently isolated proteins and small molecules in human serum. This method was achieved based on the multifunctional polymer, cryogel, as a solid phase extraction (SPE) monolith easily equipped in a syringe. The cryogel (pDC/GO-DE) was composed of diallyldimethyl ammonium chloride (DC) and 2-hydroxyethyl methacrylate (HE), which was further modified with graphene oxide (GO) and N-diethylethanamine hydrobromide (DE). Various proteins, including bovine serum albumin (BSA), lysozyme (Lys), γ-globulins, immunoglobulin G (IgG), transferrin, small molecules (ribavirin, adenosine, ofloxacin, estriol, rutin, amoxicillin, ibuprofen, 1-methyl-3-phenyl-propylamine, and benzylamine) and their mixtures were successively studied as model analytes to evaluate the new material and demonstrate the isolation mechanism, which was mainly dependent on mixed-mode ion-exchange and the hybrid hydrophobicity-hydrophilicity property of pDC/GO-DE cryogel. Moreover, the three-dimensional macroporous structure contributed to the underlying size-selective isolation. When 10 times diluted human serum was used as the sample, more than 95% of proteins were adsorbed within 10 min under physiological conditions, and the interference matrix in serum was also efficiently reduced. After recycling three times, the extraction ratio of proteins in human serum was still higher than 90%. When four small molecules (camptothecin, ribavirin, 1-methyl-3-phenylpropylamine and ofloxacin) were added to blank human serum, their recoveries were within 65.6–81.8%, and were comparable to those obtained by protein precipitation method (63.7–83.2%). Graphical abstract fx1 Highlights • A new cation crosslinker diallyldimethylammonium chloride was employed firstly to prepare novel 3D cryogel composites. • Self-assembly of graphene oxide and polyethyleneimine was used to construct the 3D cryogel composites. • Water is the only used solvent to prepare the green cryogel composites. • The new cryogel was used as an absorbent to isolate proteins and small molecules. • The new method showed the high-efficiency isolation for human serum sample. [ABSTRACT FROM AUTHOR]

A kind of new temperature sensitive molecularly imprinted polymer (MIP) with ofloxacin (OFL) as template was prepared for the coating of solid phase microextraction (SPME). Dopamine was self-polymerized on stainless steel fiber (SSF) as the SPME support followed by silanization. Then MIP was synthesized as SPME coating on the modified SSF in a capillary, with N -isopropyl acrylamide as temperature sensitive monomer and methacrylic acid as functional monomer. The synthesis could be well repeated with multiple capillaries putting in the same reaction solution. The obtained MIP fiber was evaluated in detail with different techniques and various adsorption experiments. At last the MIP fiber was used to extract the OFL in milk. Satisfied recoveries between 89.7 and 103.4% were obtained with the limit of quantification (LOQ LC ) of 0.04 μg mL −1 by the method of SPME coupled with high performance of liquid chromatography (HPLC). [ABSTRACT FROM AUTHOR]

Highlights: [•] We used click reaction to prepare a new type of polymer as the monolith column. [•] The polymer was porous and could enrich PAHs well up to 100 to more than 1000 times. [•] The π–π stacking interaction and the effect of small size played dominant roles to the strong adsorption affinity of the polymer monolith. [•] A sensitive on-line SPME–HPLC method was set up for determination of PAHs. [Copyright &y& Elsevier]

Abstract: The liquid chromatography–electrospray ionization-tandem mass spectrometer (LC–MS/MS) method coupled with an automated solid-phase extraction procedure has been developed to identify 22 psychiatric pharmaceuticals, including seven anxiolytic-sedative-hypnotics, six antidepressants, and nine anti-schizophrenia drugs, in wastewater samples from two psychiatric hospital wastewater treatment plants (P-WWTPs) and three municipal wastewater treatment plants (M-WWTPs) in Beijing, China. Analyte recoveries from spiking experiments in the WWTP influent and effluent at three concentrations ranged from 70% to 110%, excluding sulpiride, ziprasidone, and olanzapine. Method detection limits for five, eight, and nine analytes in the WWTP influent and effluent were 20–80, 1–16, and <1ngL−1, respectively. High psychiatric pharmaceutical concentrations (e.g., ∼942ngL−1oxazepam, 5552–12,782ngL−1 clozapine, 2762–9832ngL−1sulpiride, and 2030–4967ngL−1quetiapine) were frequently observed in P-WWTP influent compared to M-WWTPs. Although P-WWTPs typically had higher removal rates, significantly higher concentrations of the target compounds were observed in the P-WWTP secondary effluent than in the M-WWTP influent (e.g., ∼752ngL−1oxazepam, ∼8183ngL−1 clozapine, ∼10,833ngL−1sulpiride, and ∼1168ngL−1quetiapine). Thus, the discharge control of psychiatric pharmaceuticals from psychiatric hospitals requires improvement. [Copyright &y& Elsevier]

Abstract: A porous polysulfone microcapsule containing organic modified montmorillonite and magnetic nanoparticles (OMMT-Fe3O4@PSF) has been successfully prepared by a phase-inversion method and evaluated as a magnetic solid-phase extraction (MSPE) sorbent for clean-up and enrichment of 4-chlorophenol (4-CP) and 2-chlorophenol (2-CP) in aqueous samples. Compared with a microcapsule containing the conventional extraction sorbent C18 (C18-Fe3O4@PSF), OMMT-Fe3O4@PSF had much lower cost, a faster adsorption rate, and superior uptake amounts for the investigated analytes. The proposed microcapsule has been developed for the extraction of 4-CP and 2-CP from environmental water samples and their analysis by high-performance liquid chromatography with UV detection (HPLC-UV). Various parameters, such as pH, extraction time, the mass of sorbent, and the desorption conditions, have been evaluated and the calibration curves of the chlorophenols were linear (R 2 ≥0.9985) in the range from 1.01 to 104.5ngmL−1. The limits of detection at a signal-to-noise (S/N) ratio of 3 were 0.22 and 0.17ngmL−1 and the limits of quantification calculated at S/N=10 were 1.52 and 1.07ngmL−1 for 2-CP and 4-CP, respectively. The recoveries of 2-CP and 4-CP from natural water and the treated wastewater samples were in the range of 84.4–115% with relative standard deviations (RSDs) lower than 7.0%. The results have demonstrated the suitability of the MSPE approach for the analysis of trace chlorophenols in aqueous samples. [Copyright &y& Elsevier]