Solid-phase Extraction Adsorbent Research Articles

Facile and rapid preparation of fluorinated imprinted adsorbent for magnetic solid phase extraction of liquid-crystal monomers.

Anew fluorinated imprinted adsorbent (MIA) for magnetic solid phase extraction (MSPE) ofliquid crystal monomer (LCM) pollutantswas one-pot prepared within 3.5h using 4-[difluoro(3,4,5-trifluorophenoxy)methyl]-3,5-difluoro-4'-ethyl-biphenyl (DFBP) as template and 1H,1H,2H,2H-heptadecafluorodecyl acrylate/vinylanthracene as dual monomers. The structure, morphology, and magnetic properties of MIA fabricated were investigated by various characterization techniques. Under the optimal conditions the prepared MIA presented satisfactory specific recognition performance. The recognition factor and adsorption capacity towards DFBP were 2.7 and 15.9mg/g, respectively. The specific recognition behaviors of MIA/MSPE towards DFBP were surveyed by means of adsorption kinetics and adsorption isotherms. Combining MSPEwith HPLC coupled to a diode array detector (DAD), asensitive, reliable and anti-interference method for the monitoring of LCMs residuals in various environmental water and soil samples was established. The achieved enrichment factors were 132-248 and 96-204 in water and soil samples, respectively. The corresponding limits of detection were 0.0017-0.0051μg/L and 0.087-0.28μg/kg, respectively. Moreover, confirmatory experiments were adopted to inspect the accuracy of theestablished MIA/MSPE-HPLC/DAD approach. To the best of our knowledge, this is the first time that an imprinted material has been used forspecific isolation and capture of LCMs which have been classified as emerging organic pollutants.

A Cu/β-cyclodextrin/reduced graphene oxide nanocomposite for efficient and multi-aflatoxin detection in rice, ginger and bean samples.

Aflatoxins (AFs) are some of the most important mycotoxins or fungal toxins that cause contamination of food products and are considered a threat to human and animal health. An efficient Cu/β-cyclodextrin/reduced graphene oxide nanocomposite (Cu/β-CD/rGO) has been prepared and applied as a new solid-phase extraction adsorbent for the separation and preconcentration of four AFs (B1, B2, G1, and G2) using high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The successful synthesis of the prepared nanocomposite was confirmed using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The impacts of pH, amount of adsorbent, sample volume, desorption solvent volume, and salt concentration on the recovery of AFs were precisely investigated and optimized by central composite design (CCD). Under the optimal conditions, the introduced method demonstrated good linearity in the range of 0.4-5.4, 0.08-1.08, 0.4-5.4, and 0.08-1.08 ng g-1 for AFs B1, B2, G1 and G2, respectively. The limits of detection and quantification for the four AFs were obtained in the range of 0.06-0.53 and 0.20-1.62 ng g-1, respectively. The accuracy of the method was evaluated using recovery measurements in spiked real samples such as rice, bean, and ginger samples, and satisfactory recoveries were obtained in the range of 83.5-109.0% with good precision (RSDs between 2.4 and 8.6%). The results of this research revealed that our developed method is sensitive, highly effective, and convenient to perform for the trace analysis of AFs in different real samples.

Synthesis of reusable hierarchical Pore PVDF-MIL-101(Cr) foam for Solid phase extraction of fluoroquinolones from water and its adsorption behavior for anionic and cationic dyes

In this study, a novel hierarchical pore MIL-101(Cr) foam (HPF-MIL-101) was designed and prepared using the sacrificial template method with NaCl as the sacrificial template. This method involved grinding, heating, and washing the NaCl template to produce HPF-MIL-101, with PVDF as the binder and MIL-101(Cr) as the adsorbent. This preparation process is both straightforward and cost-effective, avoiding the use or generation of any organic reagents, thereby offering an environmentally sustainable approach for producing metal-organic framework (MOF) composites. The prepared HPF-MIL-101 exhibited excellent adsorption capabilities for both anionic dye (methyl orange, MO) and cationic dye (methylene blue, MB). The adsorption process followed a pseudo-second-order kinetic model and Friedrich isotherm model, indicating a multilayer adsorption. This is further supported by the Weber-Morris intraparticle diffusion model, which divided the adsorption process into three stages. Furthermore, the adsorption process was consistent with the Freundlich isotherm model, with a correlation coefficient (r) greater than 0.96. HPF-MIL-101 can also be used as an adsorbent for solid phase extraction (SPE). Therefore, an SPE method combined with high-performance liquid chromatography (HPLC) was developed using HPF-MIL-101 as the adsorbent to analyze five fluoroquinolones (FQs) in water samples. This analytical method showed good linearity in the range of 30–2000 ng·mL−1, with excellent linear correlation coefficient (r = 0.9991–0.9999), reasonable extraction recoveries ranging from 80.39 to 112.7 % (RSD ≤ 7.9 %), and low limits of detection (8–30 ng·mL−1). Overall, the results indicated that HPF-MIL-101 not only had a simple, environment-friendly, and pollution-free preparation process but also can be reused for enrichment and detection of trace FQs in water. Thus, HPF-MIL-101 exhibits immense application potential in environmental pollutant removal and also provides a valuable reference for the preparation and application of other MOF composites.

Methylated magnetic covalent organic framework for sample preparation and LC-MS/MS detection of 12 tadalafil analogs in dietary supplements

Tadalafil analogs are often illegally added to dietary supplements such as herbal beverages, protein powders and tablet foods. Due to the complexity of the matrices, effective extraction of tadalafil analogs is the key to achieve accurate quantification. Therefore, it is of great significance to establish a rapid and effective method for the analytical determination of tadalafil analogs in complex matrices. In this study, a novel methylated magnetic covalent organic framework, Fe3O4@TFPB-OT, was successfully synthesized under mild conditions. Fe3O4@TFPB-OT demonstrated robust adsorption capabilities, with capacities ranging from 52.4 to 90.9 mg/g for the tadalafil analogs. Several pre-enrichment parameters were optimized, including adsorbent dosage, extraction time, pH, shaking time, elution solvent, and desorption time. The applicability of Fe3O4@TFPB-OT was evaluated as effective adsorbents for the magnetic solid-phase extraction (MSPE) of 12 tadalafil analogs in dietary supplements. Combined with high-performance liquid chromatography-tandem mass spectrometry, the limits of detection (LODs) of this method ranged from 0.005 to 0.05 μg/L in liquid matrices and from 0.005 to 0.05 μg/kg in solid matrices, showing good sensitivity and recoveries ranged from 56.1 % to 90.9 %with relative standard deviations lower than 3.9 %, demonstrating good accuracy and precision. Additionally, the adsorbent retained its effectiveness after at least ten reuse cycles, indicating significant reusability. This study provides an effective method for the analysis and detection of tadalafil analogs in dietary supplements and has great potential for application.

MCM-41 based dispersive micro-solid phase extraction of selected cephalosporin antibiotic residues from water samples prior to liquid chromatographic quantification

The occurrence of antibiotics in water bodies is of concern owing to the serious risk they pose to the environment, water security, aquatic organisms, and human health. In this study, mesoporous silica (MCM-41) nanostructured material was synthesised and characterized by various analytical techniques to determine its morphology and dimension, functional groups, surface charge, and textural properties. The nanostructured MCM-41 was used as an adsorbent in ultrasound-assisted dispersive micro solid-phase extraction (UA-D-µ-SPE) of cefadroxil (CFDX) and cephalexin (CPLX) in water samples. The concentration of the analytes in aqueous solution and real water samples was determined using high-performance liquid chromatography coupled with diode array detection (HPLC-DAD). The developed method for CFDX and CPLX in various water samples exhibited relative linear ranges of 0.1–600 µg/L and 0.1–550 µg/L, respectively, and correlation coefficients ranging from 0.9923–0.9993. Under optimum condition, the UA-D-µ-SPE/HPLC-DAD method displayed low limits of detection (LOD) and quantification (LOQ), with values ranging from 0.02–0.16 µg/L and 0.067–0.53 µg/L, respectively. The investigated intraday and interday accuracy in spiked water samples showed acceptable extraction efficiencies with a range of 73.5–98.1% and a relative standard deviation less than 6.0%. Moreover, the performance of MCM-41 was also assessed for the removal of cephalosporin antibiotics aqueous solutions. The kinetic and isotherm studies revealed that the adsorption process followed pseudo-second order and the Langmuir model, respectively. Furthermore, the maximum adsorption capacities for CFDX and CPLX were 43.2 and 47.8 mg/g. Lastly, the UA-D-µ-SPE/HPLC-DAD method was successfully applied in extracting, preconcentrating, separating and determining CFDX and CPLX in wastewater and surface water samples. These results demonstrated that MCM-41 can be applied in the removal of cephalosporin antibiotics from aquatic environments.

Synthesis of β-cyclodextrin magnetic-graphene-oxide pyrenyl (β-mGOP) gels for high-throughput enrichment and detection of various trace mycotoxins in food using UHPLC-cIMS

In this research, β-cyclodextrin magnetic-graphene-oxide pyrenyl gel composite (β-mGOP) was employed to remove trace mycotoxins from food products. The β-mGOP gels exhibited a three-dimensional macroporous structure that facilitated the rapid diffusion of target molecules into the nanoporous structure of the covalent organic frameworks embedded within the gel. The adsorption process of mycotoxins onto the β-mGOP gels conformed to the pseudo-second-order kinetics and the Freundlich adsorption model. These findings demonstrated exceptional rapid adsorption kinetics without pore collapse, making the material suitable as fillers for solid-phase extraction adsorbents. Additionally, a novel screening technique utilizing β-mGOP gels in conjunction with cyclic ion mobility mass spectrometry was developed to illustrate the efficacy of β-mGOP gels in capturing various trace substances in food and enhancing detection resolution. The versatile, uncomplicated, and scalable characteristics of β-mGOP gels indicate their promising potential for future applications in high-throughput analysis of trace contaminants in food.

Developing a novel pyridine-based ionic porous organic polymer with functional group for highly efficient extraction of phenolic endocrine disruptors in natural water and tilapia fish

A pyridine-based ionic porous organic polymer bearing hydroxyl groups (OH-iPOP) was developed for the first time by quaternization and crosslinking of 4-pyridinemethanol with 4,4′-bis(chloromethyl)biphenyl. OH-iPOP exhibited strong adsorption capacity for endocrine disruptors (EDs) including bisphenol A, bisphenol F, p-tert-butylphenol and bisphenol B (82.59–183.9 mg g−1), much higher than that of commercial adsorbents. The adsorption mechanism of OH-iPOP to EDs involved π-π⁎ interaction, hydrogen bond and electrostatic interaction. Using OH-iPOP as solid phase extraction adsorbent combined with high-performance liquid chromatography, a reliable method for the sensitive detection of trace EDs in natural water and tilapia fish was established. The detection limits (S/N = 3) were 0.01–0.04 ng mL−1 and 1.00–3.80 ng g−1 for natural water and tilapia fish, respectively. The method recoveries ranged from 81.5 % to 116 %. This work not only develops an efficient adsorbent for the enrichment of EDs, but also provides a new strategy for the synthesis of novel cationic POPs.

Solid phase extraction-surface enhanced Raman spectroscopy (SPE-SERS) test of antibiotic residues in Milk based on au@ MIL-101 NPs

A SPE-SERS method was developed for the detection of several antibiotic residues in dairy products. Gold nanoparticles (Au NPs) encapsulated with an ultrathin Cr-MIL-101 shell (Au@Cr-MIL-101 NPs) have been synthesized, and the thickness of Cr-MIL-101 shell can be precisely controlled to 3 nm. As a superior solid phase extraction (SPE) adsorbent, Cr-MIL-101 acts as a shell layer to effectively enrich antibiotics within the localized surface plasmon resonance (LSPR) field of Au NPs, which enhances the SERS signal and eliminates background interference. The method can achieve highly sensitive and high-throughput detection for tetracycline hydrochloride, sulfapyridine and benzylpenicillin sodium in dairy products, and the detection limits (LOD) are as low as 2.237, 2.644 and 4.662 ppb respectively. The recoveries of antibiotic residues in spiked dairy products ranged from 72.31 % to 146.7 % with matrix effects (ME) of −15.13 % to 28.68 %. Thus, this method holds significant promise for rapid detection of antibiotics in milk.

Extraction of methamphetamine and pseudoephedrine by modified graphene oxide solid phase extraction method coupled to HPLC-UV in urine sample.

Methamphetamine, pseudoephedrine, and related drugs are among the first drugs used for the stimulation of the central nervous system. In this study, two adsorbents based on graphene oxide (GO) were synthesized and used for the analysis of methamphetamine and pseudoephedrine. The prepared nano-adsorbents based on GO in this study were coated by polyaniline (PANI) and Fe3O4/C-nanodot/GO (magnetic adsorbent). The average size of nanoparticles (GO/PANI) was 18.43nm. The specific surface area and pore size diameter of Fe3O4/C-nanodot/GO were 22.71 m2 g- 1 and 15.23nm, respectively. Experimental variables affecting the extraction efficiency of the analytes such as pH of the sample solution, amount of adsorbent, extraction time, and type of eluents were investigated and optimized by response surface methodology. Under optimum conditions, GO/PANI and Fe3O4/C-nanodot/GO were considered appropriate solid phase extraction adsorbents for HPLC-based analyses of the studied drugs in human urine samples. However, GO/Fe3O4 nano adsorbent (Fe3O4/C-nanodot/GO) showed superior working condition than GO/PANI. The validated proposed analytical methods can be used for the quantitative determination of methamphetamine and pseudoephedrine in actual samples.

Cost-effective synthesis and application of Cu²⁺-doped melamine formaldehyde resin for enhanced tetracycline enrichment in environmental water

Tetracycline antibiotics (TCs) are typically present at low residue levels in environmental water, necessitating enrichment prior to analysis. In this study, a Cu2+-doped melamine formaldehyde resin (Cu-MFR) was synthesized to enhance the adsorption efficiency for TCs, leveraging the formation of stable Cu2+-TC complexes on the sorbent surface. Then it was used as an adsorbent in solid-phase extraction (SPE) for the enrichment of four TCs from water samples. The optimized parameters for Cu-MFR in the analysis of TCs in environmental water enabled linear detection ranges from 0.20 to 50 ng/mL, with relative recoveries ranging from 79.5 % to 97.6 % and relative standard deviations ≤ 10.0 %, using high-performance liquid chromatography-tandem high-resolution mass spectrometry (HPLC-HRMS). The limits of detection for the four TCs were determined to be between 0.11 and 0.16 ng/mL, indicating its potential for practical application in real sample analysis.

Hydrophilic-lipophilic balance copolymer composite nanofiber as an adsorbent for online solid phase extraction of three estrogens from water samples with column-switching prior to high-performance liquid chromatography

Hydrophilic-lipophilic balance copolymer composite nanofiber as an adsorbent for online solid phase extraction of three estrogens from water samples with column-switching prior to high-performance liquid chromatography

Highly sensitive detection of organophosphorus pesticides in water using a carboxyl-functionalized magnetic covalent organic framework

The development of novel methods for the precise quantification of organophosphate pesticides (OPPs), with enhanced accuracy, sensitivity, and efficiency, is crucial for environmental monitoring and human health risk assessment. In this study, Fe3O4@SiO2@COF-COOH magnetic core–shell nanoparticles were synthesized by coating a carboxyl-functionalized covalent organic framework (COF-COOH) onto the surface of amino-modified silica-coated iron(III) oxide particles (Fe3O4@SiO2-NH2). The incorporation of carboxyl groups, covalent organic framework and magnetic properties imparted superior performance to the adsorbent in magnetic solid-phase extraction (MSPE) of polar compounds from complex sample matrices. An analytical method based on Fe3O4@SiO2@COF-COOH coupled with GC–MS/MS was developed for the determination of eight organophosphate pesticide residues in river water near farmland. The established method displays good linearity in the range of 0.1–500 ng/mL for four OPPs and 1–2000 ng/mL for the other four, with correlation coefficients between 0.9903–0.9983. The LODs (S/N = 3) and LOQs (S/N = 10) were determined to be in the ranges of 0.53–9.6 ng/L and 1.8–31.9 ng/L, respectively. The adsorption mechanism was characterized by density functional theory calculations. Furthermore, the established method was successfully applied to analyze the distribution of trace OPPs in real river water samples collected from various cities in Henan Province. Its rapid, straightforward, and efficient ability to enrich trace levels of OPPs from complex real-world samples makes it a valuable tool for environmental monitoring, food safety, and human health management.

Enhanced Pb(II) extraction using a novel chitosan/pectin/carbon composite adsorbent for solid-phase extraction

ABSTRACT This research aimed to present the development of chitosan/pectin/carbon (CPC) materials as adsorbents in the solid-phase extraction (SPE) of Pb(II) from river water samples. The CPC adsorbent shows active groups effectively binding Pb(II) ions. The characterisation included using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy (SEM-EDX) to analyse functional groups and evaluate surface morphology with elemental composition. SPE parameters were systematically optimised to enhance adsorption-desorption efficiency, including pH 4.0, Pb(II) concentration of 5 mg L−1, flow rate of 13.3 mL min−1, elution flow rate of 12.8 mL/min using nitric acid (HNO3), a sample volume of 25 mL, eluent volume of 1 mL and concentration at 1.0 M. The results showed that the implementation of the refined CPC-based SPE method for Pb(II) analysis in water samples obtained a recovery range of 101% to 103%, accompanied by a significant 25-fold concentration enrichment of Pb(II). Moreover, the adsorption concentration increased from undetectable levels to 1.27–2.48 mg L−1, reporting the efficacy of the CPC-based SPE method for sensitive and accurate Pb(II) analysis in environmental samples.

Highly selective guanidine-linked covalent organic framework for efficient removal of perfluoroalkyl carboxylic acids from water samples

In this study, guanidine-linked covalent organic framework (TPDGCl) was synthesized via a solvothermal method. The presence of guanidine groups in its structure facilitates electrostatic interactions and provides hydrogen bonding sites, enabling the selective enrichment of perfluoroalkyl carboxylic acids (PFCAs) from environmental water samples. The material exhibits rapid kinetic mass transfer, which facilitates the efficient removal of samples containing PFCAs from aqueous solutions within 5 min. Furthermore, TPDGCl exhibits several advantageous properties, including high selectivity for PFCAs, a high adsorption capacity (2005 mg/g), excellent chemical stability, and remarkable recyclability (five cycles). Additionally, density functional theory (DFT) studies have demonstrated that the adsorption of PFCAs on TPDGCl is enhanced by ion exchange, hydrophobic interactions, hydrogen bonding interactions and ordered channel structures. Finally, TPDGCl was used as an adsorbent for dispersive solid-phase extraction (d-SPE), in combination with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), to develop an analytical method for the efficient extraction and sensitive detection of PFCAs. The developed method exhibits highly sensitivity, with detection and quantification limits of 0.64–0.85 ng/L and 2.6–3.4 ng/L, respectively. The recoveries of actual water samples ranged from 75.4% to 113.7%. Moreover, TPDGCl effectively reduces the levels of PFCAs in real water samples to less than 70 ng/L within only 1 h. These results indicate that TPDGCl is an effective adsorbent for removing PFCAs from environmental water samples.

A hierarchical porous Fe3O4-COOH@H-ZIF-67 composite as magnetic solid-phase extraction adsorbent for benzimidazole pesticides

A hierarchical porous structural magnetic zeolite imidazolate framework-67 composite (Fe3O4-COOH@H-ZIF-67) was prepared through directly mixing the H-ZIF-67 and glutaric anhydride functionalized Fe3O4 nanospheres, of which the H-ZIF-67 was synthesized through a double template pore size regulation method. The successful preparation of Fe3O4-COOH@H-ZIF-67 composite was confirmed based on the material characterization using different techniques. The prepared composite was applied in the efficient removal of four benzimidazole pesticides (BZDs) in water using magnetic solid-phase extraction (MSPE) process. The results of static and dynamic adsorption experiments indicate that the adsorption of BZDs on Fe3O4-COOH@H-ZIF-67 follow pseudo-second-order kinetics, the Langmuir model fitted well with the adsorption data (R2 are all higher than 0.9969), and the maximum adsorption capacity for BZDs are 7.44–31.11 mg/g. Meanwhile, the adsorption mechanism study indicate that both hydrogen bonding and coordination play important roles during the adsorption process of BZDs. Finally, the developed MSPE method was combined with HPLC analysis and applied in the removal of BZDs from simulated pesticides wastewater. The removal rate was 82.76–96.18 %, and the treated samples met the requirements of the maximum residue limits of CBZ in the national standard GB 21523–2008. In addition, the adsorbent can be used at least three times and the extraction efficiency changed within 3 % after being stored in dry atmosphere at room temperature for 90 days. The results of this work manifested that Fe3O4-COOH@H-ZIF-67 composite can be used for removal and analysis of BZDs in complex samples.

Preparation and evaluation of polymeric ionic liquid functionalized microparticles as the efficient adsorbent for pipette tip solid phase extraction of sulfonamides

Sulfonamides (SAs) residues are commonly found in environmental samples, which is highly concerning for public safety and environmental protection. The detection of SAs is quite important but challenging. In this work, a kind of polymeric ionic liquid functionalized microparticles (PIL-FM) was synthesized via a simple free radical polymerization reaction, and applied as the adsorbent for pipette tip solid phase extraction (PT-SPE) of three SAs from river water, milk powder and honey samples. The adsorption performance of PIL-FM on SAs were evaluated using adsorption kinetics and adsorption isotherms, and the results showed that PIL-FM had the best selectivity for SMZ with the maximum adsorption capacity was as high as 45.05 mg·g−1. The extraction process was optimized and the adsorption mechanism was preliminarily discussed. PIL-FM has the excellent selectivity for SAs mainly because of the strong π-π interaction, and the electrostatic repulsion between them in the elution step also has a positive impact. Under optimal conditions, combined with HPLC, this PT-SPE method had wide linearity (0.2–100 μg·L−1, R2 ≥ 0.9998) and low limits of detection (0.06–0.08 μg·L−1). The intra-day and inter-day repeatability were found to be 3.7 %–4.6 % and 4.5 %–6.2 %, respectively. The suggested PT-SPE method is simple, low cost, rapid, and efficient to extract SAs, and can be applied for the monitoring of SAs residues in the aquatic environment and in food.

Polypyrrole as Adsorbent in Magnetic Solid Phase Extraction for Progesterone Determination from Human Plasma.

A straightforward and effective chromatographic method has been created for the analysis of progesterone from human plasma using a composite based on polypyrrole/magnetic nanoparticles in the sample preparation procedure. The quantification of progesterone is necessary due to its importance in human development and fertility. The employed conditions used acetonitrile:ultrapure water (70:30, v/v) as the mobile phase at 1.0 mL min-1 and an octadecyl silane column (Phenomenex Gemini, 250 mm × 4.6 mm, 5 μm) at a wavelength of 235 nm. The composite and its precursors were synthesized and properly characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy/energy dispersive spectroscopy, thermogravimetric analysis, and point of zero charge. The main factors affecting the extraction recovery of progesterone from pool human plasma samples employing magnetic solid phase extraction have been studied, such as sample pH (without adjustment), sample volume (1000 μL), washing solvent (ultrapure water), eluent (acetonitrile), eluent volume (1000 μL), and amount of adsorbent (10 mg). The extraction recoveries ranged from 98% to 102%, and linearity ranged from 5 to 3000 ng mL-1. The correlation coefficient (r) was ≥0.99, and acceptable relative standard deviation (precision), relative error (accuracy), and p-values (robustness) were observed. Lastly, the plasma samples from pregnant women were successfully analyzed by the validated method.

Development of amphiphilic hypercrosslinked porous polymers for magnetic extraction of multiple environmental pollutants in water

Under the principle of similar compatibility, researchers have developed various polarity extractants corresponding to a class of chemicals. Separating different polarities chemicals with one extractant effectively has become a novel research trend in separation science. Given the complexity of environmental sample matrices and the significant differences in polarity and solubility of various compounds, the introduction of hydrophilic groups to hydrophobic material skeletons can lead to sorbents with hydrophilic-lipophilic balance (HLB) property and thus improve their extraction performance for substances with different polarities. In this work, a hypercrosslinked polymer (HCPPz-TPB), designated as HLB, was synthesized by incorporating polar pyrazine and nonpolar triphenylbenzene molecules within each other. Subsequently, a core-shell magnetic composite material was obtained by encapsulating magnetic Fe3O4 nanoparticles in HCPPz-TPB. The material was applied as an adsorbent for magnetic solid phase extraction (MSPE) and combined with a high-performance liquid chromatography-photodiode array detector (HPLC-PDA) to enrich, separate, and detect seven polar contaminants in environmental water samples. The proposed approach, Fe3O4@SiO2@HCPPz-TPB−MSPE-HPLC-PDA, is characterized by its outstanding high sensitivity, low detection limits, wide linear range, and good reproducibility. The method demonstrated satisfactory linearity in the range of 0.05–2 μg mL-1 with R2 values between 0.9969 and 0.9997; the limits of detection (LOD) were observed to be within the range of 0.0019–0.016 μg L-1, and limits of quantification (LOQ) was observed to be within the range of 0.0064–0.054 μg L-1 range with good precision. The recoveries of the different contaminants in the environmental samples ranged from 83.61 to 116.46% (RSD≤10.56, n = 5). The new hydrophilic-lipophilic balance extractant is highly efficient, sensitive, and precise for extracting different polar pollutants. The findings demonstrate that the Fe3O4@SiO2@HCPPz-TPB display a remarkable affinity for multiple targets, driven by complex interactions including multi-stackings and hydrogen bonding as a sorbent. The synthesized Fe3O4@SiO2@HCPPz-TPB may be employed in diverse applications, including extraction, removal, and determination of diverse trace multi-target analytes in complex media.

Surface amphiphilic hybrid porous polymers based on cage-like organosiloxanes for pipette tip solid-phase extraction of microcystins in water

The occurrence of microcystins (MCs) during harmful algal blooms (HABs) represents a major threat to freshwater environments. In this work, a novel surface amphiphilic hybrid porous polymers based on cage-like organosiloxanes (PCSs) was prepared for the enrichment of MCs. The copolymerization of bifunctional amphiphilic monomers, 2-methacryloyloxyethyl phosphorylcholine (MPC) and N-benzylquininium chloride (BQN), with the cross-linker methacryl substituted polyhedral oligomeric silsesquioxane (POSS) was achieved in an ionic liquid-based porogenic medium. The hierarchical porous structure, a variety of surface functional groups and weak hydrophilicity were well characterized on the prepared materials using scanning electron microscopy, nitrogen adsorption/desorption analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, zeta potential analysis and water contact angle testing, respectively. The as-prepared surface amphiphilic PCSs was used as an adsorbent for pipette tip solid-phase extraction (PT-SPE) to enrich microcystins (MCs) from surface waters before their analysis by capillary electrochromatography (CEC) and liquid chromatography-mass spectrometry (LC-MS). Under the optimal conditions, the established PT-SPE-LC-MS method exhibited a wide linear range (10–10,000 ng L−1), low limits of detection (4.0–8.0 ng L−1) and satisfactory recoveries (89.5–102.8 %) for MCs. An adsorption mechanism involving electrostatic interactions, hydrogen bonding, hydrophilic interactions, and π-π stacking has been proposed. The findings suggest that the use of surface amphiphilic PCSs materials as adsorbents in the PT-SPE platform facilitates efficient enrichment of MCs for subsequent chromatographic analysis. These investigations offer a new perspective on the simple and uncomplicated pretreatment of complex environmental samples.

Preparation of Polydopamine-Based Electrospun Nanofibers as an Efficient Adsorbent for Solid-Phase Extraction of Trace Mycotoxins Followed by HPLC

Preparation of Polydopamine-Based Electrospun Nanofibers as an Efficient Adsorbent for Solid-Phase Extraction of Trace Mycotoxins Followed by HPLC