Green construction of Fe3O4@GC submicrocubes for highly sensitive magnetic dispersive solid-phase extraction of five phthalate esters in beverages and plastic bottles

Recent advancements in the extraction and analysis of phthalate acid esters in food samples

Phthalate acid esters (PAEs) are ubiquitous environmental pollutants present in food samples, necessitating accurate detection for risk assessment and remediation efforts. This review provides an updated overview of the recent progress on the PAEs analysis regarding sample pretreatment techniques and analytical methodologies over the latest decade. Advances in sample preparation include solid-based extraction techniques replacing conventional liquid-liquid extraction, with solid sorbents emerging as promising alternatives due to their minimal solvent consumption and enhanced selectivity. Although techniques like the microextraction methods offer versatility and reduced solvent reliance, there is a need for more efficient and environmentally friendly techniques enabling on-site portable detection. High-resolution mass spectrometry is increasingly utilized for its enhanced sensitivity and reduced contamination risks. However, challenges persist in developing in situ analytical techniques for trace PAEs in complex food samples. Future research should prioritize novel analytical techniques with superior sensitivity and selectivity, addressing current limitations to meet the demand for precise PAEs detection in diverse food matrices.

Solvent and monomer regulation synthesis of core-shelled magnetic β-cyclodextrin microporous organic network for efficient extraction of estrogens in biological samples prior to HPLC analysis

The abnormal estrogens levels in human body can cause many side effects and diseases, but the quantitative detection of the trace estrogens in complex biological samples still remains great challenge. Here we reported the fabrication of a novel core-shell structured magnetic cyclodextrin microporous organic network (Fe3O4@CD-MON) for rapid magnetic solid phase extraction (MSPE) of four estrogens in human serum and urine samples prior to HPLC-UV determination. The uniform spherical core-shell Fe3O4@CD-MONs was successfully regulated by altering the reactive monomers and solvents. The Fe3O4@CD-MONs owned high specific surface area, good hydrophobicity, large superparamagnetism, and abundant extraction sites for estrogens. Under optimal conditions, the proposed MSPE-HPLC-UV method provided wide linearity range (2.0-400 μg L-1), low limits of detection (0.5-1.0 μg L-1), large enrichment factors (183-198), less adsorbent consumption (3 mg), short extraction time (3 min), and good stability and reusability (at least 8 cycles). The established method had also been successfully applied to the enrichment and detection of four estrogens in serum and urine samples with a recovery of 88.4-105.1 % and a relative standard deviation of 1.0-5.9 %. This work confirmed the feasibility of solvent and monomer regulation synthesis of Fe3O4@CD-MON composites, and revealed the great prospects of magnetic CD-MONs for efficient enrichment of trace estrogens in complex biological samples.

Dissolution-precipitation method concatenated sodium alginate/MOF-derived magnetic multistage pore carbon magnetic solid phase extraction for determination of antioxidants and ultraviolet stabilizers in polylactic acid food contact plastics

Antioxidants and UV stabilizers have some endocrine disrupting effects and liver toxicity. Both types of additives are still widely used in food contact plastics to improve the durability of plastic products. However, efficient and rapid detection of antioxidants and UV stabilizers has been a challenge due to the complexity of the plastic matrix and the low content of antioxidants and UV stabilizers. In this study, a sodium alginate/MOF-derived magnetic multistage pore carbon material (MIL-101(Fe)/SA-CAs) was developed, having the merits of abundant multistage pore structure, large specific surface area, and good magnetic separation properties. Thus, this material was selected as the sorbent for magnetic solid-phase extraction combined with a dissolution-precipitation method for the extraction and purification of antioxidants and UV stabilizers from polylactic acid food contact plastics. The extraction parameters such as sorbent type, sorbent dosage, sample solution pH, ionic strength, sorption time, elution solution type, volume, and time were investigated. Under the optimized conditions, all the analytes determined by UPLC-MS/MS showed good linear range (r > 0.99), detection limit (0.023-3.105 ng g-1), accuracy (70.6-102.3 %), and reproducibility (RSD<9.8 %). Further, the developed method was applied to determine the antioxidants and UV stabilizers in polylactic acid lunch boxes and straws, showing excellent applicability. The results showed that the antioxidants and UV stabilizers were detected in some of the samples, with a maximum detection of antioxidant 1010 at 7297 ng g-1. This study provided a sensitive, efficient, and environmentally friendly method for antioxidants and UV stabilizers in polylactic acid food contact plastics. The ideas for the design of environmentally friendly metal-organic frameworks and biomass composite multifunctional materials would promise in the sample pretreatment field for the emerging contaminants.

Preparation of Fe3O4-Reduced Graphene-Activated Carbon from Wastepaper in the Dispersive Solid-Phase Extraction and UHPLC-PDA Determination of Antibiotics in Human Plasma

In this work, a sorbent was prepared from wastepaper samples enriched with iron oxide particles and graphene oxide and used in the solid phase extraction of antibiotics. The precursor underwent a carbothermal reduction to promote the formation of paramagnetic phases useful for the recovery of the sorbent during the analysis, and to disperse and fix graphene and the iron oxide in a durable way throughout the cellulose structure. Characterizations were carried out to evaluate the composition (Raman, XRD and EDX) and the morphological structure (SEM) of the material. A UHPLC-PDA method was developed for the simultaneous determination of antibiotics from different drug families (carbapenems, fluoroquinolones, β-lactams) using a 120 SB-C 18 poroshell column (50 × 2.1 mm I.D., 2.7 um particle size) and a mobile phase consisting of 10 mM acetate buffer at pH 5 (Line A) and acetonitrile (Line B) both containing 0.1% of triethylamine. A gradient elution was used for the separation of the analytes, while for the quantitative analysis each analyte was determined at its maximum wavelength. Several experiments were carried out to evaluate the influence of different parameters involving the dispersive magnetic solid phase extraction of these analytes. Samples were extracted using 25 mg of sorbent at pH 5 and desorbed in 5 min using methanol. We report herein on some of the outstanding advantages of using carbon-based sorbent, such as lower toxicity, scalability, improved absorption capacity, target selectivity and stability in acidic medium. Moreover, from the results obtained it is evident that, despite the use of some recycled materials, the performances obtained were comparable or even superior to the methods reported in the literature.

Covalent triazine-based frameworks for efficient solid-phase microextraction of phthalic acid esters from food-contacted plastics

Owing to various health threats associated with phthalic acid esters (PAEs), this category of endocrine-disrupting compounds has attracted more and more public scrutiny. However, the efficient preconcentration of PAEs from complex food-contacted plastics still remains challenging. Herein, three covalent triazine-based frameworks (CTFs) were constructed by facile Friedel-Crafts reactions of cyanuric chloride (CC), with triptycene (TPC), fluorene (FL) and 1,3,5-triphenylbenzene (TPB), respectively. Three CTFs were then employed as solid-phase microextraction (SPME) coatings for the extraction of PAEs. Benefiting from the large surface area and high pore volume, the newly-synthesized CC-TPC based SPME method exhibited large enrichment factors (978-2210), low limits of detection (0.027-0.10 ng g ^- 1), satisfactory linear ranges (0.09-20 ng g ^- 1), acceptable repeatabilities (4.3-9.6%) and high relative recoveries (92.0-104.6%).

Simple Synthesis of Fe3O4@-Activated Carbon from Wastepaper for Dispersive Magnetic Solid-Phase Extraction of Non-Steroidal Anti-Inflammatory Drugs and Their UHPLC–PDA Determination in Human Plasma

In the present society, the recycling and reuse of valuable substances are of utmost importance for economic and environmental purposes. At the same time, there is a pressing need to develop new methods to protect the ecosystem from many human activities, including those that have contributed to an ever-increasing presence of pharmaceutical pollutants. In this study, a straightforward approach that applies a magnetic carbon composite for the effective removal of NSAIDs from biological fluids is reported. The composite was produced by recycling wasted handkerchiefs, to provide cellulose to the reactive system and then transformed into carbon via calcination at high temperature. The morphological and structural features of the prepared “Fe3O4@-activated carbon” samples were investigated via thermal analysis, X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. Magnetic solid-state extraction was carried out to reveal the adsorption capabilities of the magnetic carbon composite and then combined with UHPLC–PDA for the determination and quantification of five NSAIDs (furprofen, indoprofen, ketoprofen, flurbiprofen, and indomethacin). The method developed herein proved to be fast and accurate. The adsorbent could be reused for up to 10 cycles, without any decrease in performance; thus, it contributes to an intelligent and sustainable economic strategy projected toward minimal waste generation.

Occurrence and removal characteristics of phthalate esters from bottled drinking water using silver modified roasted date pits

BACKGROUND

This paper aims to investigate the occurrence and removal characteristics of phthalate esters from bottled drinking water using silver modified roasted date pits. Three adsorbents, namely roasted date pits (RODP), silver-modified roasted date pits (S-RODP), and activated carbon (AC) were used to investigate their adsorption characterizations in removing dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), and di-n-octyl phthalate (DNOP) from the collected bottle water samples.

METHODS

The occurrences of the phthalate esters in the collected bottled water samples were carried out at different temperatures (30, 50, and 60 °C), and analyzed using gas chromatography-mass spectrometry analysis - selected ion monitoring. Batch adsorption isotherms were used to study and establish the efficiency of such adsorbents in removing phthalate esters, in which they describe the adsorbent-adsorbate interaction systems. Adsorption efficiency of the various adsorbents was investigated by using different adsorbent masses (0.05 g, 0.10 g, and 0.15 g) and temperature (30 °C, 50 °C, and 60 °C). Different physical and chemical characterizations were studied using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Brunauer-Emmett-Teller (BET) surface area, pore radius, and pore volume.

RESULTS

The results indicated that the most abundant phthalate esters were DMP followed by DEP under 30 °C; however, DNOP was not detected in any of the tested water samples, except for one sample under 30 °C with a concentration of 0.031 μg/mL. The obtained results showed that phthalate esters leaching to the bottled drinking water were affected by storage temperature. The phthalate esters levels were increased with increasing the temperature to 60 °C. It was concluded that the ability of S-RODP for the adsorption of phthalate esters was better than the removal percentage obtained by AC and RODP. The removal percentage was increased from 90 to 99% by increasing the temperature from 30 to 50 °C and then decreased to 92.3% at 60 °C.

CONCLUSION

RODP was successfully used as an effective adsorbent for phthalate esters removal from drinking water. However, S-RODP has the highest removal abilities than other adsorbents due to the newly formed functional groups on its surface.

Improved performance of 3D hierarchical NiAl-LDHs micro-flowers via a surface anchored ZIF-8 for rapid multiple-pollutants simultaneous removal and residues monitoring

In this paper, we report a new type of 3D ZIF-8@NiAl-LDHs micro-flowers material consisting of sandwich-like structured 2D nanopetals (highly compact ZIF-8 film anchored on both sides of petals). ZIF-8 was successfully incorporated into NiAl-LDHs (ZIF-8@NiAl-LDHs) via seeding strategy directed growth of ZIFs on the surface of LDHs nanopetals. The coating of ZIF-8 significantly increased the adsorption ability to organic pollutants and inorganic cation. 3D ZIF-8@NiAl-LDHs with excellent enrichment and filtration properties has been exploited for the application in water purification, and exhibit superior high adsorption rate and adsorption efficiency of organic (nonsteroidal anti-inflammatory drugs: ketoprofen, flurbiprofen, indometacin and ibuprofe; anionic dyes: congo red, orange g; cationic dyes: methylene blue, rhodamine b) and inorganic cation (Cu²⁺, Pb²⁺) residues due to their novel hierarchical and submicroscopic structures. Further, 3D ZIF-8@NiAl-LDHs as filter membrane to extraction four kind of trace anti-inflammatory drugs followed by direct quantification detection of targets with HPLC was demonstrated. The validated method was successfully applied for analysis of four anti-inflammatory drugs in environmental water and human urine samples. This work provided a feasible way to design and construct purification materials for wastewater treatment and contaminant detection.

Preparation, surface functionalization and application of Fe3O4 magnetic nanoparticles

This paper reviews recent developments in the preparation, surface functionalization, and applications of Fe₃O₄ magnetic nanoparticles. Especially, it includes preparation methods (such as electrodeposition, polyol methods, etc.), organic materials (such as polymers, small molecules, surfactants, biomolecules, etc.) or inorganic materials (such as silica, metals, and metal oxidation/sulfide, functionalized coating of carbon surface, graphene, etc.) and its applications (such as magnetic separation, protein fixation, magnetic catalyst, environmental treatment, medical research, etc.). In the end, some existing challenges and possible future trends in the field were discussed.

Assembling 3D hierarchical hollow flower-like Ni@N-doped graphitic carbon for boosting simultaneously efficient removal and sensitive monitoring of multiple sulfonamides

The excessive accumulation of sulfonamides (SAs) drugs makes it imperative to develop novel materials for boosting simultaneously efficient removal and precise monitoring of multiple SAs. Herein, three-dimensional hollow flower-like Ni@nitrogen-doped graphitic carbon (3DHFNi@NGC) was designed/fabricated via a facile one-pot hydrothermal route and subsequent pyrolysis. The resultant 3DHFNi@NGC exhibits a unique 3D hollow hierarchical architecture assembled by a layer-by-layer interlacing of corrugated nanosheets subunits, thereby affording numerous interconnected channels, available internal/external surfaces as well as suitable interior cavities. By virtue of its special architecture and in-situ generated N-doped graphitic carbon along with good magnetism, the 3DHFNi@NGC demonstrates superior sorption performance towards SAs, accompanied by high total saturated adsorption capacity, fast sorption rate and easy magnetic recycling. It is noteworthy that as-constructed 3DHFNi@NGC also exhibits high-sensitive/simultaneous detection of trace multiple SAs combined high performance liquid chromatography (HPLC), together with a low detection limit (0.035-0.071 ng mL^-1) and a broad linear range (0.2-100 ng mL^-1) as well as high enrichment factors (252 < EFs < 291). These indicate that the smart 3DHFNi@NGC could be a promising candidate for the synchronous remediation and sensitive detection of multiple SAs in aqueous systems, presenting a viable option for sewage treatment and water quality monitoring.

Fabrication of WO2/W@C core-shell nanospheres for voltammetric simultaneous determination of thymine and cytosine

Pomegranate-like multicore WO₂/W nanocrystals wrapped with layers of multiporous carbon were fabricated via carbonization of a copper(II)-organic framework host and a tungsten-based polyoxometalates guest, and subsequent etching off the metallic copper. The WO₂/W@C core-shell nanospheres were employed to modify an electrode for the analysis of the DNA bases thymine (T) and cytosine (C) by differential pulse voltammetry. The WO₂/W@C exhibited strongly increased oxidation signal of T and C. Under optimized conditions, the enhanced peak current represented excellent analytical performance for determination of T and C. This is attributed to the synergic effects of the porous multicore-shell microstructure and the use of tungsten-based materials with their excellent electrocatalytic activity for T and C, with typical peaks voltages near 1.26 V and 1.44 V. The calibration plots for T and C extend from 1 to 4000 μM and from 1 to 3000 μM, respectively, and both detection limits are 0.2 μM. The method was successfully applied to the determination of T and C in spiked blood and urine samples, and the recoveries are form 97.3 to 105.0%. Graphic abstractCore-shell nanospheres of type WO2/W-carbon were prepared for highly sensitive simultaneous voltammetric determination of thymine and cytosine.

Novel functionalized magnetic ionic liquid green separation technology coupled with high performance liquid chromatography: A rapid approach for determination of estrogens in milk and cosmetics

Several magnetic ionic liquids (MILs), [P_6,6,6,14⁺][FeCl₄^-], [P_6,6,6,14⁺]₂[MnCl₄^2-], [P_6,6,6,14⁺]₂[CoCl₄^2-] and [P_6,6,6,14⁺]₂[NiCl₄^2-] were synthesized and applied for the extraction of six estrogens (estrone, estradiol, 17-α-hydroxyprogesterone, chloromadinone 17-acetate, megestrol 17-acetate and medroxyprogesterone 17-acetate) in dispersive liquid-liquid microextraction (DLLME). The [CoCl₄^2-]-based MIL was selected as extraction solvent for the separation and concentration of estrogens from milk and cosmetics due to its visual recognition, no sign of hydrolysis, solution acquisition easier and the highest extraction capacity. In addition, the [CoCl₄^2-]-based MIL with low UV absorbance allows direct analysis of the extraction solvent by HPLC-UV. The influence of the mass of MIL, extraction time, salt concentration, and the pH of the sample solution was investigated to obtain optimized extraction efficiency. Besides, extraction conditions including salt concentration, mass of MIL and extraction time were further optimized by the Box-Behnken design through the response surface method. Under optimized conditions, the limits of detection (LODs) of all estrogens were ranged from 5 ng mL^-1 to 15 ng mL^-1. The recoveries ranging from 98.5% to 109.3% in milk and from 96.3% to 111.4% in cosmetics were also studied, respectively. Furthermore, the proposed method were statistically compared with the reported conventional IL-DLLME method and the National standard methods of food safety and cosmetics. The experimental results showed that the functionalized MIL could successfully applied for extraction, separation and pretreatment of estrogens in milk and cosmetics.

Ultrasound combined with manganese-oxide nanoparticles loaded on activated carbon for extraction and pre-concentration of thymol and carvacrol in methanolic extracts of Thymus daenensis, Salvia officinalis, Stachys pilifera, Satureja khuzistanica, and mentha, and water samples

A dispersive micro solid-phase extraction (DMSPE) technique was developed using manganese-oxide nanoparticles loaded on activated carbon (Mn₃O₄-NPs-AC) as an effective sorbent combined with ultrasound for the extraction and determination of a trace amount of thymol and carvacrol in methanolic extracts of Thymus daenensis, Salvia officinalis, Stachys pilifera, Satureja khuzistanica and mentha, and water samples.

Dispersive micro-solid phase extraction based on Fe3O4@SiO2@Ti-MOF as a magnetic nanocomposite sorbent for the trace analysis of caffeic acid in the medical extracts of plants and water samples prior to HPLC-UV analysis

In this work, Fe₃O₄@SiO₂@Ti-MOF-NCs, as an efficient sorbent, have been synthesized in a laboratory and utilized for extracting CA in the medical extracts of plants and water samples before their analysis by HPLC.