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This work proposes the miniaturization and modification of the QuEChERS strategy using different large pore mesostructured silicas, non-modified and modified with amino groups (NH 2 ), as dispersive clean-up sorbents for multi-component extraction of 21 pyrrolizidine alkaloids from different aromatic herbs, combined with ultra-high performance liquid chromatography coupled to tandem mass spectrometry analysis. The procedure was miniaturized by reducing the amounts of sample (0.2 g), solvents (2 mL), clean-up sorbents (25 mg sorbent + 150 mg MgSO 4 ) and partitioning salts (0.65 g) employed. Best results were achieved using mesostructured silicas (LP-MS-NH 2 ) than conventional PSA. The method was validated (overall recoveries 73-105%) and applied to the analysis of 17 samples. All the samples were contaminated with PAs (average concentration 262 µg/Kg). Thyme and basil samples were the most contaminated, whereas rosemary was the least. Lasiocarpine, senecivernine N-oxide and europine N-oxide were the main PAs that contributed to their contamination., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In this work, Hexagonal Mesoporous Silica (HMS) and Santa Barbara Amorphous-15 (SBA-15) mesostructured silicas were synthesized and functionalized with sulfonic acid groups. The materials (HMS-SO3− and SBA-15-SO3−) were evaluated as strong cation exchange sorbents for sample extract clean-up, by solid phase extraction (SPE) and dispersive solid phase extraction, to determine atropine (At) and scopolamine (Sc) in commercial culinary aromatic herbs. Under optimized conditions, 0.25 g of sample was subject to solid−liquid extraction with acidified water (pH 1.0), and good recovery percentages were achieved for At and Sc using 75 mg of HMS-SO3− in SPE as the clean-up stage, prior to their determination by HPLC-MS/MS. The proposed method was validated in a thyme sample showing recoveries in the range of 70−92%, good linearity (R2 > 0.999), adequate precision (RSD ≤ 14%) and low limits (MDL 0.8−2.2 µg/kg and MQL 2.6−7.2 µg/kg for both analytes). Sixteen aromatic herbs samples (dried thyme, basil and coriander leaves) were analysed and At was found in fourteen samples over an interval of <5−42 μg/kg, whereas Sc was found in three of the sixteen samples studied (between <5−34 μg/kg). The amount of At and Sc found in some analysed samples confirms the importance of setting maximum levels of At and Sc in culinary aromatic herbs.

In this work a new method for the determination of 5-hydroxymethylfurfural (HMF) in cereal and insect bars has been developed and validated. The method consisted of a solid-liquid extraction (SLE) followed by a solid phase extraction (SPE), employing functionalized mesostructured silica as sorbent, and prior to high-performance liquid chromatography coupled to mass spectrometry analysis (HPLC-MS/MS). Mesostructured silica with a large pore (SBA-15-LP) functionalized with aminopropyl- groups (SBA-15-LP-NH 2 ), octyl- groups (SBA-15-LP-C8) and bifunctionalized with both organic ligands (SBA-15-LP-C8-NH 2 ) were prepared, characterized and tested for this purpose. The optimal conditions showed that the best extraction solvent was water acidified with HCl (pH 1.0) and the best material for SPE was SBA-15-LP-NH 2 (recoveries near 100%). Results were compared with other analogous commercial sorbent (Discovery® DSC-NH 2 ), evaluated under similar conditions, and SBA-15-LP-NH 2 sorbent showed better recoveries than the commercial one (62 ± 1%). The developed method was validated and good detection and quantification limits (MDL: 11 µg kg -1 and MQL: 38 µg kg -1 ), good precision in terms of repeatability and within-laboratory reproducibility (RSD < 8%) and good accuracy (recoveries between 99-102%) were obtained. The method was successfully applied to the determination of HMF in different samples of cereals and insect bars. In all the samples analysed, high concentrations of HMF (ranging from 336 to 962 mg kg -1 ) have been found., Competing Interests: Declaration of Competing Interest The authors have declared no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A wormhole-like mesostructured silica was synthesized and modified with octadecylsilane (C18) groups. The resulting hybrid material (HMS-C18) was characterized and evaluated as sorbent for simultaneous extraction of 20 polyphenols from mixed fruit-vegetable juices and smoothies by dispersive solid-phase extraction (dSPE). The samples were first subjected to solvent extraction followed by dSPE procedure. The extraction step was optimized and combined with a reversed-phase ultra-high-performance liquid chromatography method coupled to ion-trap tandem mass spectrometry (UHPLC-IT-MS/MS), which was also optimized. HMS-C18 showed high potential to extract and purify the target analytes, being more effective than commercial C18 amorphous silica. The proposed method was validated for both samples, obtaining average recoveries from 57% to 99% with relative standard deviations lower than 9%. Its applicability in the analysis of commercial mixed fruit-vegetable juices and smoothies revealed mainly contents of rutin, 4-hydroxybenzoic acid, chlorogenic acid, epicatechin, caffeic acid, and naringin in the samples analyzed.

Two novel periodic mesoporous organosilica materials were synthesized with a neutral phenylene-bridged ligand, 1,4-bis(trimethoxysilylethyl)benzene, one of them using tetraethyl orthosilicate as additional silica source (PMO-TMSEB-1 and PMO-TMSEB-2). A third material was also synthesized with 1,4-bis(triethoxysilyl)benzene ligand (PMO-TESB-1) which use has scarcely been reported. The three materials were evaluated as solid-phase extraction (SPE) sorbents for the off-line extraction of a mixture of seven drugs of different nature (duloxetine, terbutaline, econazole, propranolol, verapamil, metoprolol, and betaxolol) from water samples. Subsequent simultaneous enantiomeric analysis by CE, using sulfated-β-cyclodextrin (2% w/v) dissolved in a 25 mM phosphate buffer (pH 3.0) and a voltage of -20 kV (negative polarity) was carried out. Enantiomeric resolutions ranging from 2.4 to 8.5 were obtained in an analysis time of 16 min. After optimization of SPE parameters, it was shown that using just 100 mg of PMO-TESB-1 as sorbent, a preconcentration factor of 400 with 200 mL solution was achieved, allowing recoveries between 80.5 and 103.1% (except for terbutaline), with good repeatability (% RSD = 2-8 %, n = 5). Analytical characteristics of the method were evaluated in terms of precision, linearity and accuracy with method quantitation limits between 5.6 and 21.9 μg/L. The developed method was applied to the analysis of spiked wastewater samples collected in different treatment plants, with recoveries between 73.9 and 102.9% except for econazole with recovery values ranging between 58.5 and 72.4%., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two novel materials based on periodic mesoporous organosilica (PMO) with cationic amine-bridged ligands, (styrylmethyl)bis(triethoxysilylpropyl)ammonium chloride (PMO-STPA) and bis(3-triethoxysilylpropyl)amine (PMO-TEPA), were synthesized in this work to obtain materials with reverse-phase/strong anionic exchange mixed-mode or strong anionic exchange retention mechanism, respectively. The resulting materials were comprehensively characterized and showed functionalization with cationic amine-bridged ligands, and values of surface areas characteristic of mesoporous materials (higher than 100m 2 /g). These materials were evaluated for the off-line solid-phase extraction (SPE) of a mixture of six phenoxy acid herbicides (fenoprop, mecoprop, dichlorprop, 2-(4-chlorophenoxy)propionic acid (4-CPPA), 2-(3-chlorophenoxy)propionic acid (3-CPPA), 2-phenoxypropionic acid (2-PPA)) from water samples previous to their analysis by CE with diode-array detection using a dual chiral selector system (20mM of heptakis(2,3,6-tri-O-methyl)-β-CD (TM-β-CD) and 7mM of (2-hydroxypropyl)-β-CD (HP-β-CD) dissolved in 50mM phosphate buffer, pH 7.0) which enabled the simultaneous enantiomeric separation of the six phenoxy acid herbicides in 11min. SPE parameters were optimized and recoveries obtained for PMO-STPA and PMO-TEPA sorbents were compared. Under the optimized conditions, it was demonstrated that using 100mg of PMO-STPA sorbent, a maximum preconcentration factor (PF) of 1500 was achieved with 750mL of standard solution, allowing recoveries between 75.5 and 112.2%, with good repeatability (RSD=1.9-8.7%, n=6). Analytical characteristics of the method were evaluated in terms of precision, linearity and accuracy with method quantitation limits (MQL) between 0.4 and 14.3μg/L. The developed method was applied to the analysis of river samples and effluents from wastewater treatment plants, with recoveries ranging from 78.3 to 107.5%., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A method for simultaneous separation and determination of four enantiomeric pairs of β-blockers in waters by chiral CE has been developed. Off-line SPE was employed using functionalized ordered mesoporous silica as sorbent. Separation by CE was achieved using a BGE composed by methylated-β-CD (1.25% w/v) dissolved in a 50 mM phosphate buffer (pH 2.5) and 30°C, with good chiral resolution for all enantiomers. Mesoporous silica functionalized with octadecyl groups (denoted SBA15-C18) was prepared by a postsynthesis method and applied for the preconcentration of atenolol, propranolol, metoprolol, and pindolol enantiomers in waters by off-line SPE. Under optimized conditions, a preconcentration factor of 300 was achieved, employing 100 mg of SBA15-C18 as sorbent, with recoveries between 96 and 105% in tap water and good repeatability (% RSD = 7-11%, n = 6). Commercial C18 amorphous silica (ExtraBond R C 18 ) was also tested as sorbent for SPE, but results revealed better extraction capacity with higher recoveries for the SBA15-C18 material. The analytical characteristics of the off-line SPE-chiral CE method were evaluated, showing good precision, linearity, and accuracy with method quantification limits between 5.3 and 13.7 μg/L for all enantiomers. The SBA15-C18 material allowed the extraction of four enantiomeric pairs of β-blockers spiked in tap water, river water, and ground water with recoveries between 58 and 105%., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A SBA-15 type mesoporous silica was synthesized and bi-functionalized with octadecylsilane (C18) or octylsilane (C8), and sulfonic acid (SO 3 - ) groups in order to obtain materials with reversed-phase/strong cation-exchange mixed-mode retention mechanism. The resulting hybrid materials (SBA-15-C18-SO 3 - and SBA-15-C8-SO 3 - ) were comprehensively characterized. They showed high surface area, high pore volume and controlled porous size. Elemental analysis of the materials revealed differences in the amount of C18 and C8. SBA-15-C18-SO 3 - contained 0.19mmol/g of C18, while SBA-15-C8-SO 3 - presented 0.54mmol/g of C8. The SO 3 - groups anchored to the silica surface of the pore walls were 0.20 and 0.09mmol/g, respectively. The bi-functionalized materials were evaluated as SPE sorbents for the multi-residue extraction of 26 veterinary drug residues in meat samples using ultra-high-performance liquid chromatography coupled to mass spectrometry detector (UHPLC-MS/MS). Different sorbent amounts (100 and 200mg) and organic solvents were tested to optimize the extraction procedure. Both silicas showed big extraction potential and were successful in the extraction of the target analytes. The mixed-mode retention mechanism was confirmed by comparing both silicas with SBA-15 mesoporous silica mono-functionalized with C18 and C8. Best results were achieved with 200mg of SBA-15-C18-SO 3 - obtaining recoveries higher than 70% for the majority of analytes., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A new procedure for the determination of 12 naturally occurring hormones and some related synthetic chemicals in milk, commonly used as growth promoters in cattle, is reported. The method is based on liquid-liquid extraction followed by solid-phase extraction (SPE) using a new one-pot synthesized ordered mesoporous silica (of the SBA-15 type) functionalized with octadecyl groups (denoted as SBA-15-C18-CO) as reversed-phase sorbent. The analytes were eluted with methanol and then submitted to HPLC with diode array detection. Under optimal conditions, the method quantification limit for the analytes ranged from 0.023 to 1.36μg/mL. The sorbent affored the extraction of estrone, 17β-estradiol, estriol, progesterone, hexestrol, diethylstilbestrol, 4-androstene-3,17-dione, ethinylestradiol, 17α-methyltestosterone, nandrolone, prednisolone and testosterone with mean recoveries ranging from 72% to 105% (except for diethylstilbestrol) with RSD<11%. These results were comparable and, in some cases, even better than those obtained with other extraction methods, therefore SBA-15-C18-CO mesoporous silica possess a high potential as a reversed-phase sorbent for SPE of the 12 mentioned endocrine disrupting compounds in milk samples., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In this work, two mesoporous silicas functionalized with C18 groups (SM-C18 and SBA-15-C18) have been synthesized for their evaluation as stationary phases in SPE for the extraction and preconcentration of seven steroid hormones (estrone, estradiol, estriol, ethinyl estradiol, diethylstilbestrol, testosterone, and progesterone ) from milk. The characterization of both materials by diverse techniques such as transmission electron microscopy, SEM, thermogravimetric analysis, X-ray diffraction, and adsorption-desorption isotherms showed that the mesoporous silicas had a high surface area, high pore volume, and a homogeneous distribution of the pores and that both silicas presented a similar degree of functionalization. An analytical methodology for the simultaneous separation of the seven selected steroids by HPLC-DAD was developed. Both silicas were evaluated as stationary phases in SPE for the extraction of the steroid hormones from milk. This HPLC-DAD method was applied to the analysis of all extracts obtained in the SPE experiments, showing that from the two synthesized mesoporus silicas, SBA-15-C18 silica enabled the extraction of the seven compounds with recoveries between 88 and 108% for all except for estriol, for which a recovery of 62% was obtained. The analytical characteristics of this methodology were evaluated, showing good precision and linearity (R2 > 0.994) for all analytes. The comparison of the results obtained with this silica and those obtained with commercial C18 particles and with some other commercial cartridges usually employed in the extraction of steroids showed that SBA-15-C18 silica was able to extract the seven steroids with higher recovery values., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, a mesoporous silica has been chemically modified with 5-mercapto-1-methyl-1-H-tetrazol using the homogeneous route (MTTZ-HMS). This synthetic route involved the reaction of 5-mercapto-1-methyl-1-H-tetrazol with 3-chloropropyltriethoxysilane, prior to immobilization on the support. The resulting material has been characterized and employed as solid phase extractant for Pb(II). The effect of several variables (stirring time, pH, temperature, metal concentration, presence of other metals) has been studied using batch and column techniques. In batch experiments, 15 min stirring time, 55 degrees C and pH 8 were the optimal conditions for Pb(II) adsorption. In column experiments, sorption was quantitative for 1000 mL of 2.41 x 10(-4 )mM of Pb(II) solution and adsorbed ions were eluted out by 5 mL of 1 M HCl (preconcentration factor of 200). Spiked tap water was used for the preconcentration and determination of Pb(II) by flame atomic absorption spectrometry, and a 100% recovery was obtained. The LOD and LOQ values of the proposed method were found to be 3.52 x 10(-3) and 4.20 x 10(-3 )mM, respectively. The RSD for three preconcentration experiments was found to be

This work focuses on the development of a hybrid material based on SBA-15 silica with a molecularly imprinted polymer (MIP), using spiramycin (SPI) as a template, for use as sorbent in solid-phase extraction (SPE). Characterization techniques such as nitrogen gas adsorption–desorption isotherms, infrared spectroscopy and scanning electron microscopy confirmed the structure and properties of the SBA-15@MIP-SPI material. SPE conditions using SBA-15@MIP-SPI as sorbent were optimized, which allowed us to demonstrate the high selectivity and adsorption capacity of SPI on the synthesized material. The best conditions were 50 mg of sorbent, loading with 1 mL of standard solution or sample of cow milk previously extracted in acetonitrile and eluting with 3 mL of methanol with 1% acetic acid. After the optimization process, the material demonstrated recovery percentages of 81 ± 3% in SPI standard solutions and showed its potential in cow milk samples (71 ± 6%). The novelty of the research consists of the combination of MIPs with SBA-15, which could offer important advantages in terms of specific surface area and porous structure, thus improving performance and reducing the amount of sorbent compared to other traditional methods. [ABSTRACT FROM AUTHOR]

In the last years, sample preparation has been playing an important role in the analysis of xenobiotics in complex matrices, such as food samples. Recent advances in the development of new materials, such as ordered mesoporous silicas (OMSs) and other sol–gel silica-based materials, have gained increasing research interest in sample preparation and analytical chemistry due to their desirable characteristics and advantages versus traditional and commercial sorbents, since they enhance the analytical performance of many existing techniques or allow new ones to be developed. The aim of this review is to provide an overview with the most relevant achievements in the preparation and functionalization of OMSs and other sol–gel organic–inorganic hybrid silicas, and to give some recent examples from the last six years (from 2010 to 2016) regarding the analytical applications of these materials in sample preparation and extraction of xenobiotics from food products, including beverages and drinking water samples. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mesoporous silicas were examined as sorbents for solid-phase extraction of 17β-estradiol in waters. [•] SBA-C18 had the highest adsorption affinity towards 17β-estradiol and under optimized conditions. [•] 17β-Estradiol was determined by HPLC-DAD in drinking water with high recoveries and precision. [Copyright &y& Elsevier]

Tropane alkaloids (TAs) are natural toxins produced by different plants, mainly from the Solanaceae family. The interest in TAs analysis is due to the serious cases of poisoning that are produced due to the presence of TA-producing plants in a variety of foods. For this reason, in recent years, different analytical methods have been reported for their control. However, the complexity of the matrices makes the sample preparation a critical step for this task. Therefore, this review has focused on (a) collecting the available data in relation to the occurrence of TAs in foods for human consumption and (b) providing the state of the art in food sample preparation (from 2015 to today). Regarding the different food categories, cereals and related products and teas and herbal teas have been the most analyzed. Solid–liquid extraction is still the technique most widely used for sample preparation, although other extraction and purification techniques such as solid-phase extraction or QuEChERS procedure, based on the use of sorbents for extract or clean-up step, are being applied since they allow cleaner extracts. On the other hand, new materials (molecularly imprinted polymers, mesostructured silica-based materials, metal–organic frameworks) are emerging as sorbents to develop effective extraction and purification methods that allow lower limits and matrix effects, being a future trend for the analysis of TAs. [ABSTRACT FROM AUTHOR]

[Display omitted] • New chemically modified membrane-based sorbent for solid-phase extraction. • First use of FGM functionalised with SBA-15-NH 2 for macrolides isolation. • The membrane-SPE-HPLC-MS/MS method provided low limits and good recoveries. • The optimized method was successfully applied to macrolides analysis in eggs. Macrolides are a group of high-spectrum antibiotics used to treat animal ailments, sometimes these drugs can appear as residues in animal foods such as eggs, which must be controlled as required by the European Union. Therefore, in this paper a methodology based on solid–liquid extraction followed on the application of a new membrane-solid-phase extraction (membrane-SPE) was developed and validated for the extraction and purification of five macrolide antibiotics such as spiramycin (SPI), erythromycin (ERY), roxithromycin (ROX), josamycin (JOS) and tylosin (TYL), in egg samples for their analysis by high-performance liquid chromatography coupled to mass spectrometry analysis (HPLC-MS/MS). The newly synthesised membrane-based sorbent consisted of a fibreglass membrane chemically modified with silica SBA-15 type functionalised with amino groups (FGM-SBA-15-NH 2). The optimal conditions for membrane-SPE on eggs were determined using a three-factor, three-level Box Behnken design (BBD). The conditions obtained were by loading with 4 mL of water and eluting with 3 × 2.5 mL of MeOH with ammonia solution (0.5 %, v/v). The methodology was validated according to Regulation (EU) 2021/808 showing good selectivity, linearity (R2 ≥ 0.993), low limits (MQL 1.1–2.1 ng/g, MDL 0.3–0.6 ng/g), acceptable decision limit for confirmation (CCα), good accuracy (recoveries 85–100 %) and an adequate precision (RSD ≤ 16 %). The FGM-SBA-15-NH 2 proved to be reproducible in different batches and reusable around 70 times. Finally, the validated method was successfully applied to fourteen egg samples detecting SPI in one hen egg sample and JOS and ROX in one quail egg sample. The proposed methodology introduces a groundbreaking membrane-SPE approach, addressing limitations in conventional SPE methods. The use of functionalised silica to chemically modify FGM significantly improves its textural properties, allowing the simultaneous extraction and purification of macrolide antibiotics from egg samples. [ABSTRACT FROM AUTHOR]

In recent years, health authorities have become increasingly concerned about preventing consumer exposure to opium alkaloids present in Papaver somniferum L. poppy seeds. In this study, a simple, rapid and efficient method has been optimised to determine all main opioids in poppy seeds (morphine, codeine, thebaine, papaverine, noscapine and oripavine) by UHPLC-QqQ-MS/MS. For this purpose, solid-liquid extraction (SLE) of samples was optimised and six magnetic adsorbent materials with a core of Fe3O4 coated with amorphous and mesostructured silica, both functionalised with octadecyl-silane or octyl-silane were characterised and evaluated for magnetic solid-phase extraction (MSPE). The material with the best results was non-functionalised mesostructured silica and, with it, the MSPE procedure was optimised. This method was validated and used to quantify six opioids in 14 edible seed samples (eleven poppy seeds and three seed mixes). Considerable amounts were found (1.5–249.0 mg/kg morphine, <0.2 µg/kg–45.8 mg/kg codeine, <2.4 µg/kg–136.2 mg/kg thebaine, <0.2 µg/kg–27.1 mg/kg papaverine, <0.2 µg/kg–108.7 mg/kg noscapine and <240 µg/kg–33.4 mg/kg oripavine), exceeding maximum limits established in some EU countries and the reference level of morphine in the EU. Furthermore, in some commercial samples for human consumption, inadequate labelling was found because significant amounts of alkaloids were detected even though Papaver rhoeas L. seeds were declared on the product label. [ABSTRACT FROM AUTHOR]

Insect-based products are novel foods (NF) that merit careful study. For this reason, in this work a method has been developed for the simultaneous analysis of four food processing contaminants (FPC), acrylamide (AA), 5-hydroxymethylfurfural, (HMF), 5-methylfurfural (MF) and furfural (F), in insect-based products (bars, crackers and flours) by high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (HPLC-QqQ-MS/MS). The method consisted of a solid-liquid extraction (SLE) with acidified water, followed by solid-phase extraction (SPE), using 100 mg of a sorbent based on mesostructured silica with a large pore functionalized with amino groups (SBA-15-LP-NH2). The analytical method was properly optimized and validated in a representative bar sample of pineapple & coconut with cricket flour (Ins-B-Pine-Coco) showing good accuracy, with recoveries ranging from 70–101% for the four analytes and adequate precision (RSD < 9%). Good linearity (R2 ≥ 0.995) and low method quantification limits for AA (between 1.3–1.4 µg/g), F (between 7.9–8.8 µg/g), MF (between 3.1–6.5 µg/g) and HMF (between 1.5–3.3 µg/g) were also obtained in all samples studied. The proposed method was successfully applied in eleven insect-based foods. Results revealed that insect-based bars can be a good alternative to traditional cereal bars to reduce dietary exposure to HMF; but, in order to reduce the exposure to AA, alternative formulations must be evaluated in the design of innovative insect-based crackers. [ABSTRACT FROM AUTHOR]

A novel method was developed and applied to the determination of the most representative tropane alkaloids (TAs), atropine and scopolamine, in gluten-free (GF) grains and flours by HPLC-MS/MS. Accordingly a suitable sample treatment procedure based on solid-liquid extraction (SLE) and followed by strong cation-exchange solid-phase extraction (SCX-SPE) was optimized. SBA-15 mesostructured silica functionalized with sulfonic acids was evaluated as sorbent. The proposed method was fully validated in sorghum flour showing good accuracy with recoveries in the range of 93–105%, good linearity (R2 > 0.999) and adequate precision (RSD < 20%). Low method quantification limits (MQL) were obtained (1.5 and 2.4 µg/kg for atropine and scopolamine, respectively) and no matrix effect was observed thanks to the extraction and clean-up protocol applied. The method was applied to 15 types of GF samples of pseudocereals (buckwheat, quinoa and amaranth), cereals (teff, corn and blue corn, sorghum and millet) and legumes (red and green lentil, chickpea and pea). Atropine was found above the MQL in eight of them, with values between 7 and 78 µg/kg, while scopolamine was only found in teff flour, its concentration being 28 µg/kg. The method developed is an interesting tool for determining TAs in a variety of samples of GF grains and flours. [ABSTRACT FROM AUTHOR]

Hybrid mesostructured silicas with wormhole-like pore structure were synthesized and bi-functionalized with n-octyl (C8) and quaternary ammonium (NR4+) groups to obtain new sorbent materials for dispersive solid-phase extraction (dSPE) of polyphenols. Due to their nature of being both a reversed-phase and a strong anion-exchanger, the materials display mixed-mode retention mechanism. During the synthesis, the functionalization conditions were varied to obtain materials with different functionalization degree. The resulting materials (denoted as HMS-RPC8-SAX-1, HMS-RPC8-SAX-2 and HMS-RPC8-SAX-3) show high surface area, wormhole-like framework and controlled pore size. They were evaluated for multicomponent extraction of 22 polyphenols, including phenolic acids, flavonoids and stilbenes, from spiked juice samples. The sample extracts were analyzed by ultra-high performance liquid chromatography coupled to ion-trap tandem mass spectrometry. The adsorption capability, the amount of sorbent, the eluent and the elution volume were optimized. Best performance was achieved by using HMS-RPC8-SAX-2, which is the material with the highest fraction of NR4+ groups. This material has a large extraction capability and provides high recovery values of the target analytes (70-101%) as a result of its hydrophobic and anion-exchange interactions. The detection limits for polyphenols in juice range from 1 to 560 ng mL−1.Schematic presentation of dispersive solid-phase extraction of polyphenols from juice samples using a novel sorbent based on the bi-functionalization of mesostructured silica with n-octyl and quaternary ammonium groups, followed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) analysis. Due to the sorbent nature of being both a reversed-phase and strong anion-exchanger, the material displays mixed mode retention mechanism that improves its extraction capability. [ABSTRACT FROM AUTHOR]

A quick, sensitive and selective analytical reversed-phase method using ultra-high performance liquid chromatography coupled to an ion-trap mass spectrometry detector (UHPLC-IT-MS/MS) was employed for the simultaneous determination of nine phenolic compounds (PCs) in strawberry tree (SBT) berries. The sample treatment included a solid-liquid extraction followed by a dispersive solid-phase extraction (dSPE) procedure using a hybrid large pore mesoporous silica (LP-MS) functionalized with β-cyclodextrin (β-CD) as sorbent material. For this purpose, the initial synthesized LP-MS was modified with β-CD following three different synthetic routes, obtaining three new functionalized materials (denoted LP-MS-β-CD-R1, LP-MS-β-CD-R2 and LP-MS-β-CD-R3). All synthesized materials were comprehensively characterized, showing excellent textural properties, and they were also tested as sorbent materials in the extraction of PCs by comparison of SPE and dSPE procedures. The LP-MS-β-CD-R2 as sorbent material in the dSPE procedure showed the best potential to extract and purify the target PCs, being more effective than the other materials and compared with the SPE procedure. The performance of the proposed dSPE-UHPLC-IT-MS/MS method was validated in terms of selectivity, linearity, LOD, LOQ, trueness, precision, and matrix effect, achieving good analytical method performance and demonstrating its feasibility and practicality for the quantification of PCs in SBT fruits. The analysis of the investigated SBT berries revealed, mainly, high contents of arbutin reaching concentrations up to 5979 µg/g dry weight, followed by catechin (661 µg/g dry weight). Arbutin was, undoubtedly, the major PC determined in all SBT berry samples analyzed, being the most prominent and showing a high concentration compared to that of other polyphenols determined in other red berries. [Display omitted] • Hybrid large pore mesoporous silica-β-cyclodextrin sorbent for polyphenols extraction. • Better performance of dSPE than SPE being a more environmentally friendly methodology. • Higher extraction efficiency of LP-MS-β-CD-R2 with recoveries between 104 % and 113 %. • Selective determination of polyphenols from strawberry tree berries by UHPLC-IT-MS/MS. • Strawberry tree berries are an excellent source of arbutin and catechin. [ABSTRACT FROM AUTHOR]

A quick, sensitive and selective analytical reversed-phase multi-residue method using ultra-high performance liquid chromatography coupled to an ion-trap mass spectrometry detector (UHPLC-IT-MS/MS) operating in both positive and negative ion mode was developed for the simultaneous determination of 23 veterinary drug residues (β-blockers, β-agonists and Non-Steroidal Anti-inflammatory Drugs (NSAIDs)) in meat samples. The sample treatment involved a liquid-solid extraction followed by a solid-phase extraction (SPE) procedure. SBA-15 type mesoporous silica was synthetized and modified with octadecylsilane, and the resulting hybrid material (denoted as SBA-15-C18) was applied and evaluated as SPE sorbent in the purification of samples. The materials were comprehensively characterized, and they showed a high surface area, high pore volume and a homogeneous distribution of the pores. Chromatographic conditions and extraction procedure were optimized, and the method was validated according to the Commission Decision 2002/657/EC. The method detection limits (MDLs) and the method quantification limits (MQLs) were determined for all the analytes in meat samples and found to range between 0.01–18.75 μg/kg and 0.02–62.50 μg/kg, respectively. Recoveries for 15 of the target analytes ranged from 71 to 98%. In addition, for comparative purpose SBA-15-C18 was evaluated towards commercial C18 amorphous silica. Results revealed that SBA-15-C18 was clearly more successful in the multi-residue extraction of the 23 mentioned analytes with higher recovery values. The method was successfully tested to analyze prepacked preparations of mince bovine meat. Traces of propranolol, ketoprofen and diclofenac were detected in some samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fast and more eco-friendly methodology to control opium alkaloids in food products. • First validated methodology for opium alkaloid analysis in biscuits and sponge cakes. • SBA-15 was used for the solid-phase extraction to avoid matrix interferences. • Ultrasound-assisted extraction allowed solvent volume and extraction time reduction. • Morphine was detected in all samples studied below the legislated maximum limits. Food products containing poppy seeds are increasingly consumed. These seeds may be contaminated with opium alkaloids (OAs) from the latex of the plant (Papaver somniferum L.), which may present a health hazard to the consumer. Therefore, the aim of this work was to develop an efficient, fast and environmentally friendly methodology to control OAs in biscuits and sponge cake products by analysis with liquid chromatography coupled to a triple quadrupole tandem mass detector (HPLC-MS/MS). For this purpose, the ultrasound-assisted extraction (UAE) step was optimised using a 5-variable full factorial design at two levels, obtaining lower solvent volume and time than with other classical methods. Then, a solid phase extraction (SPE) was used to remove matrix effects. A commercial material (HLB) and two silica synthesised materials (HMS and SBA-15) were evaluated and optimised, selecting SBA-15 (50 mg). Finally, the method was validated and applied to real samples, showing morphine concentrations in 5 of 7 products but below the maximum permitted limit. [ABSTRACT FROM AUTHOR]

Mesoporous silica, bi-functionalized with octadecyl and aminopropyl groups was prepared and characterized. The adsorption capacity of the prepared silica for a mixture of twelve endocrine disrupting compounds in water was evaluated by solid-phase extraction and compared with a commercial phase. Analytes were determined by high performance liquid chromatography. Under optimized conditions, the material showed recoveries near 100% with standard deviations between 3 and 10%, with exception of estriol and prednisolone which showed recoveries of 66 and 82%, respectively. [ABSTRACT FROM AUTHOR]