28 research outputs found

    Environmental chiral analysis of beta-blockers: evaluation of different n-alkyl-modified SBA-15 mesoporous silicas as sorbents in solid-phase extraction

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    The extraction and preconcentration of chiral beta-blockers in environmental water was evaluated by solidphase extraction (SPE) employing an SBA-15 ordered mesoporous silica functionalised with alkyl chains of different length. The materials were characterised by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, nitrogen adsorption-desorption isotherm measurements and elemental analysis. Important parameters influencing extraction efficiency, including the type and amount of sorbent and the breakthrough volume, were optimised. The results obtained showed that the organic chain length played an important role in the behaviour of these sorbents. Under optimised conditions, using 200 mg SBA-15-C8 as sorbent, a simple analytical method based on off-line SPE coupled to chiral capillary electrophoresis with diode array detection (SPE-chiral CE-DAD) was developed. Method detection and quantification limits were lower than 0.6 and 1.9 mu g L-1 respectively for all enantiomers, with a preconcentration factor of 500-fold. The method was successfully applied to the chiral analysis of atenolol, metoprolol, pindolol and propranolol in river and sewage water samples. Satisfactory recoveries (between 86 +/- 2 and 98 +/- 1 %) and repeatability (relative standard deviation (RSD) < 9 %, n = 3) were obtained. Metoprolol was detected in sewage water at a concentration of 10.7 and 9.9 mu g L-1 and an enantiomeric fraction of 0.52 and 0.48 for the first- and the second-migrating enantiomers respectively. These results emphasise the importance of enantioselective analysis for environmental risk assessment

    One-pot synthesized functionalized mesoporous silica as a reversed-phase sorbent for solid-phase extraction of endocrine disrupting compounds in milks

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    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 1.36 μg/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

    Ordered mesoporous silica functionalized with beta-cyclodextrin derivative for stereoisomer separation of flavanones and flavanone glycosides by nano-liquid chromatography and capillary electrochromatography

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    In this paper a chiral stationary phase (CSP) was prepared by the immobilization of a beta-CD derivative (3,5-dimethylphenylcarbamoylated beta-CD) onto the surface of amino-functionalized spherical ordered mesoporous silica (denoted as SM) via a urea linkage using the Staudinger reaction. The CSP was packed into fused silica capillaries 100 mu m I.D. and evaluated by means of nano-liquid chromatography (nano-LC) and capillary electrochromatography (CEC) using model compounds for the enantio- and the diastereomeric separation. The compounds flavanone, 2'-hydroxyflavanone, 4'-hydroxyflavanone, 6hydroxyflavanone, 4'-methoxyflavanone, 7-methoxyfiavanone, hesperetin, hesperidin, naringenin, and naringin were studied using reversed and polar organic elution modes. Baseline stereoisomer resolution and good results in terms of peak efficiency and short analysis time of all studied flavonoids and flavanones glycosides were achieved in reversed phase mode, using as mobile phase a mixture of MeOH/H2O, 10 mM ammonium acetate pH 4.5 at different ratios. For the polar organic mode using 100% of MeOH as mobile phase, the CSP showed better performances and the baseline chiral separation of several studied compounds occurred in an analysis time of less than 10 min. Good results were also achieved by CEC employing two different mobile phases. The use of MeOH/H2O, 5 mM ammonium acetate buffer pH 6.0 (90/10, v/v) was very effective for the chiral resolution of flavanone and its methoxy and hydroxy derivatives. (C) 2017 Elsevier B.V. All rights reserved

    Development of a digital mission diary based on overcoming different challenges to improve the academic performance of students in the degree of Food Science and Technology

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    [EN] This work describes the implementation of a teaching innovation activity based on gamification within the degree in Food Science and Technology at the Rey Juan Carlos University during the 2022-2023 academic year. The activity was carried out voluntarily in the subject of Analysis and Control of Food Quality in the 3rd year to get an extra score in the final grade. The main objective was to encourage the study, motivation and autonomous work of the students. Accordingly, the activity involved the development of a digital mission diary by each student based on overcoming a set of challenges related to the solid phase extraction technique used in food analysis field. These challenges were part of a training itinerary with different levels that the students had to overcome week by week. The results obtained show an improvement in the academic performance of the participating students, who, by carrying out the activity, have also developed general and specific skills useful to improve their understanding of other degree subjects and to address their Final Degree Project.[ES] Este trabajo describe la implantación de una actividad de innovación docente basada en la metodología activa de la gamificación dentro del grado en Ciencia y Tecnología de los Alimentos de la Universidad Rey Juan Carlos durante el curso académico 2022-2023. La actividad se realizó en la asignatura de Análisis y Control de la Calidad de los Alimentos de 3º curso de forma voluntaria para conseguir una puntuación extra en la calificación final. El principal objetivo fue incentivar el estudio, la motivación y el trabajo autónomo de los estudiantes. Para ello, la actividad consistió en la creación de un diario de misión digital por parte de cada estudiante basado en la superación de un conjunto de retos relacionados con la técnica de extracción en fase sólida en el análisis de alimentos. Estos retos formaban parte de un itinerario formativo con distintos niveles que debían ir superando semana a semana. Los resultados obtenidos demuestran una mejora del rendimiento académico de los estudiantes participantes, los cuales al realizar la actividad también han desarrollado competencias generales y específicas útiles para mejorar la compresión de otras asignaturas del grado y para abordar su Trabajo Fin de Grado.Escuela Superior de Ciencias Experimentales y Tecnología de la Universidad Rey Juan Carlos a través de la Ayuda concedida en la Convocatoria para la distribución de presupuestos de 2023 destinados a Actividades de Innovación Docente en la ESCETCasado, N.; Gañán, J.; González Gómez, L.; Casado Hidalgo, G.; Morante Zarcero, S.; Sierra, I. (2023). Creación de un diario de misión digital basado en la superación de distintos retos para mejorar el rendimiento académico de los estudiantes del grado en Ciencia y Tecnología de los Alimentos. Editorial Universitat Politècnica de València. 626-640. https://doi.org/10.4995/INRED2023.2023.1656062664

    Application of the QuEChERS Strategy as a Useful Sample Preparation Tool for the Multiresidue Determination of Pyrrolizidine Alkaloids in Food and Feed Samples: A Critical Overview

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    The identification of concerning high levels of pyrrolizidine alkaloids (PAs) in a wide variety of food products has raised the occurrence of these natural toxins as one of the main current issues of the food safety field. Consequently, a regulation with maximum concentration levels of these alkaloids has recently been published to monitor their occurrence in several foodstuffs. According to legislation, the analytical methodologies developed for their determination must include multiresidue extractions with high selectivity and sensitivity, as a set of 21 + 14 PAs should be simultaneously monitored. However, the multiresidue extraction of these alkaloids is a difficult task due to the high complexity of food and feed samples. Accordingly, although solid-phase extraction is still the technique most widely used for sample preparation, the QuEChERS method can be a suitable alternative for the simultaneous determination of multiple analytes, providing green extraction and clean-up of samples in a quick and cost-effective way. Hence, this review proposes an overview about the QuEChERS concept and its evolution through different modifications that have broadened its applicability over time, focusing mainly on its application regarding the determination of PAs in food and feed, including the revision of published works within the last 11 years

    Application of the QuEChERS Strategy as a Useful Sample Preparation Tool for the Multiresidue Determination of Pyrrolizidine Alkaloids in Food and Feed Samples: A Critical Overview

    No full text
    The identification of concerning high levels of pyrrolizidine alkaloids (PAs) in a wide variety of food products has raised the occurrence of these natural toxins as one of the main current issues of the food safety field. Consequently, a regulation with maximum concentration levels of these alkaloids has recently been published to monitor their occurrence in several foodstuffs. According to legislation, the analytical methodologies developed for their determination must include multiresidue extractions with high selectivity and sensitivity, as a set of 21 + 14 PAs should be simultaneously monitored. However, the multiresidue extraction of these alkaloids is a difficult task due to the high complexity of food and feed samples. Accordingly, although solid-phase extraction is still the technique most widely used for sample preparation, the QuEChERS method can be a suitable alternative for the simultaneous determination of multiple analytes, providing green extraction and clean-up of samples in a quick and cost-effective way. Hence, this review proposes an overview about the QuEChERS concept and its evolution through different modifications that have broadened its applicability over time, focusing mainly on its application regarding the determination of PAs in food and feed, including the revision of published works within the last 11 years

    Evaluation of Thermal Degradation of Tropane and Opium Alkaloids in Gluten-Free Corn Breadsticks Samples Contaminated with Stramonium Seeds and Baked with Poppy Seeds under Different Conditions

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    In this work, the thermal degradation of tropane and opium alkaloids was studied in samples of breadsticks prepared with corn flour, contaminated with seeds of Datura stramonium, and containing seeds of Papaver somniferum L. A total of seven different samples were prepared and eight alkaloids were studied, three tropane (atropine, scopolamine, and anisodamine) and five opium (morphine, codeine, thebaine, papaverine, and noscapine) alkaloids. For this purpose, a fast, easy and efficient method based on solid-liquid extraction (SLE) prior to the analysis by high-performance liquid chromatography with a diode array detector (HPLC-DAD) was developed and validated. Thermal degradation studies showed a decrease in the TAs and OAs content under baking (180 &deg;C for 20 min) that was between 7&ndash;65% for atropine, depending on the preparation conditions used, between 35&ndash;49% for scopolamine and anisodamine, up to 100% for morphine and codeine and between 14&ndash;58% for thebaine, papaverine, and noscapine. Results also evidenced that degradation of morphine and codeine was higher when the seeds were added as topping to the breadsticks

    Study of the Phenolic Compound Profile of <i>Arbutus unedo</i> L. Fruits at Different Ripening Stages by HPLC-TQ-MS/MS

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    Arbutus unedo L. berries have traditionally been used as edible and medicinal fruits in folk medicine for the treatment of some pathologies. Besides their good nutritional properties, these berries are rich in bioactive compounds. Accordingly, a HPLC-triple quadrupole (TQ)-MS/MS method was developed and validated for the first time to characterize the changes produced in the phenolic composition profile of A. unedo L. fruits through three ripening stages. Several hydroxycinnamic and hydroxybenzoic acids were detected, gallic acid being the highest phenolic acid quantified. Quercetin, quercetin-3-β-glucoside, rutin, and kaempferol were found in similar amounts at the different maturity stages. High amounts of (+)-catechin, procyanidin B2, epigallocatechin, and (−)-epigallocatechin gallate were observed in the unripe fruits. Naringin and vitexin were also quantified. Stilbenes, such as trans-resveratrol and trans-piceid, were identified for the first time in these fruits. Total phenolic compounds, total anthocyanin compounds, and radical scavenging activity were also determined in the fruits harvested at different years in several locations of the Iberian Peninsula at different ripening stages. The results confirmed that these fruits are an excellent source of these bioactive compounds (mainly flavanols) with high antioxidant activity, which could be used as a new source for preparation of nutraceutical or functional foods

    Development of a Green, Quick, and Efficient Method Based on Ultrasound-Assisted Extraction Followed by HPLC-DAD for the Analysis of Bioactive Glycoalkaloids in Potato Peel Waste

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    α-Solanine and α-chaconine are the two most predominant glycoalkaloids (GAs) present in potato. Potato peel contains a high concentration of GAs, which are especially interesting for application in the pharmaceutical industry due to their different beneficial properties (such as anticarcinogenic, anti-inflammatory, antiallergic, antipyretic, antiviral, fungicide, and antibiotic activities, among others); so, potato peel waste can be valorized by extracting these biologically active compounds. For this, a green, quick, and efficient miniaturized analytical approach based on ultrasound-assisted extraction (UAE) combined with HPLC-DAD was developed to quantify α-solanine and α-chaconine in potato peel. Some parameters of the extraction were optimized, including the extraction method, the type of solvent, and the sample/solvent ratio, by a three-factor, three-level (33) full factorial experimental design. The optimal extraction conditions were obtained with UAE using methanol as a solvent and a sample/solvent ratio of 1:10 (w/v, g/mL). The analytical greenness metric for sample preparation (AGREEprep) tool was used to assess the greenness of the methods used. The tool revealed an acceptable green analysis, with 0.61 points. The method was validated and applied to the evaluation of GAs in the peel of 15 commercial varieties of potato. The amount of glycoalkaloids found in the samples evaluated ranged from 143 to 1273 mg/kg and from 117 to 1742 mg/kg dry weight for α-solanine and α-chaconine, respectively. These results reveal the important variability that exists between potato varieties; so, their analysis is of great importance to select the most suitable ones for biovalorization (e.g., the Amandine and Rudolph varieties, with around 3000 mg/kg, in total, of both GAs). To provide higher stability to the peel during storage, freeze-drying or a medium-temperature drying process resulted preferable to avoid GA degradation. Overall, this study will contribute to the expansion of the future biovalorization of potato peel waste as well as provide a powerful analytical tool for GA analysis
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