Pastor Belda, Marta

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Pastor Belda, Marta

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Pastor Belda, Marta

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Universidad de Murcia. Departamento de Química Analítica

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Open Access
Fingerprinting of volatile organic compounds and discrimination of pear samples by gas chromatography-ion mobility spectrometry
(Elsevier, 2025-05-20) Giménez Campillo, Claudia; Pastor Belda, Marta; Campillo Seva, Natalia; Arroyo Manzanares, Natalia; Viñas López-Pelegrin, Pilar; Química Analítica
The pear contains many volatile organic compounds that are responsible for its distinctive aroma, flavour and texture. The aim of this work was to develop, optimise and validate an analytical method for the determination of volatile compounds in pears using headspace gas chromatography coupled to ion mobility spectrometry. A total of 254 samples from four cultivars were analysed, and a partial least squares discriminant analysis model using 93 markers allowed differentiation between cultivars with 100 % accuracy and a Q2 of 0.878. Additionally, a total of 227 Ercoline pears collected at different stages of ripening were analysed. For the first time, a predictive model based on 75 markers was used to determine pear ripeness, achieving 100 % accuracy and a Q2 of 0.856. A total of 22 compounds were identified and quantified in the samples and key compounds were determined for each cultivar and ripening stage.
Open Access
Ultrasound assisted extraction approach to test the effect of elastic rubber nettings on the N-nitrosamines content of ham meat samples
(MDPI, 2021-10-24) Giménez Campillo, Claudia; Pastor Belda, Marta; Campillo Seva, Natalia; Hernández, Juan de Dios; Guillén, Isidro; Vizcaíno, Pascuala; López García, Ignacio Francisco; Hernández Córdoba, Manuel; Arroyo Manzanares, Natalia; Viñas López-Pelegrin, Pilar; Química Analítica
Nitrosamines (NAs), which are catalogued as carcinogenic compounds, may be present in meat products due to the conversion of nitrites and as result of migration from elastic rubber nettings used. A method based on ultrasonic assisted extraction coupled with dispersive liquid–liquid microextraction as sample treatment and gas chromatography-mass spectrometry as separation and detection technique was proposed for the determination of twelve NAs in cooked ham samples. The method was validated by evaluating linearity (0.5–1000 ng g−1), matrix effect, sensitivity (detection limits were between 0.15 and 1.4 ng g−1) and precision, which was below 12%. Five NAs were found in the samples with levels ranging from not quantifiable to 40 ng g−1. The effect of the elastic rubber nettings on the nitrosamine content of meat was evaluated by comparing the levels found in products made with several plastics or thread in the presence of additives.
Open Access
El estándar perfecto. Calibración externa
(2026-02-27) Giménez Campillo, Claudia; García Nicolás, María; Castell Martínez, Ana; Arroyo Manzanares, Natalia; Pastor Belda, Marta; Química Analítica; Facultades de la UMU::Facultad de Química
Relaciona la señal instrumental de una muestra desconocida con la de patrones de concentración conocida para cuantificar el analito.
Open Access
Fingerprinting of peach during the ripening process using an analytical platform with spectrometric and volatilome-based chromatographic techniques
(American Chemical Society , 2025-06-23) Giménez Campillo, Claudia; Arroyo Manzanares, Natalia; Pastor Belda, Marta; Campillo Seva, Natalia; Lukas Bodenbender; Weller, Philipp; Viñas López-Pelegrin, Pilar; Química Analítica
In recent years, the quality of peaches has been related to their early harvest, so this work has focused on the characterization of the spectral fingerprint using Fourier transform near-infrared spectroscopy, and headspace gas chromatography (HS-GC) coupled to ion mobility spectrometry (IMS) and mass spectrometry (MS) based on their volatilome or volatile organic compound content, with the aim of identifying the optimum ripening point of peaches. A total of 344 samples of two different varieties at all ripening stages were analyzed. The principal component analysis (PCA) showed a clear tendency for samples at the same stage of ripening to form visible clusters. The groups identified by PCA were used to construct partial least-squares discriminant analysis models that allowed differentiation according to ripening and variety. The overall results were very promising, especially for the volatilomes measured by HS-GC−IMS and HS-GC−MS.
Open Access
Targeted and untargeted approaches using liquid chromatography with high-resolution mass spectrometry for the determination of lipophilic marine biotoxins in seawater and mussel samples
(Elsevier, 2025-09-12) Pastor Belda, Marta; Arroyo Manzanares, Natalia; Viñas López-Pelegrin, Pilar; Sánchez Fernández, Olga; Pérez Ruzafa, Ángel; Campillo Seva, Natalia; León Morán, Lixy Olinda; Química Analítica
Marine biotoxins are naturally occurring compounds produced around the world by various species of microalgae, whose presence increases significantly due to harmful algal blooms. This phenomenon is a major public health concern, as a large amount of marine fauna is exposed to these biotoxins. The aim of this study was the improvement and application of dispersive liquid-liquid microextraction and liquid chromatography coupled to high-resolution mass spectrometry for the determination of eight lipophilic marine biotoxins, okadaic acid (OA), dinophysistoxin 1 (DTX-1), dinophysistoxin 2 (DTX-2), 16:0 7-O-acyl okadaic acid (DTX-3a), gambierone (GAM), 44-methylgambierone (44-GAM), yessotoxin (YTX), and homoyessotoxin (hYTX), and their derivatives in seawaters and mussels by targeted and untargeted approaches. The proposed method provided detection limits ranging from 0.0004 to 1.7 ng mL-1 in seawater and 0.06 to 119 ng g-1 in mussel samples, depending on the biotoxin. A total of 23 seawater samples collected in the Mar Menor lagoon between 2021 and 2023 were analyzed and several of them were found to contain OA and DTX-3a at concentration levels in the 0.006–1.5 ng mL-1 range. OA and DTX-2 were also found at maximum levels of 8.0 and 1.2 ng g-1, respectively, in several mussel samples from commercial origin. In addition, a suspect screening was developed in the untargeted approach to investigate the presence of other derivatives of the target marine biotoxins in the samples using a home-made database covering 93 compounds. An unsaturated ester derivative of OA/DTX-2 was detected in the seawater samples collected during a red tide.
Open Access
Monitorization of ibuprofen, diclofenac and triclosan and their photolytic transformation products
(Elsevier, 2025-06-03) León Morán, Lixy Olinda; Pastor Belda, Marta; Campillo Seva, Natalia; Arroyo Manzanares, Natalia; Viñas López-Pelegrin, Pilar; Martínez-Escudero, Carmen Maria; Garrido, Isabel; Contreras, Fulgencio; Hellín, Pilar; Flores, Pilar; Aliste, Marina; Fenoll, José; Química Analítica; Facultades de la UMU::Facultad de Química
The presence of contaminants of emerging concern (CECs) in wastewater treatment plant (WWTP) effluents poses a significant risk to human health and the environment. The application of photolytic processes in remediation of WWTP effluents results in the formation of transformation products (TPs) with unknown environmental impact. Thus, the identification of TPs and the monitoring of their evolution during the remediation process is of great interest. This study presents a new analytical method for the determination of three CECs (ibuprofen, IBU; diclofenac, DCF; triclosan, TCS) and their respective TPs in water subjected to direct photolysis by ultraviolet A irradiation with light emitting diode lamps. The analytes were extracted using in situ ionic liquid dispersive liquid–liquid microextraction and analysed by liquid chromatography with high resolution mass spectrometry (LC-HRMS) for the identification of known and unknown TPs. The identification of TPs was conducted through two untargeted strategies: a suspect screening based on the utilization of a home-made database created from the TPs previously described, and a screening for novel TPs based on the spectral investigation of a deconvoluted and aligned list of peaks with suitable degradation trends. The proposed analytical strategy allowed up to 39 TPs being identified, with 10 of them being structurally proposed for the first time in this study. In addition, verification of the identified TPs was carried out by LC with triple quadrupole. Moreover, the three CECs and their TPs were monitored in four WWTP samples subjected to degradation trials and two TPs (DCF-TP296C and TCS-TP303C) were found.
Open Access
Dilute-and-shoot-liquid chromatography-quadrupole time of flight-mass spectrometry for pteridine profiling in human urine and its association with different pathologies
(MDPI, 2023-06-01) Giménez Campillo, Claudia; Pastor Belda, Marta; Arroyo Manzanares, Natalia; Campillo Seva, Natalia; Val Oliver, Blanca del; Zarauz García, José; Sáenz, Luis; Viñas López-Pelegrin, Pilar; Química Analítica
Pteridines are a group of compounds synthesised by many living organisms that are involved in the metabolism of many cofactors and vitamins. Their concentration in biological fluids may be altered by various pathologies such as cancer or inflammatory bowel disease, urine being the main route of excretion. In this study, three lumazines and ten pterins were analysed in their native oxidation state using high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. Their high concentration in urine samples and their good ionisation behaviour allow the use of the dilute-and-shoot method by simple filtration of the urine prior to chromatographic analysis. The final method offers excellent linearity, sensitivity and precision parameters, and a total of 135 urine samples were analysed from patients with some relevant information such as faecal calprotectin (FCP) levels, common diseases such as diabetes, hypertension and dyslipidaemia and immunological diseases such as inflammatory bowel disease (IBD). The pteridine profile was related to FCP levels without showing any correlation. In addition, pteridine levels were compared between healthy subjects and IBD, diabetic, hypertensive and dyslipidaemic patients, and significant differences were found between the two groups for some of the pteridines.
Open Access
Discrimination of the geographical origin of peaches by the monitoring of volatile organic compounds by gas chromatography with mass spectrometry and chemometric tools
(Elsevier, 2024-02-24) Giménez Campillo, Claudia; Arroyo Manzanares, Natalia; Pastor Belda, Marta; Campillo Seva, Natalia; Viñas López-Pelegrin, Pilar; Química Analítica
The peach is one of the most popular and widely consumed fruits in Europe. Spain is the largest peach-producing country in the world with several growing areas recognised by consumers. This work focuses on the development, optimisation and validation of a non-targeted metabolomics strategy for the determination of peach volatile organic compounds from different origins by headspace gas chromatography coupled to mass spectrometry (HS–GC–MS). The volatil profile found in each sample is used to classify peaches according to their origin. The results obtained were processed using MS-DIAL software and 279 features were detected, of which 102 volatile compounds were tentatively identified and 30 of them could also be quantified. In addition, the areas of all the features were used to build models based on orthogonal partial least squares discriminant analysis (OPLS-DA) to differentiate peaches according to their geographical origin. A very promising model was obtained, with a validation rate of 90.32%, which means that it could be used to guarantee the Protected Designation of Origin of different peaches with a simple analysis.
Restricted
Degradation of imidacloprid in water by photo-Fenton process using UV-LED lamps at neutral pH: Study of intermediate products by liquid chromatography mass spectrometry after dispersive liquid–liquid microextraction
(Elsevier, 2024-03-01) Martínez Escudero, Carmen Maria; Garrido, Isabel; Contreras, Fulgencio; Hellín, Pilar; Flores, Pilar; Arroyo Manzanares, Natalia; Campillo Seva, Natalia; Pastor Belda, Marta; Viñas López-Pelegrin, Pilar; Fenoll, José; León Morán, Lixy Olinda; Química Analítica
In the present study, a suitable analytical method to determine imidacloprid (IMI) and its main transformation products (TPs) in water by means of dispersive liquid–liquid microextraction (DLLME) combined with liquid chromatography coupled to mass spectrometry (LC-MS), using both quadrupole-time-of-flight (QTOF) and triple quadrupole (QqQ) analysers, has been developed. In addition, the structures of major products formed when IMI is photo-oxidized using ultraviolet A (UVA) irradiation with light emitting diode (LED) lamps were established. Finally, the behaviour of IMI and its main TPs generated in water during photo-Fenton processes at neutral pH using two ferric iron complexes, with ethylenediamine-N,N-disuccinic acid (EDDS) and nitrilotriacetic acid (NTA) as chelating agents, was studied. DLLME was found to efficiently preconcentrate IMI and IMI TPs from the water matrix using chloroform (as extractant solvent) and acetonitrile (as dispersant solvent) in a simple step. The selectivity of the used techniques provided unequivocal identification of IMI and its TPs and their quantification with high sensitivity during the photo-Fenton treatments. In addition, the photo-Fenton treatment using EDDS exhibited higher degradation rate than photo-Fenton treatment using NTA.
Open Access
Controlando la variabilidad analítica. Estándar interno
(2026-02-27) Giménez Campillo, Claudia; García Nicolás, María; Castell Martínez, Ana; Arroyo Manzanares, Natalia; Pastor Belda, Marta; Química Analítica; Facultades de la UMU::Facultad de Química
Técnica de corrección en tiempo real que compensa errores aleatorios y sistemáticos mediante la medida simultánea de un estándar interno (EI) o de referencia añadido a todas las muestras y estándares analíticos.