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1.
Analyst ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042100

RESUMEN

Ambient Ionization Mass Spectrometry (AI-MS) techniques have revolutionized analytical chemistry by enabling rapid analysis of samples under atmospheric conditions with minimal to no preparation. In this study, the optimization of a cold atmospheric plasma for the analysis of food and pharmaceutical samples, liquid and solid, using a Heat-Assisted Dielectric Barrier Discharge Ionization (HA-DBDI) source is described. A significant enhancement in analyte signals was observed when a heating element was introduced into the design, potentially allowing for greater sensitivity. Furthermore, the synergy between the inlet temperature of the mass spectrometer and the heating element allows for precise control over the analytical process, leading to improved detection sensitivity and selectivity. Incorporating computational fluid dynamic (CFD) simulations into the study elucidated how heating modifications can influence gas transport properties, thereby facilitating enhanced analyte detection and increased signal intensity. These findings advance the understanding of HA-DBDI technology and provide valuable insights for optimizing AI-MS methodologies for a wide range of applications in food and pharmaceutical analysis.

2.
Mol Cell Biochem ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970706

RESUMEN

Alzheimer's disease (AD) progression is closely linked to the propagation of pathological Amyloid ß (Aß), a process increasingly understood to involve extracellular vesicles (EVs), namely exosomes. The specifics of Aß packaging into exosomes remain elusive, although evidence suggests an ESCRT (Endosomal Sorting Complex Required for Transport)-independent origin to be responsible in spreading of AD pathogenesis. Intriguingly, PrPC, known to influence exosome abundance and bind oligomeric Aß (oAß), can be released in exosomes via both ESCRT-dependent and ESCRT-independent pathways, raising questions about its role in oAß trafficking. Thus, we quantified Aß levels within EVs, cell medium, and intracellularly, alongside exosome biogenesis-related proteins, following deletion or overexpression of PrPC. The same parameters were also evaluated in the presence of specific exosome inhibitors, namely Manumycin A and GW4869. Our results revealed that deletion of PrPC increases intracellular Aß accumulation and amplifies EV abundance, alongside significant changes in cellular levels of exosome biogenesis-related proteins Vps25, Chmp2a, and Rab31. In contrast, cellular expression of PrPC did not alter exosomal Aß levels. This highlights PrPC's influence on exosome biogenesis, albeit not in direct Aß packaging. Additionally, our data confirm the ESCRT-independent exosome release of Aß and we show a direct reduction in Chmp2a levels upon oAß challenge. Furthermore, inhibition of opposite exosome biogenesis pathway resulted in opposite cellular PrPC levels. In conclusion, our findings highlight the intricate relationship between PrPC, exosome biogenesis, and Aß release. Specifically, they underscore PrPC's critical role in modulating exosome-associated proteins, EV abundance, and cellular Aß levels, thereby reinforcing its involvement in AD pathogenesis.

3.
Chemosphere ; 357: 142075, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38648985

RESUMEN

Pesticides are considered one of the main sources of contamination of surface waters, especially in rural areas highly influenced by traditional agricultural practices. The objective of this work was to evaluate the impact caused by pesticides and their transformation products (TPs) related to olive groves in surface waters with strong agricultural pressure. 11 streams were monitored during four sampling campaigns over 2 years. A solid-phase extraction, followed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) analysis was used in the quantitative target approach, with more than 70 validated compounds. Target method was combined with a suspect screening strategy involving more than 500 pesticides and TPs, using ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) to identify additional pesticides and TPs out of the scope of analysis. A total of 43 different compounds were detected with the target method. The herbicide MCPA was present in all samples and at the highest concentration (1260 ng L-1), followed by the fungicide carbendazim (1110 ng L-1), and the herbicide chlorotoluron (706 ng L-1). The suspect screening strategy revealed the presence of 7 compounds out of the target analysis (1 pesticide and 6 TPs). 6 analytes were confirmed with the analytical standards. Semi-quantification results revealed that TPs exhibited higher concentrations than their corresponding parent compounds, indicating higher persistency. Some small streams showed a comparable number of pesticides and concentrations to the most polluted large river. The determined pesticide and TPs concentrations represented an estimated environmental hazard in almost all sampling sites under study. This work underscores the importance of including pesticide TPs and small streams impacted by extensive agricultural activities in water quality monitoring programs.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Olea , Plaguicidas , Ríos , Espectrometría de Masas en Tándem , Contaminantes Químicos del Agua , Ríos/química , Contaminantes Químicos del Agua/análisis , Plaguicidas/análisis , Medición de Riesgo , Olea/química , Extracción en Fase Sólida , Carbamatos/análisis , Cromatografía Líquida de Alta Presión , Herbicidas/análisis , Bencimidazoles/análisis , Compuestos de Fenilurea
4.
Talanta ; 274: 126011, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38574537

RESUMEN

In this article, we have studied the potential of flexible microtube plasma (FµTP) as ionization source for the liquid chromatography high-resolution mass spectrometry detection of non-easily ionizable pesticides (viz. nonpolar and non-ionizable by acid/basic moieties). Phthalimide-related compounds such as dicofol, dinocap, o-phenylphenol, captan, captafol, folpet and their metabolites were studied. Dielectric barrier discharge ionization (DBDI) was examined using two electrode configurations, including the miniaturized one based on a single high-voltage (HV) electrode and a virtual ground electrode configuration (FµTP), and also the two-ring electrode DBDI configuration. Different ionization pathways were observed to ionize these challenging, non-easily ionizable nonpolar compounds, involving nucleophilic substitutions and proton abstraction, with subtle differences in the spectra obtained compared with APCI. An average sensitivity increase of 5-fold was attained compared with the standard APCI source. In addition, more tolerance with matrix effects was observed in both DBDI sources. The importance of the data reported is not just limited to the sensitivity enhancement compared to APCI, but, more notably, to the ability to effectively ionize nonpolar, late-eluting (in reverse-phase chromatography) non-ionizable compounds. Besides o-phenylphenol ([M - H]-), all the parent species were efficiently ionized through different mechanisms involving bond cleavages through the effect of plasma reagent species or its combination with thermal degradation and subsequent ionization. This tool can be used to figure out overlooked nonpolar compounds in different environmental samples of societal interest through non-target screening (NTS) strategies.


Asunto(s)
Espectrometría de Masas , Plaguicidas , Plaguicidas/análisis , Plaguicidas/química , Plaguicidas/sangre , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Ftalimidas/química , Ftalimidas/análisis , Contaminación de Alimentos/análisis , Miniaturización , Captano/análisis , Captano/sangre , Captano/química , Análisis de los Alimentos/métodos
5.
Anal Chem ; 96(13): 5289-5297, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38507224

RESUMEN

Paper spray mass spectrometry (PS-MS) has evolved into a promising tool for monitoring reactions in thin films and microdroplets, known as reactive PS, alongside its established role in ambient and direct ionization. This study addresses the need for rapid, cost-effective methods to improve analyte identification in biofluids by leveraging reactive PS-MS in clinical chemistry environments. The technique has proven effective in derivatizing target analytes, altering hydrophobicity to enhance elution and ionization efficiency, and refining detection through thin-film reactions on paper, significantly expediting reaction rates by using amino acids (AAs) as model analytes. These molecules are prone to interacting with substrates like paper, impeding elution and detection. Additionally, highly abundant species in biofluids, such as lipids, often suppress AA ionization. This study employs the Schiff base (SB) reaction utilizing aromatic aldehydes for AA derivatization to optimize reaction conditions time, temperature, and catalyst presence and dramatically increasing the conversion ratio (CR) of formed SB. For instance, using leucine as a model AA, the CR surged from 57% at room temperature to 89% at 70 °C, with added pyridine during and after 7.5 min, displaying a 43% CR compared to the bulk reaction. Evaluation of various aromatic aldehydes as derivatization agents highlighted the importance of specific oxygen substituents for achieving higher conversion rates. Furthermore, diverse derivatization agents unveiled unique fragmentation pathways, aiding in-depth annotation of the target analyte. Successfully applied to quantify AAs in human and rat plasma, this reactive PS-MS approach showcases promising potential in efficiently detecting conventionally challenging compounds in PS-MS analysis.


Asunto(s)
Aminoácidos , Bases de Schiff , Humanos , Animales , Ratas , Espectrometría de Masas/métodos , Aminas , Aldehídos/análisis
6.
Anal Chem ; 95(50): 18370-18378, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-37902451

RESUMEN

The present study investigated the potential for solvent-assisted laser desorption coupled with flexible microtube plasma ionization mass spectrometry (SALD-FµTP-MS) as a rapid analytical technique for direct analysis of surface-deposited samples. Paper was used as the demonstrative substrate, and an infrared hand-held laser was employed for sample desorption, aiming to explore cost-effective sampling and analysis methods. SALD-FµTP-MS offers several advantages, particularly for biofluid analysis, including affordability, the ability to analyze low sample volumes (<10 µL), expanded chemical coverage, sample and substrate stability, and in situ analysis and high throughput potential. The optimization process involved exploring the use of viscous solvents with high boiling points as liquid matrices. This approach aimed to enhance desorption and ionization efficiencies. Ethylene glycol (EG) was identified as a suitable solvent, which not only improved sensitivity but also ensured substrate stability during analysis. Furthermore, the addition of cosolvents such as acetonitrile/water (1:1) and ethyl acetate further enhanced sensitivity and reproducibility for a standard solution containing amphetamine, imazalil, and cholesterol. Optimized conditions for reproducible and sensitive analysis were determined as 1000 ms of laser exposure time using a 1 µL solvent mixture of 60% EG and 40% acetonitrile (ACN)/water (1:1). A mixture of 60% EG and 40% ACN/water (1:1) resulted in signal enhancements and relative standard deviations of 12, 20, and 13% for the evaluated standards, respectively. The applicability of SALD-FµTP-MS was further evaluated by successfully analyzing food, water, and biological samples, highlighting the potential of SALD-FµTP-MS analysis, particularly for thermolabile and polarity diverse compounds.


Asunto(s)
Rayos Láser , Agua , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Solventes , Reproducibilidad de los Resultados , Acetonitrilos
7.
J Am Soc Mass Spectrom ; 34(6): 1145-1152, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37231669

RESUMEN

Dielectric barrier discharges (DBD) are highly versatile plasma sources for forming ions at atmospheric pressure and near ambient temperatures for the rapid, direct, and sensitive analysis of molecules by mass spectrometry (MS). Ambient ion sources should ideally form intact ions, as in-source fragmentation can limit sensitivity, increase spectral complexity, and hinder interpretation. Here, we report the measurement of ion internal energy distributions for the four primary classes of DBD-based ion sources, specifically DBD ionization (DBDI), low-temperature plasma (LTP), flexible microtube plasma (FµTP), and active capillary plasma ionization (ACaPI), in addition to atmospheric pressure chemical ionization (APCI) using para-substituted benzylammonium thermometer ions. Surprisingly, the average extent of energy deposited by the use of ACaPI (90.6 kJ mol-1) was ∼40 kJ mol-1 lower than the other ion sources (DBDI, LTP, FµTP, and APCI; 130.2 to 134.1 kJ mol-1) in their conventional configurations, and slightly higher than electrospray ionization (80.8 kJ mol-1). The internal energy distributions did not depend strongly on the sample introduction conditions (i.e., the use of different solvents and sample vaporization temperatures) or the DBD plasma conditions (i.e., maximum applied voltage). By positioning the DBDI, LTP, and FµTP plasma jets on axis with the capillary entrance to the mass spectrometer, the extent of internal energy deposition could be reduced by up to 20 kJ mol-1, although at the expense of sensitivity. Overall, the use of an active capillary-based DBD can result in substantially less fragmentation of ions with labile bonds than alternate DBD sources and APCI with comparably high sensitivity.

8.
Mass Spectrom Rev ; 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37010157

RESUMEN

In food analysis, conventional one-dimensional liquid chromatography methods sometimes lack sufficient separation power due to the complexity and heterogeneity of the analysed matrices. Therefore, the use of two-dimensional liquid chromatography (2D-LC) turns out to be a powerful tool to consider, especially when coupled to mass spectrometry (MS). This review presents the most remarkable 2D-LC-MS food applications reported in the last 10 years, including a critical discussion of the multiple approaches, modulation strategies as well as the importance of the optimisation of the different analytical aspects that will condition the 2D-LC-MS performance. The presence of contaminants in food (food safety), the food quality and authenticity or the relationship between the beneficial effects of food and human health are some of the fields in which most of the 2D-LC-MS applications are mainly focused. Both heart-cutting and comprehensive applications are described and discussed in this review, highlighting the potential of 2D-LC-MS for the analysis of such complex samples.

9.
Mass Spectrom Rev ; 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37056215

RESUMEN

In food analysis, conventional one-dimensional liquid chromatography methods sometimes lack sufficient separation power due to the complexity and heterogeneity of the analyzed matrices. Therefore, the use of two-dimensional liquid chromatography (2D-LC) turns out to be a powerful tool to consider, especially when coupled to mass spectrometry (MS). This review presents the most remarkable 2D-LC-MS food applications reported in the last 10 years, including a critical discussion of the multiple approaches, modulation strategies as well as the importance of the optimization of the different analytical aspects that will condition the 2D-LC-MS performance. The presence of contaminants in food (food safety), the food quality, and authenticity or the relationship between the beneficial effects of food and human health are some of the fields in which most of the 2D-LC-MS applications are mainly focused. Both heart-cutting and comprehensive applications are described and discussed in this review, highlighting the potential of 2D-LC-MS for the analysis of such complex samples.

10.
Anal Chem ; 95(2): 854-861, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36538370

RESUMEN

Dielectric barrier discharge ionization (DBDI) is a versatile tool for small-molecule mass spectrometry applications, helping cover from polar to low polar molecules. However, the plasma gas-phase interactions are highly complex and have been scarcely investigated. The ionization mechanisms of plasmas have long been assumed to be somewhat similar to atmospheric pressure chemical ionization (APCI). Here, we evaluated the ionization mechanisms of a two-ring DBDI ion source, using different discharge gases to analyze vaporized liquid samples. Polycyclic aromatic hydrocarbons (PAHs) were used as model analytes to assess the mechanisms' dominance: protonation, [M + H]+, or radical ion species formation, [M]·+. In the present work, two different ionization trends were observed for APCI and DBDI during the PAH analysis; the compounds with proton affinities (PA) over 856 kJ/mol were detected as [M + H]+ when APCI was used as ionization source. Meanwhile, independently of the PA, DBDI showed the prevalence of charge exchange reactions. The addition of dopants in the gas-phase region shifted the ionization mechanisms toward charge exchange reactions, facilitating the formation of [M]·+ ion species, showing anisole a significant boost of the PAH radical ion species signals, over nine times for Ar-Prop-DBDI analysis. The presence of high-energy metastable atoms (e.g., HeM) with high ionization potentials (IE = 19.80 eV) did not show boosted PAH abundances or extensive molecule fragmentation. Moreover, other species in the plasma jet region with closer and more appropriate IE, such as N2 B3Πg excited molecules, are likely responsible for PAH Penning ionization.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Humanos , Hidrocarburos Policíclicos Aromáticos/análisis , Espectrometría de Masas/métodos
11.
J Sep Sci ; 45(16): 3105-3114, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35801641

RESUMEN

Dielectric barrier discharge ionization has gained attention in the last few years due to its versatility and the vast array of molecules that can be ionized. In this study, we report on the assessment of liquid chromatography coupled to dielectric barrier discharge ionization with mass spectrometry for neutral lipid analysis. A set of different neutral lipid subclasses (triacylglycerides, diacylglycerides, and sterols) were selected for the study. The main species detected from our ionization source were [M-H2 O+H]+ , [M+H]+ or [M-R-H2 O+H]+ , attributed to sterol dehydration, protonation or the fragmentation of an acyl chain accompanied by a water loss of the glycerolipids, respectively. In terms of sensitivity, the dielectric barrier discharge displayed overall improved abundances and comparable or better limits of quantitation than atmospheric pressure chemical ionization for both acylglycerols and sterols. As a case study, different archaeological samples with variable content in neutral lipids, particularly triacylglycerides, were studied. The identification was carried out by combining accurate mass and the tentative formula associated with the exact mass, retention time matching with standards, and additional structural information from in-source fragmentation. The high degree of unsaturation and the presence of sterols revealed the potential vegetal origin of the material stored in the analyzed samples.


Asunto(s)
Presión Atmosférica , Esteroles , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Espectrometría de Masas , Espectrometría de Masa por Ionización de Electrospray
12.
Front Neurol ; 13: 826102, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309552

RESUMEN

The accumulation of proteinaceous deposits comprised largely of the α-synuclein protein is one of the main hallmarks of Parkinson's disease (PD) and related synucleinopathies. Their progressive development coincides with site-specific phosphorylation, oxidative stress and eventually, compromised neuronal function. However, modeling protein aggregate formation in animal or in vitro models has proven notably difficult. Here, we took advantage of a preclinical organotypic brain slice culture model to study α-synuclein aggregate formation ex vivo. We monitored the progressive and gradual changes induced by α-synuclein such as cellular toxicity, autophagy activation, mitochondrial dysfunction, cellular death as well as α-synuclein modification including site-specific phosphorylation. Our results demonstrate that organotypic brain slice cultures can be cultured for long periods of time and when cultured in the presence of aggregated α-synuclein, the molecular features of PD are recapitulated. Taken together, this ex vivo model allows for detailed modeling of the molecular features of PD, thus enabling studies on the cumulative effects of α-synuclein in a complex environment. This provides a platform to screen potential disease-modifying therapeutic candidates aimed at impeding α-synuclein aggregation and/or cellular transmission. Moreover, this model provides a robust replacement for in vivo studies that do not include behavioral experiments, thus providing a way to reduce the number of animals used in an accelerated timescale.

13.
Proc Natl Acad Sci U S A ; 119(12): e2111405119, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35294277

RESUMEN

SignificanceOur results demonstrate the existence of early cellular pathways and network alterations in oligodendrocytes in the alpha-synucleinopathies Parkinson's disease and multiple system atrophy. They further reveal the involvement of an immune component triggered by alpha-synuclein protein, as well as a connection between (epi)genetic changes and immune reactivity in multiple system atrophy. The knowledge generated in this study could be used to devise novel therapeutic approaches to treat synucleinopathies.


Asunto(s)
Células Madre Pluripotentes Inducidas , Atrofia de Múltiples Sistemas , Enfermedad de Parkinson , Sinucleinopatías , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Atrofia de Múltiples Sistemas/metabolismo , Oligodendroglía/metabolismo , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
14.
Anal Chim Acta ; 1179: 338835, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34535252

RESUMEN

Although electron impact ionization (EI) remains the standard ionization source for GC-MS, it presents extensive fragmentation as its main limitation. The potential of a novel plasma-based soft ionization source named controlled-atmosphere flexible microtube plasma (CA-FµTP) has been evaluated in this work for the determination of monoaromatic volatile BTEX group (namely benzene, toluene, ethylbenzene, and o-, m- and p-xylenes) in olive oil, based on headspace technique. The obtained results show an attractive advantage over EI due to no fragmentation was observed. A nitrosated ion [M + NO]+ is obtained as the most abundant species. Thus, the BTEX mass spectrum identification can be carried out without major effort. In general, the sensitivity for CA-FµTP was comparable to those obtained by EI, achieving LODs ranged from 0.6 to 1.0 µg kg-1. The potential usefulness of GC-CA-FµTP-MS for the detection of BTEX was demonstrated by analyzing olive oil samples and identifying traces of these compounds in one sample. Therefore, the proposed plasma-based soft ionization is suitable for BTEX analysis in fatty complex matrixes as olive oil.


Asunto(s)
Derivados del Benceno , Xilenos , Atmósfera , Benceno/análisis , Derivados del Benceno/análisis , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Aceite de Oliva , Tolueno/análisis , Xilenos/análisis
15.
Food Chem ; 365: 130486, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34237571

RESUMEN

After more than ten years since pesticide residues were detected in citrus-flavored soft drinks, this study reveals that the situation has not changed. A new sensitive multiresidue UHPLC-MS/MS method has been validated for 88 pesticides, which was used to analyze 200 samples manufactured in 67 countries, 80% corresponding to fruit-based soft drinks. The results show that 98% of the samples collected worldwide contained at least one pesticide, and 85% of them contained more than 4 pesticides. 40 out of 88 target compounds were quantified among the screened samples. Europe was the world region with the highest total amount of pesticides, probably due to the higher content of juice concentrate in samples, which may be the main source of the pesticide residues. Nevertheless, residues were also found in samples with no juice, so water quality also plays an important role as the main ingredient of citrus-flavored soft drinks.


Asunto(s)
Citrus , Residuos de Plaguicidas , Bebidas Gaseosas/análisis , Contaminación de Alimentos/análisis , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem
16.
Acta Neuropathol Commun ; 9(1): 46, 2021 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-33743820

RESUMEN

Alpha-synuclein (α-syn) aggregation is the hallmark pathological lesion in brains of patients with Parkinson's disease (PD) and related neurological disorders characterized as synucleinopathies. Accumulating evidence now indicates that α-syn deposition is also present within the gut and other peripheral organs outside the central nervous system (CNS). In the current study, we demonstrate for the first time that α-syn pathology also accumulates within the liver, the main organ responsible for substance clearance and detoxification. We further demonstrate that cultured human hepatocytes readily internalize oligomeric α-syn assemblies mediated, at least in part, by the gap junction protein connexin-32 (Cx32). Moreover, we identified a time-dependent accumulation of α-syn within the liver of three different transgenic (tg) mouse models expressing human α-syn under CNS-specific promoters, despite the lack of α-syn mRNA expression within the liver. Such a brain-to-liver transmission route could be further corroborated by detection of α-syn pathology within the liver of wild type mice one month after a single striatal α-syn injection. In contrast to the synucleinopathy models, aged mice modeling AD rarely show any amyloid-beta (Aß) deposition within the liver. In human post-mortem liver tissue, we identified cases with neuropathologically confirmed α-syn pathology containing α-syn within hepatocellular structures to a higher degree (75%) than control subjects without α-syn accumulation in the brain (57%). Our results reveal that α-syn accumulates within the liver and may be derived from the brain or other peripheral sources. Collectively, our findings indicate that the liver may play a role in the clearance and detoxification of pathological proteins in PD and related synucleinopathies.


Asunto(s)
Encéfalo/metabolismo , Encéfalo/patología , Hígado/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , alfa-Sinucleína/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Enfermedad por Cuerpos de Lewy/metabolismo , Enfermedad por Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/fisiopatología , Masculino , Ratones , Ratones Transgénicos , Microscopía Electrónica de Transmisión , Enfermedad de Parkinson/fisiopatología , Sinucleinopatías/metabolismo , Sinucleinopatías/patología , Sinucleinopatías/fisiopatología
17.
Food Chem ; 347: 129020, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33482490

RESUMEN

Datura species are well known because of their high concentration of tropane alkaloids, which has led to poisoning episodes when Datura is accidentally mixed with edible crops. Therefore, the European Union has set a maximum level in cereal-based infant food products of 1 µg kg-1 for atropine and scopolamine. However, the occurrence of these compounds in other commodities has become a global concern. Spinach and derived products can be contaminated with Datura innoxia leaves. In this study, we tested frozen spinachs and spinach-based infant food products. The determination was carried out by UHPLC-MS/MS after applying the QuEChERS method as sample treatment. The LOQs were below 0.016 µg kg-1, achieving satisfactory results in terms of precision, accuracy, and matrix effects. The obtained results (ranging between 0.02 and 8.19 µg kg-1) were close to the maximum level set by the European Union for 24% of the samples tested.


Asunto(s)
Atropina/análisis , Cromatografía Líquida de Alta Presión/métodos , Datura/química , Análisis de los Alimentos , Escopolamina/análisis , Espectrometría de Masas en Tándem/métodos , Spinacia oleracea
18.
Anal Methods ; 12(40): 4831-4852, 2020 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-33000770

RESUMEN

Ambient mass spectrometry refers to the family of techniques that allows ions to be generated from condensed phase samples under ambient conditions and then, collected and analysed by mass spectrometry. One of their key advantages relies on their ability to allow the analysis of samples with minimal to no sample workup. This feature maps well to the requirements of food safety testing, in particular, those related to the fast determination of pesticide residues in foods. This review discusses the application of different ambient ionization methods for the qualitative and (semi)quantitative determination of pesticides in foods, with the focus on different specific methods used and their ionization mechanisms. More popular techniques used are those commercially available including desorption electrospray ionization (DESI-MS), direct analysis on real time (DART-MS), paper spray (PS-MS) and low-temperature plasma (LTP-MS). Several applications described with ambient MS have reported limits of quantitation approaching those of reference methods, typically based on LC-MS and generic sample extraction procedures. Some of them have been combined with portable mass spectrometers thus allowing "in situ" analysis. In addition, these techniques have the ability to map surfaces (ambient MS imaging) to unravel the distribution of agrochemicals on crops.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Agroquímicos/análisis , Frutas/química , Espectrometría de Masas , Residuos de Plaguicidas/análisis
19.
Sci Total Environ ; 715: 137005, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32041002

RESUMEN

The presence of pesticide residues in bees is of great interest, given the central role of bees as indicators for environmental assessment. The goal of this article is to propose a method to capture enhanced chemical information for these central environmental indicators. Most of the methods rely on the analysis of pooled samples rather than individual specimens due to practical sample preparation method considerations and limitations in sensitivity. This leads to miss information on the mapping of pesticides and actual amount of pesticide per specimen. In this article, a nanoflow liquid chromatography system coupled to high resolution mass spectrometry (using a hybrid quadrupole-Orbitrap instrument) has been applied for the development of a multiresidue pesticide method for the determination of 162 multiclass pesticides in specific part of honeybee samples (ca. abdomen, head or thorax). The reduced flow rate provided an enhancement in sensitivity and a strong reduction of matrix effects, thus only a quick and simple ultrasound assisted extraction using minute amount of sample was required. Satisfactory results were obtained for all tested analytes with concentration levels detected lower than 0.5 ng g-1 in all cases, thus being acceptable for monitoring purposes. Matrix effect was negligible for 94% of compounds. Extraction recoveries ranged from 70% to 105%, being within SANTE guidelines. Finally, the applicability of the method was demonstrated, by successful application to the analysis of contaminated honeybee samples, extracting useful information from specific bee parts of single specimens, thus, enabling pseudo spatially resolved chemical information.


Asunto(s)
Residuos de Plaguicidas/análisis , Animales , Abejas , Cromatografía Liquida , Espectrometría de Masas en Tándem
20.
Sci Total Environ ; 697: 134058, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31487597

RESUMEN

Emerging contaminants (ECs) such as pharmaceuticals, personal care products, drugs of abuse and polar pesticides are under particular attention due to their high consumption, frequent detection in the environment and reported ecotoxicological risk. This study investigates the occurrence and distribution of multiclass of ECs in surface waters at basin scale of two Atlantic coastal lagoons of Uruguay, South America. For this purpose, a target screening approach covering up to 362 compounds was employed using nanoflow liquid chromatography - high resolution mass spectrometry (nanoLC/HRMS). 56 compounds were identified including five banned pesticides in the European Union: atrazine, carbendazim, chlorpyrifos ethyl, diazinon, and ethion. Pharmaceuticals, hormones and drugs of abuse showed maximum detection frequencies and concentrations downstream cities. The highest occurrence of pesticides was found in lagoons and streams with neighboring agricultural activity. ECs were also found in coastal sea. Environmental risk assessment revealed that the hormones 17α-ethinylestradiol and 17-ß-estradiol showed the highest risk to aquatic organisms in these basins. This study represents the first basin- scale monitoring of ECs in superficial waters encompassing streams, lagoons, and coastal seas in Uruguay, South America.

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