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1.
J Chromatogr A ; 1707: 464303, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37607428

RESUMEN

The herein presented work aims to the development of an easy method for the quantitative determination of parabens and bisphenols in human salivabased on the use of methyl chloroformate as a derivatizing agent, followed by solid-phase microextraction (SPME) and gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS) analysis with selected reaction monitoring (SRM). Using multivariate analysis, two derivatization strategies were compared and optimized, demonstrating that the use of methyl chloroformate led to better sensitivity than the classical derivatization by acetic anhydride. Good performance in the sorption process of the derivatized target analytes was obtained using the most recent commercialized overcoated fiber (PDMS/DVB/PDMS). The validation procedure of the final protocol led to satisfactory results in terms of linearity, limit of quantitation, accuracy, and precision. All parabens were quantified from 10 ng/L using the developed method, except for methylparaben, which was quantified from 100 ng/L along with all bisphenols. Intra- and inter-day accuracy and intra- and inter-day precision can be considered satisfactory for all analytes (values between 73% and 118%), except for the inter-day accuracy of BPF. Quite good results also in terms of matrix effect were obtained for the target compounds (range 71% to 118%, RSD% less than 13.6%), except for BPA at the middle concentration and MeP at the lowest concentration. The greenness of the method was evaluated and the results indicated that our approach is more eco-friendly than previously published methods. Based on its characteristics, the presented method can be considered a suitable approach to determine parabens and bisphenols in routine analysis for biomonitoring purposes.


Asunto(s)
Parabenos , Microextracción en Fase Sólida , Humanos , Cromatografía de Gases y Espectrometría de Masas , Saliva , Espectrometría de Masas en Tándem
2.
Toxics ; 11(6)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37368599

RESUMEN

The increasing use of agrochemicals, including fertilizers and herbicides, has led to worrying metal contamination of soils and waters and raises serious questions about the effects of their transfer to different levels of the trophic web. Accumulation and biomagnification of essential (K, Na, Mg, Zn, Ca), nonessential (Sr, Hg, Rb, Ba, Se, Cd, Cr, Pb, As), and rare earth elements (REEs) were investigated in newly emerged adults of Tenebrio molitor exposed to field-admitted concentrations of a metribuzin-based herbicide and an NPK blend fertilizer. Chemical analyses were performed using inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) supported by unsupervised pattern recognition techniques. Physiological parameters such as cuticle melanization, cellular (circulating hemocytes), and humoral (phenoloxidase enzyme activity) immune responses and mass loss were tested as exposure markers in both sexes. The results showed that NPK fertilizer application is the main cause of REE accumulation in beetles over time, besides toxic elements (Sr, Hg, Cr, Rb, Ba, Ni, Al, V, U) also present in the herbicide-treated beetles. The biomagnification of Cu and Zn suggested a high potential for food web transfer in agroecosystems. Gender differences in element concentrations suggested that males and females differ in element uptake and excretion. Differences in phenotypic traits show that exposure affects metabolic pathways involving sequestration and detoxification during the transition phase from immature-to-mature beetles, triggering a redistribution of resources between sexual maturation and immune responses. Our findings highlight the importance of setting limits for metals and REEs in herbicides and fertilizers to avoid adverse effects on species that provide ecosystem services and contribute to soil health in agroecosystems.

3.
Talanta ; 258: 124410, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36878086

RESUMEN

This work proposes a new method for the quantification of benzothiazoles (BTs), benzotriazoles (BTRs), and benzenesulfonamides (BSAs) in tap water, river water, and wastewater. The protocol involved the use of microextraction by packed sorbent (MEPS), applied for the first time for the extraction of the target analytes, combined with programmed temperature vaporization-gas chromatography-triple quadrupole mass spectrometry (PTV-GC-QqQ-MS). Considering the synergism between MEPS extraction and PTV injection, the experimental variables affecting their performance were simultaneously optimized by "experimental design", while principal component analysis (PCA) was used to find the overall optimal working conditions. Response surface methodology was used to gain a comprehensive understanding of the effects of working variables on method performance. The developed method achieved very good linearities and satisfactory intra- and inter-day accuracies and precisions. The protocol permitted the detection of the target molecules with limit of detection (LODs) values between 0.005 and 0.85 µg/L. The green character of the procedure was evaluated using three metrics: "Analytical Eco-Scale", "Green Analytical Procedure Index" (GAPI), and "Analytical Greenness metric for sample preparation (AGREEprep). The satisfactory results obtained with real water samples demonstrate the applicability of the method for monitoring campaigns and exposome studies.

4.
Int J Mol Sci ; 23(16)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36012426

RESUMEN

Lead (Pb), due to its high toxicity and bioaccumulation tendency, is one of the top three pollutants of concern for both humans and wildlife and occupies second place in the Priority List of Hazardous Substances. In freshwater fish, Pb is mainly absorbed through the gills, where the greatest accumulation occurs. Despite the crucial role of gills in several physiological functions such as gas exchange, water balance, and osmoregulation, no studies evaluated the effects of environmentally relevant concentrations of Pb on this organ, and existing literature only refers to high levels of exposure. Herein we investigated for the first time the molecular and morphological effects induced by two low and environmentally relevant concentrations of Pb (2.5 and 5 µg/L) on the gills of Danio rerio, a model species with a high translational value for human toxicity. It was demonstrated that Pb administration at even low doses induces osmoregulatory dysfunctions by affecting Na+/K+-ATPase and AQP3 expression. It was also shown that Pb upregulates MTs as a protective response to prevent cell damage. Modulation of SOD confirms that the production of reactive oxygen species is an important toxicity mechanism of Pb. Histological and morphometric analysis revealed conspicuous pathological changes, both dose- and time-dependent.


Asunto(s)
Branquias , Contaminantes Químicos del Agua , Animales , Agua Dulce , Branquias/metabolismo , Humanos , Plomo/farmacología , Contaminantes Químicos del Agua/metabolismo , Pez Cebra/metabolismo
5.
Chemosphere ; 307(Pt 4): 136095, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35995187

RESUMEN

Heavy metal contamination is recognized worldwide as a serious threat to human health and wildlife, and reducing their emissions is a priority of international and EU actions. Due to its persistence, high bioaccumulation tendency, and toxicity properties, lead (Pb) is one of the heavy metals of greatest concern. Even at low concentrations, lead induces various clinical and subclinical conditions in both humans and animals, and it has been included in the priority list of hazardous substances. In the present study, we used zebrafish's early stages as a model, given their well-acknowledged predictive value in the risk assessment of chemicals. This study was designed to investigate the morphological and morphometric alterations induced by Pb during zebrafish's early development and disclose the putative effects stage- and/or dose-dependent. We examined injuries induced by two environmentally relevant and extremely low concentrations of Pb (2.5 µg/L and 5 µg/L) during two exposure windows: early (between 1 and 7 dpf) and late (between 2 and 8 dpf). We clearly demonstrated that the incidence and severity of morphological abnormalities increased with increasing Pb dose and exposure time in both early and late-exposed groups. Furthermore, we revealed that malformation severity was significantly higher in the early exposed group than in the late exposure group at all exposure times and for both tested doses, thus highlighting the high sensitivity of zebrafish during the initial stages of development. The information presented in this paper emphasizes the effectiveness of morphological biomarkers in unveiling threatening situations and supports the role of zebrafish embryos and larvae in risk assessment and environmental monitoring.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Animales , Biomarcadores , Sustancias Peligrosas , Humanos , Larva , Plomo/toxicidad , Contaminantes Químicos del Agua/toxicidad , Pez Cebra
6.
Molecules ; 27(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35889523

RESUMEN

Pendimethalin-based herbicides are used worldwide for pre-emergence selective control of annual grasses and weeds in croplands. The endurance of herbicides residues in the environment has an impact on the soil biodiversity and fertility, also affecting non-target species, including terrestrial invertebrates. Carabid beetles are known as natural pest control agents in the soil food web of agroecosystems, and feed on invertebrates and weed seeds. Here, a mass spectrometry untargeted profiling of haemolymph is used to investigate Pterostichus melas metabolic response after to pendimethalin-based herbicide exposure. Mass spectrometric data are examined with statistical approaches, such as principal component analysis, for possible correlation with biological effects. Those signals with high correlation are submitted to tandem mass spectrometry to identify the associated biomarker. The time course exposure showed many interesting findings, including a significant downregulation of related to immune and defense peptides (M-lycotoxin-Ls4a, Peptide hormone 1, Paralytic peptide 2, and Serine protease inhibitor 2). Overall, the observed peptide deregulations concur with the general mechanism of uptake and elimination of toxicants reported for Arthropods.


Asunto(s)
Escarabajos , Herbicidas , Compuestos de Anilina/química , Animales , Herbicidas/análisis , Herbicidas/toxicidad , Espectrometría de Masas , Péptidos , Suelo/química
7.
Environ Pollut ; 285: 117487, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34090069

RESUMEN

Benzothiazoles (BTHs), benzotriazoles (BTRs), and benzenesulfonamides (BSAs) are chemicals used in several industrial and household applications. Despite these compounds are emerging pollutants, there is still a lack of information about their presence in outdoor air samples. In this paper, we developed a new method for the quantification of BTHs, BTRs, and BSAs in airborne particulate matter (PM10). The extraction of fourteen analytes from PM10 was accomplished by microwave-assisted extraction (MAE) using an environmentally friendly mixture of water and ethanol. SPME was used to analyze the target compounds from the MAE extract by gas chromatography-tandem mass spectrometry (SPME-GC-MS/MS), eliminating additional sample clean-up steps. The best working conditions for MAE and SPME were examined multivariately by experimental design techniques. The target compounds were quantified in selected reaction monitoring acquisition mode. The proposed method was carefully validated, and the achieved results were satisfactory in terms of linearity, lower limit of quantification (picograms per cubic meter), intra- and inter-day accuracy (81-118% and 82-114%, respectively), and precision (repeatability and reproducibility in the range 2.3-17% and 7.4-19%, respectively). The application in a real monitoring campaign showed that the developed protocol is a valuable and eco-friendly alternative to the methods proposed so far.


Asunto(s)
Microextracción en Fase Sólida , Contaminantes Químicos del Agua , Benzotiazoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Microondas , Reproducibilidad de los Resultados , Proyectos de Investigación , Espectrometría de Masas en Tándem , Triazoles , Contaminantes Químicos del Agua/análisis
8.
Sci Total Environ ; 749: 141438, 2020 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-32827832

RESUMEN

The continuous and extensive application of agrochemicals leads to the accumulation of heavy metals (HMs) and rare earth elements (REEs) in agricultural soils and their transfer in the food web with consequent relevant risks for human and ecosystem health. In this study, HM and REE concentrations were quantified in the soil of wheat crop fields conventionally managed in the agricultural areas of Sila Mountain (Southern Italy) and compared with the concentration in a field of wild herbs, used as control. Statistical analyses and principal component analysis suggested that the use of pesticides, herbicides and fertilizers contributes to the accumulation of HMs and REEs in the soil. Different accumulation patterns were recorded in treated fields as a consequence of the type and amount of agrochemical used and the crop rotation. The exposure risk associated with the transfer through the tropic levels of agroecosystem was carried out measuring the concentration of HMs and REEs in adults of Harpalus (Pseudoophonus) rufipes (De Geer, 1774) collected from each monitored site. Different accumulation patterns found in specimens from the monitored sites highlighted the ability of this generalist predator to regulate metal uptake under field conditions. The values of bioaccumulation factor (BAF) allow to defining the order of accumulation in P. rufipes which was classified as a macroconcentrator of Cd, Cu, Mg and Zn. Our results can supplement the limited information regarding the REE accumulation in soil invertebrates and may provide reference data for assessing potential environmental risks in croplands.


Asunto(s)
Escarabajos , Metales Pesados , Metales de Tierras Raras , Contaminantes del Suelo , Adulto , Agroquímicos , Animales , Bioacumulación , China , Ecosistema , Monitoreo del Ambiente , Humanos , Italia , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
9.
J Sep Sci ; 43(15): 3061-3073, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32399997

RESUMEN

In the following work, a new method for the analysis of the phthalate monoesters in human urine was reported. Phthalate monoesters are metabolites generated as a result of phthalate exposure. In compliance with the dictates of Green Analytical Chemistry, a rapid and simple protocol was developed and optimized for the quantification of phthalate monoesters (i.e., monoethyl phthalate, monoisobutyl phthalate, mono-n-butyl phthalate, mono-(2-ethylhexyl) phthalate, mono-n-octyl phthalate, monocyclohexyl phthalate, mono-isononyl phthalate) in human urine, which entails preceding derivatization with methyl chloroformate combined with the use of commercial solid phase microextraction and the analysis by gas chromatography-triple quadrupole mass spectrometry. The affinity of the derivatized analytes toward five commercial coatings was evaluated, and in terms of analyte extraction, the best results were reached with the use of the divinylbenzene/carboxen/polydimethylsiloxane fiber. The multivariate approach of experimental design was used to seek for the best working conditions of the derivatization reaction and the solid phase microextraction, thus obtaining the optimum response values. The proposed method was validated according to the guidelines issued by the Food and Drug Administration achieving satisfactory values in terms of linearity, sensitivity, matrix effect, intra- and inter-day accuracy, and precision.


Asunto(s)
Cromatografía de Gases/métodos , Ésteres/orina , Ácidos Ftálicos/orina , Microextracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Membranes (Basel) ; 10(5)2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32397308

RESUMEN

The aim of this work was to analyze the potential of reverse osmosis (RO) membranes in the recovery and concentration of aroma compounds from orange juice evaporator condensate (EC) streams. Concentration experiments were performed by using three RO spiral-wound aromatic polyamide membranes (SG1812C-34D, SC1812C-34D and SE1812) with different NaCl rejections. The effect of transmembrane pressure, axial feed flowrate and volume concentration ratio (VCR) on permeate flux was studied. Rejections of the investigated membranes towards specific aroma compounds (octanol, α-terpineol, terpinen-4-ol, cis-carveol, karvon, linalool) in selected operating conditions were also evaluated. The concentrations of the aroma compounds were determined by gas chromatography coupled with mass spectrometry (GC-MS) using headspace solid-phase microextraction (HS-SPME) as a sample preparation approach. For all selected membranes, the permeate flux increased linearly by increasing the operating pressure from 5 to 25 bar; on the other hand, the feed flowrate did not have any significant effect on the permeate flux. High retention values towards aroma compounds (>80%) were measured for all selected membranes. However, the SC membrane showed the highest rejection values (>96%) and the best correlation between concentration factor of aroma compounds and VCR.

11.
Neurol Sci ; 40(9): 1939-1942, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31054066

RESUMEN

The present pilot study was undertaken to investigate the impaired acquired color vision on Calabrian male sample showing this parameter as a biological marker in type 2 diabetes. All patients and controls underwent three pseudo-isochromatic clinical test batteries: Ishihara test, Farnsworth test, and City University test. The results show a specific loss of short-wavelength (blue sensitivity) and typical tritan responses in diabetic patients. Generally, in later stages of the disease, the red-green mechanisms are involved. By the impaired color vision study in diabetic patients, we can confirm the impaired retina-brain cortex pathway. We believe that the above not invasive test analysis can support the other instrumental and imaging analysis to study the impaired retina-brain cortex pathway. Moreover, we think that the present clinical method can be useful in terms of preventive medicine.


Asunto(s)
Corteza Cerebral/fisiopatología , Percepción de Color/fisiología , Defectos de la Visión Cromática/fisiopatología , Complicaciones de la Diabetes/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Retina/fisiopatología , Vías Visuales/fisiopatología , Anciano , Anciano de 80 o más Años , Pruebas de Percepción de Colores , Defectos de la Visión Cromática/etiología , Diabetes Mellitus Tipo 2/complicaciones , Humanos , Italia , Masculino , Persona de Mediana Edad , Proyectos Piloto
12.
Int Ophthalmol ; 39(3): 671-676, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29392642

RESUMEN

OBJECTIVE: To assess the type and degree of both red-green and blue-yellow color vision deficiencies of Calabrian males affected by multiple sclerosis. MATERIAL: Eighty Calabrian male patients were enrolled (age range 18-70 years; mean age 40.6 ± 12.4 years) showing a disease duration mean of 10.6 ± 8.2 years (range = 0.5-46 years) coming from the Institute of Neurology, Magna Graecia University, Catanzaro. Optic neuritis present in the medical histories of the 21 patients does not influence color vision. Excluding seven colorblind subjects and one affected by a bilateral maculopathy, the analyzed sample group was 72. Seventy controls were matched for age and sex. METHOD: An ophthalmologist examined all patients and controls in order to rule out diabetic retinopathy, cataracts, senile maculopathy, or ocular fundus' anomalies. The Ishihara test identified the colorblind patients. The City University Test screened for people with abnormal color vision by grading the severity of color vision deficiency. The second part of the City University Test as well as the Farnsworth Test confirmed both the color vision deficiency type and degree. RESULTS: Fifty-one percentage (37/72) of the patients showing a color vision deficiency were subdivided into two subgroups: subgroup one showed red-green deficiency (57%, 21/37); subgroup two showed a coupled red-green and blue-yellow deficiency (43%, 16/37). Furthermore, we found two distinct curves showing a groove within the first 10 years of the disease. Both monocular and binocular analyses allowed us to identify the patients showing the monocular color vision deficiency, but they were well compensated by binocular vision. CONCLUSION: We think that the majority of the patients with the red-green deficiency will develop the coupled red-green and blue-yellow deficiency in the latter years of multiple sclerosis.


Asunto(s)
Pruebas de Percepción de Colores/métodos , Percepción de Color/fisiología , Defectos de la Visión Cromática/diagnóstico , Visión de Colores/fisiología , Diagnóstico Precoz , Esclerosis Múltiple/complicaciones , Adolescente , Adulto , Anciano , Defectos de la Visión Cromática/etiología , Defectos de la Visión Cromática/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Agudeza Visual , Adulto Joven
13.
Materials (Basel) ; 11(11)2018 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-30453695

RESUMEN

The aim of this project was to study the treatment of industrial waste using ETS-10 zeolite. The pollutants that must be removed were metals sourced from zinc ferrite, a processing waste derived from the use of mineral-containing zinc. The first phase of the work involved the characterization of the industrial waste, zinc ferrite, in order to deepen the knowledge regarding its nature and composition. The second phase involved the removal of the metals released by the zinc ferrite in aqueous systems using the ETS-10 phase as an ion exchanger. Different chemical and physical techniques were used: plasma mass spectrometry, X-ray diffraction, scanning electron microscopy, microanalysis, and thermal analyses. A comparison between ETS-10 and commercial zeolite A performance, in the same aqueous systems, was carried out. The results showed that the metal removal efficiency of ETS-10 phase is higher than that obtained by commercial zeolite A, especially towards dangerous heavy metals such as Pb, Zn and Mn.

14.
Inorg Chem ; 57(21): 13895-13900, 2018 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-30351058

RESUMEN

We report two new highly crystalline metal-organic frameworks (MOFs), derived from the natural amino acids serine (1) and threonine (2), featuring hexagonal channels densely decorated with hydroxyl groups belonging to the amino acid residues. Both 1 and 2 are capable of discriminating, via solid-phase extraction, a mixture of selected chloride salts of lanthanides on the basis of their size, chemical affinity, and/or the flexibility of the network. In addition, this discrimination follows a completely different trend for 1 and 2 because of the different locations of the hydroxyl groups in each compound, which is evocative of steric complementarity between the substrate and receptor. Last but not least, the crystal structures of selected adsorbates could be resolved, offering unprecedented snapshots on the capture process and enabling structural correlations with the separation mechanism.

15.
Talanta ; 189: 657-665, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30086975

RESUMEN

Particulate matter (PM) is among the most dangerous air pollutants, and there is a growing concern related to the effects of airborne particles on human health. Their harmful effects can be derived are directly linked to the size of particles themselves and the associated pollutants after they have been taken up by inhalation. In this work was developed a new analytical method for the quantification of organophosphorus esters (OPE) bound to airborne PM. The proposed protocol provides for the microwave-assisted extraction (MAE) of the analytes from the PM followed by solid-phase microextraction gas chromatography-tandem mass spectrometry determination (SPME-GC-MS/MS). Unlike to the traditional protocol, which provides for the use of tedious Soxhlet extraction with environmentally damaging organic solvents, the proposed method allows for a reliable quantification by using an eco-friendly hydroalcoholic mixture (water/ethanol; 50:50, v/v). The method was developed using as target compounds ten organophosphate esters, namely tripropyl phosphate (TPP), tri-n-butyl phosphate (TBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP), tris(1,3-dichloro-2-propyl) phosphate (TDCPP), tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), 2-ethylhexyl-diphenyl phosphate (EHDPP), tris(2-ethylhexyl) phosphate (TEHP) and tricresyl phosphate (TCP). The extraction performance of five SPME fibers was evaluated and the DVB/CAR/PDMS coating demonstrated to be the most suitable for the extraction of the target analytes. Experimental Design was used for the multivariate optimization of the parameters affecting the MAE process as well as the SPME extraction, and the optimal working conditions were determined by using Derringer's desirability function. The developed method was validated in terms of linearity, sensitivity (LLOQ values of 0.5 ng/mL for TDCPP and 0.1 ng/mL for the other analytes), matrix effect (81-117%), intra and inter day accuracy (83-115% and 80-115%, respectively), and precision (repeatability and reproducibility in the range 1.0-12.4% and 2.3-15.2%, respectively). The satisfactory performances reached make the proposed protocol a green and high-throughput alternative for OPE quantification in particulate matter.

16.
Neurol Sci ; 39(7): 1283-1287, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29651719

RESUMEN

European people believed that epilepsy was both a sacred and demoniac disease in the pre- and post-Hippocratic Age, and this belief continued into the Christian era. Epilepsy was wrapped in mystery. The present work shows an epileptic treatment using elk (Alces alces) hoof, which was better known among Northern European people, and explains its historical and popular origins that lead to its importance and success within the Official Medicine in the sixteenth and seventeenth centuries until its gradual decline as a specific treatment in the subsequent centuries. We study authors from both Antiquity and the Modern Age. The present work concludes by highlighting the relationship between epilepsy and its magic-religious inheritance. It could be considered a valid example showing how a popular treatment can earn honors in the Official Pharmacopoeia, but later be excluded.


Asunto(s)
Ciervos , Epilepsia/historia , Pezuñas y Garras , Medicina Tradicional/historia , Animales , Epilepsia/terapia , Equidae , Europa (Continente) , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia Antigua , Historia Medieval , Religión y Medicina
17.
J Chromatogr A ; 1549: 1-13, 2018 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-29573783

RESUMEN

Polyamines are aliphatic amines with low molecular weight that are widely recognized as one of the most important cancer biomarkers for early diagnosis and treatment. The goal of the work herein presented is the development of a rapid and simple method for the quantification of free polyamines (i.e., putrescine, cadaverine, spermidine, spermine) and N-monoacetylated polyamines (i.e., N1-Acetylspermidine, N8-Acetylspermidine, and N1-Acetylspermine) in human urine. A preliminary derivatization with propyl chloroformate combined with the use of solid phase microextraction (SPME) allowed for an easy and automatable protocol involving minimal sample handling and no consumption of organic solvents. The affinity of the analytes toward five commercial SPME coatings was evaluated in univariate mode, and the best result in terms of analyte extraction was achieved using the divinylbenzene/carboxen/polydimethylsiloxane fiber. The variables affecting the performance of SPME analysis were optimized by the multivariate approach of experimental design and, in particular, using a central composite design (CCD). The optimal working conditions in terms of response values are the following: extraction temperature 40 °C, extraction time of 15 min and no addition of NaCl. Analyses were carried out by gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS) in selected reaction monitoring (SRM) acquisition mode. The developed method was validated according to the guidelines issued by the Food and Drug Administration (FDA). The satisfactory performances reached in terms of linearity, sensitivity (LOQs between 0.01 and 0.1 µg/mL), matrix effect (68-121%), accuracy, and precision (inter-day values between -24% and +16% and in the range 3.3-28.4%, respectively) make the proposed protocol suitable to be adopted for quantification of these important biomarkers in urine samples.


Asunto(s)
Bioensayo , Formiatos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Poliaminas/orina , Microextracción en Fase Sólida/métodos , Adulto , Femenino , Humanos , Límite de Detección , Masculino , Reproducibilidad de los Resultados , Cloruro de Sodio , Solventes , Espectrometría de Masas en Tándem , Temperatura
18.
J Sep Sci ; 41(4): 929-939, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29193803

RESUMEN

In this work, a polydimethylsiloxane/divinylbenzene fiber overcoated with a layer of polydimethylsiloxane was evaluated as analytical sampling tool for the first time in human urine. Urinary polycyclic aromatic hydrocarbons with 2-6 aromatic rings were considered as target compounds. The analyte uptake in kinetic and thermodynamic regime was evaluated and compared to the performances of polydimethylsiloxane/divinylbenzene and polydimethylsiloxane fibers. The assessment of the robustness and endurance of the overcoated fiber was carried out by direct immersion solid-phase microextraction in undiluted urine performing up to 120 consecutive extractions. The overcoated fiber was then used to develop a fast and easy direct immersion solid-phase microextraction with gas chromatography and triple quadrupole mass spectrometry protocol for the quantification of the target polycyclic aromatic hydrocarbons. The attained values of accuracy and precision were 75-114% and 2-19%, respectively, while the limits of quantification ranged between 0.05 and 1 ng/L. The proposed protocol was applied to the screening of urine samples collected from smoking and nonsmoking volunteers. The successful results obtained by using the overcoated fiber create not only new alternatives for polycyclic aromatic hydrocarbon exposure assessment but also new perspectives for the application of direct immersion solid-phase microextraction to the analysis of bioclinical matrixes.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/orina , Microextracción en Fase Sólida , Adulto , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Adulto Joven
20.
Anal Bioanal Chem ; 409(30): 7105-7120, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29032454

RESUMEN

In this work, organophosphate ester flame retardant (OPFRs) assay in environmental waters was addressed by using microextraction by packed sorbent (MEPS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). Ten OPFRs with different physicochemical properties were taken into account as target compounds for a comprehensive method evaluation. Five MEPS cartridges (i.e., C2, C8, C18, Silica, and DVB) and seven solvents (i.e., methanol, ethyl acetate, methyl tert-butyl ether, hexane, acetonitrile, dichloromethane, and trichloromethane) were surveyed. The analysis was performed by using a gas chromatograph equipped with a programmed temperature vaporization injector (PTV). Univariate and multivariate approaches were exploited in order to optimize the parameters affecting the MEPS extraction and the PTV injection of the analytes into the gas chromatographic system. The optimal working conditions were achieved using DVB as sorbent material and acetonitrile as elution solvent. Internal standard calibration was carried out using TBP-d27 and TCEP-d12. Satisfactory values of accuracy and precision were generally obtained as well as limit of detection (2.7-99 pg/mL for tap water; 2.9-97 pg/mL for river water; 3-107 pg/mL for wastewater) and limit of quantification (0.01-0.2 ng/mL). The proposed protocol was evaluated on real case scenarios by analyzing tap water, river water and simulated wastewater samples. The developed method is not only eco-friendly due to the low use of organic solvents but also simple and automatable since the MEPS extraction procedure can be implemented in the autosampler routine. Graphical abstract The steps of the analytical protocol.

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