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1.
Heliyon ; 10(9): e29767, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38698991

RESUMO

A methodological approach based on rare earth elements analysis was developed to observe human activities in the stratigraphic sequence of Alagankulam. The site was one of the main ancient ports in south-eastern India and one of the transoceanic connecting points between East and West during the Classical Period. The sampled sediments where collected from vertical profiles, areas with traces of firing activities and filled deposits. Major, minor and trace element concentrations were measured by the means of spectroscopic and spectrometric techniques. Data from multielemental analysis were then cross-referenced together with archaeological evidence to map the variability within the site and its association with the detected anthropic activities. The matching of the interpretation of the archaeological record and the analytical data has allowed a combined mapping of visible and invisible traces of human activities in the site, giving a deeper insight of the Alagankulam occupational history.

2.
PLoS One ; 18(8): e0289378, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37610984

RESUMO

The casts of Pompeii bear witness to the people who died during the Vesuvius 79 AD eruption. However, studies on the cause of death of these victims have not been conclusive. A previous important step is the understanding of the post-depositional processes and the impact of the plaster in bones, two issues that have not been previously evaluated. Here we report on the anthropological and the first chemical data obtained from the study of six casts from Porta Nola area and one from Terme Suburbane. A non-invasive chemical analysis by portable X-ray fluorescence was employed for the first time on these casts of Pompeii to determine the elemental composition of the bones and the plaster. Elemental profiles were determined providing important data that cross-referenced with anthropological and stratigraphic results, are clearly helpful in the reconstruction of the perimortem and post-mortem events concerning the history of these individuals. The comparative analyses carried out on the bone casts and other collections from burned bones of the necropolis of Porta Nola in Pompeii and Rome Sepolcreto Ostiense, and buried bones from Valencia (Spain), reveal the extent of high temperature alteration and post-depositional plaster contamination. These factors make bioarchaeological analyses difficult but still allow us to support asphyxia as the likely cause of death.


Assuntos
Lepidópteros , Contenções , Humanos , Animais , Antropologia , Asfixia , Cromatografia Gasosa , Contaminação de Medicamentos , Nitroarginina
3.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070266

RESUMO

The purpose of this work is to describe the use of Fibrin-Plasma Rich in Growth Factors (PRGF) membranes for the treatment of a rabbit alkali-burn lesion. For this purpose, an alkali-burn lesion was induced in 15 rabbits. A week later, clinical events were evaluated and rabbits were divided into five treatment groups: rabbits treated with medical treatment, with a fibrin-PRGF membrane cultured with autologous or heterologous rabbit Limbal Epithelial Progenitor Cells (LEPCs), with a fibrin-PRGF membrane in a Simple Limbal Epithelial Transplantation and with a fibrin-PRGF membrane without cultured LEPCs. After 40 days of follow-up, corneas were subjected to histochemical examination and immunostaining against corneal or conjunctival markers. Seven days after alkali-burn lesion, it was observed that rabbits showed opaque cornea, new blood vessels across the limbus penetrating the cornea and epithelial defects. At the end of the follow-up period, an improvement of the clinical parameters analyzed was observed in transplanted rabbits. However, only rabbits transplanted with cultured LEPCs were positive for corneal markers. Otherwise, rabbits in the other three groups showed positive staining against conjunctival markers. In conclusion, fibrin-PRGF membrane improved the chemically induced lesions. Nonetheless, only fibrin-PRGF membranes cultured with rabbit LEPCs were able to restore the corneal surface.


Assuntos
Queimaduras Químicas , Células Epiteliais , Queimaduras Oculares , Fibrina/farmacologia , Plasma , Transplante de Células-Tronco , Células-Tronco , Animais , Autoenxertos , Queimaduras Químicas/metabolismo , Queimaduras Químicas/patologia , Queimaduras Químicas/terapia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/transplante , Queimaduras Oculares/metabolismo , Queimaduras Oculares/patologia , Queimaduras Oculares/terapia , Limbo da Córnea/metabolismo , Limbo da Córnea/patologia , Coelhos , Células-Tronco/metabolismo , Células-Tronco/patologia
4.
J Anal Toxicol ; 45(4): 331-336, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-32685974

RESUMO

A procedure has been developed for the determination of third-generation synthetic cannabinoids in oral fluid samples by using a semi-automated microextraction by packed sorbent (MEPS) procedure and gas chromatography-mass spectrometry (GC-MS) determination. Five synthetic cannabinoids were employed as model compounds 5F-ADB, MMB-CHMICA, THJ-2201, CUMYL-4CN-BINACA and MDMB-CHMCZCA. The most adequate operative conditions for MEPS were evaluated giving quantitative recoveries, from 89 to 124%, in synthetic and field saliva samples spiked with 125 and 250 µg/L of the studied cannabinoids, with the exception of MDMB-CHMCZCA in field saliva samples that provided slightly lower recoveries from 62 to 66%. A high sensitivity was obtained for the proposed MEPS-GC-MS procedure with limits of detection from 10 to 20 µg/L. The obtained results demonstrate the high potential of MEPS-GC-MS combination for semi-automated, selective and sensitive determination of synthetic cannabinoids in oral fluid samples.


Assuntos
Canabinoides , Drogas Ilícitas , Canabinoides/análise , Cromatografia Gasosa-Espectrometria de Massas , Saliva/química
5.
Environ Pollut ; 268(Pt B): 115646, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038574

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are pollutants produced during incomplete combustion of organic matter and several industrial processes. Humans can be exposed to PAHs through ingestion of food, inhalation of tobacco smoke or polluted air, and dermal contact, causing immunologic, developmental, and reproductive problems. In the present research, eleven metabolites of PAHs were analyzed in the urine of 110 lactating women living in Spain (2015). PAH metabolites were extracted from the urine samples by liquid-liquid extraction and their determination was performed by liquid chromatography coupled to tandem mass spectrometry. In addition, information on lifestyle and dietary habits of the participants was collected using a questionnaire. All the PAH metabolites were detected in more than 70% of the samples, except for 3-hydroxybenzo(a)pyrene which was detected in less than 1% of the samples. The highest urinary levels were found for naphthalene metabolites, with geometric means of 0.8 (1-hydroxynaphthalene) and 7.1 ng ml-1 (2-hydroxynaphthalene). The statistical analysis showed that smoking status, as well as the ingestion of certain food groups (vegetables, cereals, oils and fats, smoked fish and coffee), were the main influencing factors of exposure to PAHs. The estimated daily intake (EDI) was calculated for naphthalene, fluorene, phenanthrene, and pyrene, ranging from 6 to 1522 ng kg-1·day-1. The non-cancer risk associated to PAH exposure was estimated, showing hazard quotients (HQs) and hazard indexes (HIs) below 1. Therefore, it did not reveal a significant health risk for Spanish women due to PAH exposure.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Animais , Monitoramento Biológico , Monitoramento Ambiental , Feminino , Humanos , Lactação , Estilo de Vida , Mães , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Espanha
6.
Chemosphere ; 255: 127003, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679629

RESUMO

In this study, we assessed the presence of 14 phthalate metabolites in the urine of 104 lactating mothers from Valencia (Spain) who took part in the human biomonitoring project BETTERMILK. Nine of the metabolites studied showed detection frequencies >80%, whereas the rest of the metabolites presented low detection frequencies (<5%). The concentrations ranged from

Assuntos
Monitoramento Biológico , Aleitamento Materno/estatística & dados numéricos , Exposição Materna/estatística & dados numéricos , Ácidos Ftálicos , Adulto , Coleta de Dados , Dietilexilftalato , Exposição Ambiental/análise , Poluentes Ambientais/metabolismo , Feminino , Humanos , Lactação , Mães , Embalagem de Produtos , Medição de Risco , Espanha
7.
Sci Total Environ ; 699: 134385, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31678881

RESUMO

The aim of the present study was to assess the exposure to pesticides in urine from Spanish lactating mothers (n = 116). Six nonspecific (dialkyl phosphates) and 20 specific metabolites of organophosphate pesticides (OPs), herbicides and pyrethroids were analyzed. The most frequently detected biomarkers were diethyl phosphate, p-nitrophenol, 3,5,6-trichloro-2-pyridinol and 3-phenoxybenzoic acid, whose geometric means were 1.9 ng·mL-1, 0.8 ng·mL-1, 1.5 ng·mL-1 and 1.4 ng·mL-1, respectively. Herbicide metabolites were the least frequently detected biomarkers with detection frequencies between 0% (2,4,5-Trichlorophenoxyacetic acid) and 22% (2,4-Dichlorophenoxyacetic acid). Multiple regression analyses showed that the closeness to a farming activity, the place of residence and the presence of garden/plants at home were some of the most important contributors to urinary levels of pesticide metabolites. Estimated daily intake (EDI), hazard quotient (HQ) and hazard index (HI) were obtained in order to interpret urinary levels of the most frequently detected pesticide metabolites in a risk assessment context. The highest EDIs were obtained for chlorpyrifos (0.40-1.14 µg·kg bw-1·day-1) and deltamethrin (0.34-4.73 µg·kg bw-1·day-1). The calculated HQ for chlorpyrifos, dimethoate, parathion and deltamethrin ranged from 0.01 to 0.47, and HI for OPs ranged from 0.09 to 0.33 showing that apparently there were low health risks due to the exposure to these pesticides in this group of Spanish breastfeeding women.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/urina , Exposição Materna/estatística & dados numéricos , Praguicidas/urina , Adulto , Feminino , Humanos , Lactação , Mães
8.
Chemosphere ; 240: 124829, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563722

RESUMO

In this study, we assessed the presence of four parabens in human milk of 120 mothers from Valencia (Spain) which took part in a human biomonitoring project (BETTERMILK). The detection frequency ranges of parabens were 41-60% and 61-89% for unconjugated- and total (unconjugated + conjugated)-parabens, respectively. The concentrations ranged from

Assuntos
Monitoramento Biológico/métodos , Aleitamento Materno/métodos , Leite Humano/química , Parabenos/química , Feminino , Humanos , Lactente , Recém-Nascido
9.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1130-1131: 121810, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669632

RESUMO

In this study a fast and sensitive method was developed for the quantitative determination of six dialkyl phosphates (DAPs) in human urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proposed methodology was based on liquid-liquid extraction (LLE) with diethyl ether and ethyl acetate using MgSO4 and NaCl, followed by liquid chromatography and mass spectrometry detection in the selected reaction mode (SRM) with negative electrospray ionization (ESI-). Detection settings were optimized by design of experiments (DoE). Dibutyl phosphate (DBP) was used as internal standard. Several criteria established in the SANTE/11813/2017 guidance document for pesticide residues and analysis in food and feed were used to validate the suggested method: recoveries (R %) between 70 and 120% and coefficients of variation (CV %) ≤ 20%. The procedural limit of quantification (LoQ) was 0.50 ng mL-1 for the six DAPs. The R% and CV% ranges were 82-117% and 3-20%, respectively. In total, 20 spot urine samples from lactating mothers were satisfactorily analyzed by the proposed analytical strategy.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Compostos Organofosforados/urina , Resíduos de Praguicidas/urina , Fosfatos/urina , Espectrometria de Massas em Tandem/métodos , Adulto , Feminino , Humanos , Lactação , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Adulto Jovem
10.
Int J Anal Chem ; 2019: 1917369, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118948

RESUMO

Mass spectrometer parameters such as Resolving Power, type of fragmentation, and mass calibration mode were optimized in the analysis of 24 pesticide metabolites in human urine using Ultra-High Pressure Liquid Chromatography coupled to Orbitrap High-Resolution Mass Spectrometer (UHPLC-HRMS). The best results were achieved with a Resolving Power of 25,000 FWHM and by applying Collision Induced Dissociation fragmentation mode (40 eV).

11.
Rev Esp Cardiol (Engl Ed) ; 72(12): 1020-1030, 2019 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30935899

RESUMO

INTRODUCTION AND OBJECTIVES: We describe the results for Spain of the Second European Cardiac Resynchronization Therapy Survey (CRT-Survey II) and compare them with those of the other participating countries. METHODS: We included patients undergoing CRT device implantation between October 2015 and December 2016 in 36 participating Spanish centers. We registered the patients' baseline characteristics, implant procedure data, and short-term follow-up information until hospital discharge. RESULTS: Implant success was achieved in 95.9%. The median [interquartile range] annual implantation rate by center was significantly lower in Spain than in the other participating countries: 30 implants/y [21-50] vs 55 implants/y [33-100]; P=.00003. In Spanish centers, there was a lower proportion of patients ≥ 75 years (27.9% vs 32.4%; P=.0071), a higher proportion in New York Heart Association functional class II (46.9% vs 36.9%; P <.00001), and a higher percentage with electrocardiographic criteria of left bundle branch block (82.9% vs 74.6%; P <.00001). The mean length of hospital stay was significantly lower in Spanish centers (5.8±8.5 days vs 6.4±11.6; P <.00001). Spanish patients were more likely to receive a quadripolar LV lead (74% vs 56%; P <.00001) and to be followed up by remote monitoring (55.8% vs 27.7%; P <.00001). CONCLUSIONS: The CRT-Survey II shows that, compared with other participating countries, fewer patients in Spain aged ≥ 75 years received a CRT device, while more patients were in New York Heart Association functional class II and had left bundle branch block. In addition, the length of hospital stay was shorter, and there was greater use of quadripolar LV leads and remote CRT monitoring.


Assuntos
Arritmias Cardíacas/terapia , Terapia de Ressincronização Cardíaca/estatística & dados numéricos , Inquéritos e Questionários , Idoso , Arritmias Cardíacas/epidemiologia , Eletrocardiografia , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Retrospectivos , Espanha/epidemiologia
12.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1114-1115: 154-166, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30890302

RESUMO

For the first time, a multiresidue, sensitive and high throughput method for determination of bisphenol A, F and S and 4 parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in human breast milk was developed. The proposed method includes an extraction and clean-up procedure based on QuEChERS methodology followed by liquid chromatography coupled to triple quadrupole mass spectrometry determination. Negative atmospheric pressure chemical ionization in the selected reaction monitoring mode was used for mass detection. During the method validation the recoveries varied between 83 and 115% with a precision lower than 20% for all analytes using spiked levels from 0.1 to 50 ng mL-1. The LOQ was 0.10 ng mL-1 for most of the analytes. The proposed method was successfully applied for the determination of these compounds in 10 breast milk samples from volunteer lactating mothers from the Valencian region (Spain). Among parabens, methyl paraben presented the highest detection frequency (80%) with a concentration range of 0.11-7.00 ng mL-1, while bisphenol A was detected more frequently than BPF and BPS (80% of detection frequency) with concentrations ranging from 0.13 to 1.62 ng mL-1.


Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Leite Humano/química , Parabenos/análise , Fenóis/análise , Adulto , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Sulfonas/análise
13.
Sci Total Environ ; 668: 797-805, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-30870748

RESUMO

The present study addresses the presence of bisphenols A (BPA) and its analogs bisphenol F (BPF) and S (BPS) in milk of 120 mothers living in Valencia (Spain) and participating in the BETTERMILK project (year 2015). We also studied the factors that could influence the BPA levels and estimated the exposure and the risk for breast fed infants. The frequency of detection of total (conjugated + unconjugated) and unconjugated-BPA were 83% and 77%, with a geometric mean of 0.29 ng/mL and 0.15 ng/mL, respectively. The frequency of detection was much lower for total-BPF (22%) and total-BPS (1.1%). The place of residence of the mother and the use of personal care products showed significant association with BPA concentrations. The estimated daily intake of total-BPA for breastfed infants amounted to a geometric mean of 0.04 µg/kg bw and a 95th percentile of 1.0 µg/kg bw, below the tolerable daily intake of 4 µg/kg bw-day established by EFSA. To our knowledge, this is the largest biomonitoring study of bisphenols in human milk in Europe.


Assuntos
Compostos Benzidrílicos/metabolismo , Aleitamento Materno/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Exposição Materna/estatística & dados numéricos , Leite Humano/metabolismo , Fenóis/metabolismo , Adulto , Monitoramento Ambiental , Feminino , Humanos , Lactente , Mães , Espanha , Sulfonas/metabolismo
14.
Sci Total Environ ; 619-620: 1014-1021, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29734579

RESUMO

A calibration chamber has been designed and employed for the simple and easy determination of uptake sampling rate (RS) of volatile organic compounds (VOCs) from air using passive samplers. A flow of clean air was continuously spiked, at a constant VOC concentration, by the microinjection of a standard solution by means of a T-type tube. The developed system allowed the complete evaporation at room temperature of the standard solution in acetone and the air concentration of VOCs was easily controlled by the regulation of the clean air flow, the standard solution concentration and its flow. Active sampling was employed for monitoring the true concentration of the evaluated compounds inside the calibration chamber, using Tenax-filled desorption tubes and a low flow personal air sampling pump. Versatile, easy and rapid atmospheric monitor (VERAM) devices were employed for the passive sampling of benzene, toluene, ethylbenzene, xylenes, α-pinene, camphene, myrcene, p-cymene, and limonene from air. The RS values obtained for the passive sampling of VOCs, using the developed calibration chamber, were in the range of 1.3-16.0m3day-1 in accordance to previous calibration studies performed for VERAM samplers. The developed calibration chamber provided a continuous flow with a constant concentration of the evaluated compounds that allowed the simultaneous deployment of several samplers for a rapid establishment of RS for a passive sampler type and the easy comparison between different devices.

15.
J Forensic Leg Med ; 56: 83-89, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29609050

RESUMO

Giovanni Pico della Mirandola and Angelo Poliziano were two of the most important humanists of the Italian Renaissance. They died suddenly in 1494 and their deaths have been for centuries a subject of debate. The exhumation of their remains offered the opportunity to study the cause of their death through a multidisciplinary research project. Anthropological analyses, together with documentary evidences, radiocarbon dating and ancient DNA analysis supported the identification of the remains attributed to Pico. Macroscopic examination did not reveal paleopathological lesions or signs related to syphilis. Heavy metals analysis, carried out on bones and mummified tissues, showed that in Pico's remains there were potentially lethal levels of arsenic, supporting the philosopher's poisoning theory reported by documentary sources. The arsenic concentrations obtained from analysis of Poliziano's remains, are probably more related to an As chronic exposure or diagenetic processes rather than poisoning.


Assuntos
Intoxicação por Arsênico/história , Arsênio/análise , Osso e Ossos/química , Radioisótopos de Carbono , DNA Antigo , Exposição Ambiental/efeitos adversos , Toxicologia Forense , História do Século XV , Humanos , Itália , Masculino , Microscopia , Microscopia Eletrônica de Varredura , Múmias , Análise Espectral/métodos
16.
Microsc Microanal ; 24(2): 183-192, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29560839

RESUMO

Polistes paper wasps can be used to monitor trace metal contaminants, but the effects of pollution on the health of these insects are still unknown. We evaluated, in a south-eastern area of Spain, whether workers of Polistes dominula collected at urban and rural sites differ in health of midgut tissue and in fluctuating asymmetry, an estimate of developmental noise. We found that wasps collected at the urban sites had abundant lead (Pb)-containing spherites, which were less visible in wasps from the rural sites. Evident ultrastructural alterations in the epithelium of the midgut of the wasps collected at the urban sites included broken and disorganized microvilli, a high amount and density of heterochromatin in the nucleus of epithelial cells, cytoplasmic vacuolization and mitochondrial disruptions. Altogether, these findings suggest a negative effect on the transmembrane transport and a less efficient transcription. On the contrary, a healthy epithelium was observed in wasps from the rural sites. These differences may be preliminarily linked with levels of lead pollution, given that wasps from urban sites had double the Pb concentrations of wasps from rural sites. Level of fluctuating asymmetry was unrelated to wasp origin, thus suggesting no link between developmental noise and Pb-driven pollution.


Assuntos
Mucosa Intestinal/ultraestrutura , Vespas/anatomia & histologia , Vespas/ultraestrutura , Asas de Animais/anatomia & histologia , Animais , Cidades , Poluentes Ambientais/análise , Chumbo/análise , Espanha , Vespas/química
17.
Invest Ophthalmol Vis Sci ; 58(9): 3357-3365, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28687847

RESUMO

Purpose: Develop a silk fibroin (SF)-based artificial endothelial graft for its use in a rabbit Descemet membrane endothelial keratoplasty (DMEK). Methods: Human and rabbit artificial corneal endothelial grafts were developed through the culture of human and rabbit corneal endothelial cells (CECs) on SF films. Rabbit artificial SF endothelial grafts were transplanted in a DMEK surgery into a rabbit in vivo model. Results: SF artificial endothelial grafts showed the characteristic endothelial markers: zonula occludens (ZO-1) and Na+/K+ ATPase. In a rabbit model of DMEK surgery, SF artificial endothelial graft restored the corneal transparency and thickness at 6 week of follow-up. Anterior segment optical coherence tomography revealed the SF graft as a fully integrated component in the corneal tissue, displaying a similar corneal thickness and endothelial cell count when compared with its healthy contralateral cornea. Histologic analysis showed that the SF artificial endothelial graft was attached and integrated on the surface of the corneal stroma without a significant inflammatory reaction, and rabbit CECs consisted in a monolayer that showed their characteristic markers ZO-1 and Na+/K+ ATPase, suggesting proper intercellular junctions and cellular pump function. Conclusions: We have developed SF films with biological properties that supported the growth of rabbit and human CECs, which showed normal morphology and characteristic markers; and with mechanical properties that allowed its use in a DMEK surgery, proving its in vivo functionality in a rabbit model of endothelial dysfunction.


Assuntos
Edema da Córnea/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Endotélio Corneano/transplante , Fibroínas , Membranas Artificiais , Seda , Engenharia Tecidual , Animais , Células Cultivadas , Edema da Córnea/patologia , Modelos Animais de Doenças , Células Endoteliais/citologia , Humanos , Coelhos , Engenharia Tecidual/métodos
18.
Talanta ; 162: 428-434, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27837852

RESUMO

An innovative methodological approach has been developed for the prediction of the mineral element composition of bone remains. It is based on the use of Fourier Transform Near Infrared (FT-NIR) diffuse reflectance measurements. The method permits a fast, cheap and green analytical way, to understand post-mortem degradation of bones caused by the environment conditions on different skeletal parts and to select the best preserved bone samples. Samples, from the Late Roman Necropolis of Virgen de la Misericordia street and En Gil street located in Valencia (Spain), were employed to test the proposed approach being determined calcium, magnesium and strontium in bone remains and sediments. Coefficients of determination obtained between predicted values and reference ones for Ca, Mg and Sr were 90.4, 97.3 and 97.4, with residual predictive deviation of 3.2, 5.3 and 2.3, respectively, and relative root mean square error of prediction between 10% and 37%. Results obtained evidenced that NIR spectra combined with statistical analysis can help to predict bone mineral profiles suitable to evaluate bone diagenesis.


Assuntos
Osso e Ossos/química , Fósseis , Metais Alcalinoterrosos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Cálcio/análise , Humanos , Magnésio/análise , Reprodutibilidade dos Testes , Espanha , Estrôncio/análise
19.
Anal Chim Acta ; 952: 41-49, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28010841

RESUMO

A Nespresso© hard cap espresso machine has been employed for the quantitative extraction of polychlorinated biphenyls (PCBs) from sediments and soils. Sample extraction was performed from five grams of sample in less than 40 s, with 200 mL ethanol 40% (v/v) in water and PCBs were concentrated using stir bar sorptive extraction (SBSE) and determined by thermal desorption-gas chromatography-tandem mass spectrometry (TD-GC-MS-MS). Eleven PCB congeners (28, 52, 77, 80, 81, 101, 118, 138, 153,169, and 180) were determined in soils and sediments with limits of quantification in the 0.03-0.08 ng g-1 range. Extraction efficiency was established by the analysis of soil samples spiked with the studied PCBs at concentrations from 0.1 to 10.0 ng g-1, obtaining quantitative recoveries from 81 to 120% and an adequate precision with relative standard deviations lower than 20%. Certified reference materials and natural samples were analyzed by the proposed hard cap espresso extraction and results were compared with those provided by a reference procedure based on pressurized solvent extraction, obtaining statistically comparable results. Therefore, the use of a hard cap espresso machine in tandem with SBSE and TD-GC-MS-MS allowed a simple, sensitive and quantitative determination of PCBs.

20.
Anal Bioanal Chem ; 408(29): 8495-8503, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27734135

RESUMO

The versatile, easy, and rapid atmospheric monitor (VERAM), a passive sampler device widely used for air monitoring, was evaluated as passive sampler for the determination of 23 pesticides in water. Gas chromatography with mass spectrometry detection was employed for determination of pesticides after microwave-assisted-extraction and specific clean-up of deployed samplers. The proposed methodology reached method detection levels from 2 to 10 ng pesticide per sampler. Sampling rate (Rs) was determined for every pesticide from an uptake isotherm study performed at three different concentration levels (50, 125, and 250 ng L-1). The obtained RS values ranged from 0.06 to 0.76 L d-1. The obtained limits of detection for a 24-h passive sampling were from 4 to 50 ng L-1. The effect of water parameters, such as temperature, pH, and ionic strength, were evaluated for their effect on pesticides retention using VERAMs. Pesticide RS values were independent of the water composition and increased on increasing temperature. Finally, the VERAM uptake was compared with that obtained using classic semipermeable membrane devices (SPMDs). This study is the first precedent for the use of VERAMs as passive samplers for the adsorption and concentration of pesticides in water and it confirms the satisfactory analytical figures of merit of VERAM as passive sampler of water. Graphical Abstract Scheme of water sampling of pesticides using versatile, easy, and rapid atmospheric monitor (VERAM) passive samplers.

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