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1.
Life Sci Space Res (Amst) ; 41: 86-99, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38670657

RESUMO

Recent discoveries related to the habitability and astrobiological relevance of the outer Solar System have expanded our understanding of where and how life may have originated. As a result, the Icy Worlds of the outer Solar System have become among the highest priority targets for future spacecraft missions dedicated to astrobiology-focused and/or direct life detection objectives. This, in turn, has led to a renewed interest in planetary protection concerns and policies for the exploration of these worlds and has been a topic of discussion within the COSPAR (Committee on Space Research) Panel on Planetary Protection. This paper summarizes the results of those discussions, reviewing the current knowledge and the history of planetary protection considerations for Icy Worlds as well as suggesting ways forward. Based on those discussions, we therefore suggest to (1) Establish a new definition for Icy Worlds for Planetary Protection that captures the outer Solar System moons and dwarf planets like Pluto, but excludes more primitive bodies such as comets, centaurs, and asteroids: Icy Worlds in our Solar System are defined as all bodies with an outermost layer that is believed to be greater than 50 % water ice by volume and have enough mass to assume a nearly round shape. (2) Establish indices for the lower limits of Earth life with regards to water activity (LLAw) and temperature (LLT) and apply them into all areas of the COSPAR Planetary Protection Policy. These values are currently set at 0.5 and -28 °C and were originally established for defining Mars Special Regions; (3) Establish LLT as a parameter to assign categorization for Icy Worlds missions. The suggested categorization will have a 1000-year period of biological exploration, to be applied to all Icy Worlds and not just Europa and Enceladus as is currently the case. (4) Have all missions consider the possibility of impact. Transient thermal anomalies caused by impact would be acceptable so long as there is less than 10-4 probability of a single microbe reaching deeper environments where temperature is >LLT in the period of biological exploration. (5) Restructure or remove Category II* from the policy as it becomes largely redundant with this new approach, (6) Establish that any sample return from an Icy World should be Category V restricted Earth return.


Assuntos
Exobiologia , Meio Ambiente Extraterreno , Planetas , Sistema Solar , Voo Espacial , Astronave , História do Século XX
2.
Astrobiology ; 22(5): 552-567, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35325553

RESUMO

Finding evidence of life beyond Earth is the aim of future space missions to icy moons. Icy worlds with an ocean underlying the icy crust and in contact with a rocky subsurface have great astrobiological interest due to the potential for water-rock interactions that may provide a source of nutrients necessary to sustain life. Such water-rock interactions in icy moons can be indirectly investigated using analogous environments on the deep seafloor on Earth. Here, we investigate the presence of molecular and isotopic biomarkers in two submarine cold seep systems with intense rock-fluid interactions and carbon sink as carbonates with the aim of gaining understanding of potential carbon cycles in the icy worlds' oceans. Authigenic carbonates associated to cold seeps (a chimney from the Gulf of Cádiz and a clathrite from the Pacific Hydrate Ridge) were investigated for their mineralogical composition and lipid biomarker distribution. Molecular and compound-specific isotopic composition of lipid biomarkers allowed us to infer different carbonate origins in both carbonate scenarios: biogenic methane (clathrite) versus thermogenic methane together with allochthonous carbon (chimney). In the Pacific cold seep, carbonate precipitation of the clathrite was deduced to result from the anaerobic oxidation of methane by syntrophic action of methanotrophic archaea with sulfate-reducing bacteria. The distinct carbon sources (thermogenic methane, pelagic biomass, etc.) and sinks (gas clathrates, clathrite, chimney carbonates) were discussed in the light of potentially similar carbon cycling pathways in analogous icy-moon oceans. We show how the isotopic analysis of carbon may be crucial for detecting biosignatures in icy-world carbon sinks. These considerations may affect the strategy of searching for biosignatures in future space missions to the icy worlds.


Assuntos
Metano , Lua , Archaea/metabolismo , Biomarcadores/metabolismo , Carbono , Ciclo do Carbono , Carbonatos , Sedimentos Geológicos/microbiologia , Lipídeos , Metano/metabolismo , Oxirredução , Água
3.
Sci Total Environ ; 755(Pt 2): 142662, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33049523

RESUMO

Maritime Antarctica is a climate-sensitive region that has experienced a continuous increase of temperature over the last 50 years. This phenomenon accelerates glacier retreat and promotes the exposure of ice-covered surfaces, triggering physico-chemical alteration of the ground and subsequent soil formation. Here, we studied the biogeochemical composition and evolution extent of soil on three recently exposed peninsulas (Fildes, Barton and Potter) on Southwest (SW) King George Island (KGI). Nine soil samples were analyzed for their lipid biomarkers, stable isotope composition, bulk geochemistry and mineralogy. Their biomarkers profiles were compared to those of local fresh biomass of microbial mats (n = 3) and vegetation (1 moss, 1 grass, and 3 lichens) to assess their contribution to the soil organic matter (SOM). The molecular and isotopic distribution of lipids in the soil samples revealed contributions to the SOM dominated by biogenic sources, mostly vegetal (i.e. odd HMW n-alkanes distributions and generally depleted δ13C ratios). Microbial sources were also present to a lesser extent (i.e. even LMW n-alkanes and n-alkanoic acids, heptadecane, 1-alkenes, 9-octadecenoic acid, or iso/anteiso 15: 0 and 17:0 alkanoic acids). Additional contribution from petrogenic sources (bedrock erosion-derived hydrocarbons) was also considered although found to be minor. Results from mineralogy (relative abundance of plagioclases and virtual absence of clay minerals) and bulk geochemistry (low chemical weathering indexes) suggested little chemical alteration of the original geology. This together with the low content of total nitrogen and organic carbon, as well as moderate microbial activity in the soils, confirmed little edaphological development on the recently-exposed KGI surfaces. This study provides molecular and isotopic fingerprints of SOM composition in young Antarctic soils, and contributes to the understanding of soil formation and biogeochemistry in this unexplored region which is currently being affected by thermal destabilization.

4.
Space Sci Rev ; 216(8): 138, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281235

RESUMO

SuperCam is a highly integrated remote-sensing instrumental suite for NASA's Mars 2020 mission. It consists of a co-aligned combination of Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), Visible and Infrared Spectroscopy (VISIR), together with sound recording (MIC) and high-magnification imaging techniques (RMI). They provide information on the mineralogy, geochemistry and mineral context around the Perseverance Rover. The calibration of this complex suite is a major challenge. Not only does each technique require its own standards or references, their combination also introduces new requirements to obtain optimal scientific output. Elemental composition, molecular vibrational features, fluorescence, morphology and texture provide a full picture of the sample with spectral information that needs to be co-aligned, correlated, and individually calibrated. The resulting hardware includes different kinds of targets, each one covering different needs of the instrument. Standards for imaging calibration, geological samples for mineral identification and chemometric calculations or spectral references to calibrate and evaluate the health of the instrument, are all included in the SuperCam Calibration Target (SCCT). The system also includes a specifically designed assembly in which the samples are mounted. This hardware allows the targets to survive the harsh environmental conditions of the launch, cruise, landing and operation on Mars during the whole mission. Here we summarize the design, development, integration, verification and functional testing of the SCCT. This work includes some key results obtained to verify the scientific outcome of the SuperCam system.

5.
J Chromatogr A ; 1487: 153-161, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28129936

RESUMO

Increasing concerns have been raised over recent decades about human exposure to Endocrine Disrupting Chemicals (EDCs), especially about their possible effects on embryo, foetus, newborn, and child. Parabens (PBs) and ultraviolet filters (UV-filters) are prevalent EDCs widely used as additives in cosmetics and personal care products (PCPs). The objective of this study was to determine the presence of four PBs and ten UV-filters in placental tissue samples using a novel analytical method based on ultrasound-assisted extraction (UAE) and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Multivariate optimization strategies were used to accurately optimize extraction and clean-up parameters. Limits of quantification ranged from 0.15 to 0.5µgkg-1, and inter-day variability (evaluated as relative standard deviation) ranged from 3.6% to 14%. The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery percents ranged from 94.5% to 112%. The method was satisfactorily applied for the determination of the target compounds in human placental tissue samples collected at delivery from 15 randomly selected women. This new analytical procedure can provide information on foetal exposure to compounds, which has been little studied.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão , Disruptores Endócrinos/análise , Parabenos/análise , Placenta/química , Espectrometria de Massas em Tandem , Ultrassom , Técnicas de Química Analítica/normas , Feminino , Humanos , Limite de Detecção , Gravidez , Reprodutibilidade dos Testes
6.
Anal Chim Acta ; 892: 27-48, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26388473

RESUMO

In the present work, a review of the analytical methods developed in the last 15 years for the determination of endocrine disrupting chemicals (EDCs) in human samples related with children, including placenta, cord blood, amniotic fluid, maternal blood, maternal urine and breast milk, is proposed. Children are highly vulnerable to toxic chemicals in the environment. Among these environmental contaminants to which children are at risk of exposure are EDCs -substances able to alter the normal hormone function of wildlife and humans-. The work focuses mainly on sample preparation and instrumental techniques used for the detection and quantification of the analytes. The sample preparation techniques include, not only liquid-liquid extraction (LLE) and solid-phase extraction (SPE), but also modern microextraction techniques such as extraction with molecular imprinted polymers (MIPs), stir-bar sorptive extraction (SBSE), hollow-fiber liquid-phase microextraction (HF-LPME), dispersive liquid-liquid microextraction (DLLME), matrix solid phase dispersion (MSPD) or ultrasound-assisted extraction (UAE), which are becoming alternatives in the analysis of human samples. Most studies focus on minimizing the number of steps and using the lowest solvent amounts in the sample treatment. The usual instrumental techniques employed include liquid chromatography (LC), gas chromatography (GC) mainly coupled to tandem mass spectrometry. Multiresidue methods are being developed for the determination of several families of EDCs with one extraction step and limited sample preparation.


Assuntos
Disruptores Endócrinos/análise , Leite Humano/química , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/isolamento & purificação , Disruptores Endócrinos/isolamento & purificação , Feminino , Humanos , Microextração em Fase Líquida , Impressão Molecular , Parabenos/análise , Parabenos/isolamento & purificação , Fenóis/análise , Fenóis/isolamento & purificação , Ácidos Ftálicos/análise , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida , Manejo de Espécimes , Protetores Solares/análise , Protetores Solares/isolamento & purificação
7.
Artigo em Inglês | MEDLINE | ID: mdl-25942557

RESUMO

A sensitive and accurate analytical method for the determination of methyl-, ethyl-, propyl- and butylparaben and bisphenol A in human milk samples has been developed and validated. The combination of ultrasound-assisted extraction (UAE) and a simplified and rapid clean-up technique that uses sorbent materials has been successfully applied for the preparation of samples prior to ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. The analytes were extracted from freeze-dried human milk samples using acetonitrile and ultrasonic radiation (three 15-min cycles at 70% amplitude), and further cleaned-up with C18 sorbents. The most influential parameters affecting the UAE method and the clean-up steps were optimized using design of experiments. Negative electrospray ionization (ESI) in the selected reaction monitoring (SRM) mode was used for MS detection. The use of two reactions for each compound allowed simultaneous quantification and identification in one run. The analytes were separated in less than 10min. Deuterium-labeled ethylparaben-d5 (EPB-d5) and deuterium-labeled bisphenol A-d16 (BPA-d16) were used as surrogates. The limits of quantification ranged from 0.4 to 0.7ngmL(-1), while inter- and intra-day variability was under 11.1% in all cases. In the absence of certified reference materials, recovery assays with spiked samples using matrix-matched calibration were used to validate the method. Recovery rates ranged from 93.8% to 112.2%. The proposed method was satisfactorily applied for the determination of four selected parabens and bisphenol A in human milk samples obtained from nursing mothers living in the province of Granada (Spain).


Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Leite Humano/química , Parabenos/análise , Fenóis/análise , Sonicação/métodos , Espectrometria de Massas em Tandem/métodos , Compostos Benzidrílicos/química , Fracionamento Químico , Humanos , Limite de Detecção , Modelos Lineares , Parabenos/química , Fenóis/química , Reprodutibilidade dos Testes
8.
Talanta ; 134: 657-664, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25618719

RESUMO

A new sample preparation method for the determination of five benzophenone UV-filters in human breast milk has been developed. The procedure involves the lyophilization of the sample, and its subsequent extraction by ultrasound sonication using acetonitrile. In order to reduce matrix effects produced by milk components that are coextracted, mainly proteins, sugars and lipids, a further clean-up step with a mixture of dispersive-SPE sorbents, C18 and PSA, was applied. Extraction parameters were optimized using experimental design, and the compounds were detected and quantified by ultrahigh performance liquid-chromatography tandem mass spectrometry (UHPLC-MS/MS) in positive ESI mode. Analytes were separated in 10 min. BP-d10 was used as internal standard. The limits of detection (LODs) were between 0.1 and 0.2 ng mL(-1), and the limits of quantification (LOQs) were between 0.3 and 0.6 ng mL(-1) for the target analytes. The inter- and intra-day variability was <12%. The method was validated using matrix-matched calibration and recovery assays with spiked samples. Recovery rates were between 90.9 and 109.5%. The method was successfully applied for the determination of these compounds in human milk samples collected from volunteers lactating mothers with no known occupational exposure to these compounds who live in the province of Granada (Spain). The analytical method developed here may be useful for the development of more in-depth studies on the prenatal exposure and biomonitoring of these commonly used UV-filters.


Assuntos
Benzofenonas/análise , Leite Humano/química , Protetores Solares/análise , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Ultrassom
9.
J Chromatogr A ; 1371: 39-47, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25456585

RESUMO

In recent decades, the industrial development has resulted in the appearance of a large amount of new chemicals that are able to produce disorders in the human endocrine system. These substances, so-called endocrine disrupting chemicals (EDCs), include many families of compounds, such as parabens and benzophenone-UV filters. Taking into account the demonstrated biological activity of these compounds, it is necessary to develop new analytical procedures to assess the exposure in order to establish, in an accurate way, relationships between EDCs and harmful health effects in population. In the present work, a new method based on a simplified sample treatment by matrix solid phase dispersion (MSPD) followed by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis, is validated for the determination of four parabens (methyl-, ethyl-, propyl- and butylparaben) and six benzophenone-UV filters (benzophenone-1, benzophenone-2, benzophenone-3, benzophenone-6, benzophenone-8 and 4-hydroxybenzophenone) in human placental tissue samples. The extraction parameters were accurately optimized using multivariate optimization strategies. Ethylparaben ring-13C6 and benzophenone-d10 were used as surrogates. The found limits of quantification ranged from 0.2 to 0.4 ng g(-1) and inter-day variability (evaluated as relative standard deviation) ranged from 5.4% to 12.8%. The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery rates ranged from 96% to 104%. The method was satisfactorily applied for the determination of compounds in human placental tissue samples collected at the moment of delivery from 10 randomly selected women.


Assuntos
Benzofenonas/análise , Parabenos/análise , Placenta/química , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Limite de Detecção , Gravidez , Espectrometria de Massas em Tandem/métodos
10.
Rev. ing. bioméd ; 8(16): 26-32, jul.-dic. 2014. graf
Artigo em Espanhol | LILACS | ID: lil-769155

RESUMO

En este trabajo se modificó la superficie de un sustrato de oro usando la técnica Dip Pen Nanolithography (DPN) y dos tipos de puntas. Los patrones creados por el cantilever A-Frame, AF, son más homogéneos que los Diving Board, DB, esto puede deberse a que la punta DB presenta una mayor concentración de tinta que la AF, al presentar una forma rectangular hay más concentración de esfuerzos en las esquinas del rectángulo y de la punta, por tanto se tienen más opciones de presentar una adhesión de la tinta a las esquinas y una vez se empieza con el proceso de creación del patrón se desprenda la tinta en el sustrato, depositando una mayor cantidad de ella. Por otro lado, el cantilever AF presenta una forma triangular y cuenta con una única zona en la cual se concentran los esfuerzos y donde la tinta queda en exceso.


In this work the effect of two types of tips A and M, over the patterns made on a gold substrate was explored. The patterns were built with a nanolithography, acrylic ink and gold substrate, disposing each tip with a triangular shape cantilever A-Frame (AF) on one side and a rectangular Dibbing Board (DB) cantilever on the other side. The patterns created by AF are more homogeneous than DB, this may be due to the rectangular shape of the DB which presents more ink concentration, because having a rectangular shape concentrates stress in the borders and the tip, having more possibilities to present ink adhesion in the borders of the cantilever and once the process begins with the creation of the pattern the ink merges with the substrate, depositing higher amount of ink in contrast with AF because it's triangular shape counts with only one zone where the stress focuses which leads to causes ink surplus.


Neste trabalho são alteradas a superfície de um substrato de ouro utilizando a técnica de dip pen nanolithography (DPN) e dois tipos de pontas. Os padrões criados pelo cantilever A-Frame, AF, são mais homogêneas do que divingboard, DB, esta pode ser a ponta DB tem uma maior concentração de tinta do que a AF, ao pressentar uma forma retangular se tem mais concentração de esforços nos cantos do retângulo e ponta, por isso você tem mais opções para apresentar uma aderência da tinta para os cantos e uma vez que você iniciar o processo de criação do padrão se desprenda a tinta é aparente no substrato, depositando uma maior quantidade de ela. Por outro lado, cantilever AF apresenta uma forma triangular e tem uma única área em que se concentram os esforços e onde a tinta em excesso.

11.
Talanta ; 130: 561-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25159447

RESUMO

In recent decades, in parallel to industrial development, a large amount of new chemicals have emerged that are able to produce disorders in human endocrine system. These groups of substances, so-called endocrine disrupting chemicals (EDCs), include many families of compounds, such as parabens, benzophenone-UV filters and bisphenols. Given the demonstrated biological activity of those compounds, it is necessary to develop new analytical procedures to evaluate the exposure with the final objective of establishing, in an accurate way, relationships between EDCs concentrations and the harmful health effects observed in population. In the present work, a method based on a simplified sample treatment involving steps of precipitation, evaporation and clean-up of the extracts with C18 followed by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis for the determination of bisphenol A and its chlorinated derivatives (monochloro-, dichloro-, trichloro- and tetrachlorobisphenol A), parabens (methyl-, ethyl-, propyl- and butylparaben) and benzophenone-UV filters (benzophenone -1,-2, -3, -6, -8 and 4-hydroxybenzophenone) in human breast milk samples is proposed and validated. The limits of detections found ranged from 0.02 to 0.05 ng mL(-1). The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery rates ranged from 91% to 110% and the precision (evaluated as relative standard deviation) was lower than 15% for all compounds, being within the acceptable limits for the selected bioanalytical method validation guide. The method was satisfactorily applied for the determination of these compounds in human breast milk samples collected from 10 randomly selected women.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Disruptores Endócrinos/análise , Disruptores Endócrinos/química , Leite Humano/química , Espectrometria de Massas em Tandem/métodos , Calibragem , Disruptores Endócrinos/isolamento & purificação , Feminino , Humanos , Limite de Detecção
12.
Talanta ; 129: 209-18, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25127586

RESUMO

The population is continuously exposed to endocrine disrupting chemicals (EDCs). This has influenced an increase in diseases and syndromes that are more frequent nowadays. Therefore, it is necessary to develop new analytical procedures to evaluate the exposure with the ultimate objective of establishing, in an accurate way, relationships between EDCs and harmful health effects. In the present work, a new method based on a sample treatment by dispersive liquid-liquid microextraction (DLLME) for the extraction of six parabens (methyl-, ethyl-, isopropyl-, propyl-, isobutyl and butylparaben), six benzophenones (benzophenone-1, benzophenone-2, benzophenone-3, benzophenone-6, benzophenone-8 and 4-hydroxybenzophenone) and two bisphenols (bisphenol A and bisphenol S) in human urine samples, followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis is proposed. An enzymatic treatment allows determining the total content of the target EDCs. The extraction parameters were accurately optimized using multivariate optimization strategies. Ethylparaben ring-(13)C6 and bisphenol A-d16 were used as surrogates. Found limits of quantification ranging from 0.2 to 0.5 ng mL(-1) and inter-day variability (evaluated as relative standard deviation) ranging from 2.0% to 14.9%. The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery rates ranged from 94% to 105%. A good linearity, for concentrations up to 300 ng mL(-1) for parabens and 40 ng mL(-1) for benzophenones and bisphenols, respectively, was obtained. The method was satisfactorily applied for the determination of target compounds in human urine samples from 20 randomly selected individuals.


Assuntos
Disruptores Endócrinos/química , Disruptores Endócrinos/urina , Microextração em Fase Líquida/métodos , Calibragem , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Modelos Lineares , Masculino , Parabenos/química , Reprodutibilidade dos Testes , Sais/química , Espectrometria de Massas em Tandem/métodos , Urinálise/métodos
13.
Talanta ; 129: 448-58, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25127618

RESUMO

Personal care products (PCPs) are organic chemicals widely used in everyday human life. Nowadays, preservatives, UV-filters, antimicrobials and musk fragrances are widely used PCPs. Different studies have shown that some of these compounds can cause adverse health effects, such as genotoxicity, which could even lead to mutagenic or carcinogenic effects, or estrogenicity because of their endocrine disruption activity. Due to the absence of official monitoring protocols, there is an increasing demand of analytical methods that allow the determination of those compounds in human samples in order to obtain more information regarding their behavior and fate in the human body. The complexity of the biological matrices and the low concentration levels of these compounds make necessary the use of advanced sample treatment procedures that afford both, sample clean-up, to remove potentially interfering matrix components, as well as the concentration of analytes. In the present work, a review of the more recent analytical methods published in the scientific literature for the determination of PCPs in human fluids and tissue samples, is presented. The work focused on sample preparation and the analytical techniques employed.


Assuntos
Disruptores Endócrinos/análise , Compostos Orgânicos/análise , Conservantes Farmacêuticos/análise , Protetores Solares/análise , Anti-Infecciosos Locais/análise , Benzofenonas/análise , Líquidos Corporais/química , Desinfetantes/análise , Feminino , Humanos , Extração Líquido-Líquido , Masculino , Leite Humano/química , Perfumes , Sêmen/química , Soro/química , Extração em Fase Sólida , Raios Ultravioleta , Urinálise
14.
J Chromatogr A ; 1349: 69-79, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-24861790

RESUMO

In the present work, two specific, accurate and sensitive methods for the determination of endocrine disrupting chemicals (EDCs) in human breast milk are developed and validated. Bisphenol A and its main chlorinated derivatives, five benzophenone-UV filters and four parabens were selected as target analytes. The method involves a stir-bar sorptive extraction (SBSE) procedure followed by a solvent desorption prior to GC-MS/MS or UHPLC-MS/MS analysis. A derivatization step is also necessary when GC analysis is performed. The GC column used was a capillary HP-5MS with a run time of 26min. For UHPLC analysis, the stationary phase was a non-polar Acquity UPLC(®) BEH C18 column and the run time was 10min. In both cases, the analytes were detected and quantified using a triple quadrupole mass spectrometer (QqQ). Quality parameters such as linearity, accuracy (trueness and precision), sensitivity and selectivity were examined and yielded good results. The limits of quantification (LOQs) ranged from 0.3 to 5.0ngmL(-1) for GC and from 0.2 to 1.0ngmL(-1) for LC. The relative standard deviation (RSD) was lower than 15% and the recoveries ranged from 92 to 114% in all cases, being slightly unfavorable the results obtained with LC. The methods were satisfactorily applied for the determination of target compounds in human milk samples from 10 randomly selected women.


Assuntos
Técnicas de Química Analítica/métodos , Disruptores Endócrinos/análise , Cromatografia Gasosa-Espectrometria de Massas , Leite Humano/química , Compostos Benzidrílicos/análise , Benzofenonas/análise , Técnicas de Química Analítica/normas , Humanos , Parabenos/análise , Fenóis/análise , Reprodutibilidade dos Testes
15.
Anal Bioanal Chem ; 406(15): 3773-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24710638

RESUMO

In the present work, a new method based on a sample treatment by dispersive liquid-liquid microextraction (DLLME) for the extraction of six bisphenols (bisphenol A, bisphenol S, and monochloro-, dichloro-, trichloro-, and tetrachlorobisphenol A), four parabens (methyl-, ethyl-, propyl-, and butylparaben), and six benzophenones (benzophenone-1, benzophenone-2, benzophenone-3, benzophenone-6, benzophenone-8, and 4-hydroxybenzophenone) in human urine samples, followed by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis, is validated. An enzymatic treatment allows determining the total content of the target EDCs. The extraction parameters were accurately optimized using multivariate optimization strategies. Ethylparaben ring-(13)C6, benzophenone-d10, and bisphenol A-d16 were used as surrogates. Limits of quantification ranging from 0.1 to 0.6 ng mL(-1) and interday variabilities (evaluated as relative standard deviations) from 2.0 to 13.8% were obtained. The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery rates ranged from 94 to 106%. A good linearity, for concentrations up to 300 ng mL(-1) for parabens and 40 ng mL(-1) for benzophenones and bisphenols, was also obtained. The method was satisfactorily applied for the determination of target compounds in human urine samples from 20 randomly selected individuals.


Assuntos
Compostos Benzidrílicos/química , Cloro/química , Parabenos/análise , Fenóis/química , Urinálise/métodos , Benzofenonas/química , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Feminino , Humanos , Concentração de Íons de Hidrogênio , Microextração em Fase Líquida , Masculino , Parabenos/química , Reprodutibilidade dos Testes , Sais , Solventes , Espectrometria de Massas em Tandem
16.
Talanta ; 121: 97-104, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24607115

RESUMO

Benzophenone-UV filters (BP-UV filters) are extensively used in cosmetics products to avoid damaging effects of UV radiation. Despite their low toxicity, many research papers indicate that BP-UV filters are weak endocrine disruptors (EDCs). There are clear relationships between BP-UV filters exposure and several health disorders such as carcinogenesis and malformations observed in animals. In the present work, a new sample treatment procedure by dispersive liquid-liquid microextraction (DLLME) is proposed for the extraction of six BPs, namely benzophenone-1 (BP-1), benzophenone-2 (BP-2), benzophenone-3 (BP-3), benzophenone-6 (BP-6), benzophenone-8 (BP-8) and 4-hydroxybenzophenone (4-OH-BP), in human serum samples, followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis. The method involves an enzymatic treatment to quantify the total content (free plus conjugated species) of BP-UV filters in serum. The extraction parameters were accurately optimized using multivariate optimization approach. Benzophenone-d10 (BP-d10) was used as surrogate. Limits of quantification (LOQs) ranged from 0.4 to 0.9 ng mL(-1) and inter-day precision (evaluated as relative standard deviation) ranged from 1.9% to 13.1%. The method was validated using matrix-matched calibration and a recovery assay. Recovery rates for spiked samples ranged from 97% to 106%, and acceptable linearity was obtained up to concentrations of 40 ng mL(-1). The method was applied to the determination of the target compounds in human serum samples from 20 randomly selected anonymous individuals.


Assuntos
Benzofenonas/sangue , Cromatografia Líquida/métodos , Microextração em Fase Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Raios Ultravioleta , Humanos , Reprodutibilidade dos Testes
17.
Mar Pollut Bull ; 79(1-2): 107-13, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24398419

RESUMO

Alcohol sulfates (AS) and alcohol ethoxysulfates (AES) are all High Production Volume and 'down-the-drain' chemicals used globally in detergent and personal care products, resulting in low levels ultimately released to the environment via wastewater treatment plant effluents. They have a strong affinity for sorption to sediments. Almost 50% of Tenerife Island surface area is environmentally protected. Therefore, determination of concentration levels of AS/AES in marine sediments near wastewater discharge points along the coast of the Island is of interest. These data were obtained after pressurized liquid extraction and liquid chromatography-tandem mass spectrometry analysis. Short chains of AES and especially of AS dominated the homologue distribution for AES. The Principal Components Analysis was used. The results showed that the sources of AS and AES were the same and that both compounds exhibit similar behavior. Three different patterns in the distribution for homologues and ethoxymers were found.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Sulfatos/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Espanha , Eliminação de Resíduos Líquidos , Águas Residuárias/estatística & dados numéricos
18.
Astrobiology ; 13(10): 991-1004, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24143869

RESUMO

In this paper, we provide a detailed review of Ganymede's characteristics that are germane to any consideration of its planetary protection requirements. Ganymede is the largest moon in our solar system and is the subject of one of the main science objectives of the JUICE mission to the jovian system. We explore the probability of the occurrence of potentially habitable zones within Ganymede at present, including those both within the deep liquid ocean and those in shallow liquid reservoirs. We consider the possible exchange processes between the surface and any putative habitats to set some constraints on the planetary protection approach for this moon. As a conclusion, the "remote" versus "significant" chance of contamination will be discussed, according to our current understanding of this giant icy moon. Based on the different estimates we investigate here, it appears extremely unlikely that material would be exchanged downward through the upper icy layer of Ganymede and, thus, bring material into the ocean over timescales consistent with the survival of microorganisms.


Assuntos
Meio Ambiente Extraterreno , Júpiter , Exobiologia , Gelo , Temperatura
19.
Talanta ; 115: 606-15, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054639

RESUMO

A novel and successful method has been developed for the identification and quantification of alcohol sulfates (AS) homologues and alcohol ethoxysulfates (AES) ethoxymers in marine and river sediment samples. The method involves the extraction of 5.00 g of dry sample with methanol using pressurized liquid extraction (PLE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). 2-Octylbenzene sulfonic acid sodium salt (2ØC8-LAS) was used as internal standard. The analytical methods were applied to marine sediments collected from the coast of Almeria (South-east Spain) and river sediments collected from the Monachil river (Granada, South-east Spain). For AS homologues, the found limits of detection were 0.04-0.08 µg g(-1) for marine and river sediments. For AES ethoxymers, the found limits of detection were 0.03-0.09 µg g(-1) and 0.06-0.22 µg g(-1) for marine and river sediments, respectively. The highest concentrations of AS and AES were found in river sediment samples. Significant differences were also observed between the behavior of short-chain compounds (C12) and long-chain compounds (C14 to C18). The influence of the physic-chemical properties of water on the occurrence of these compounds was also evaluated, and differences between long- and short-chain compounds were also observed. Additionally, principal components analyses were carried out in order to study the relationship between variables and to evaluate the sources of data variability and behavior patterns. Finally, important conclusions were drawn regarding the environmental behavior of AS and AES.


Assuntos
Álcoois/análise , Sedimentos Geológicos/química , Sulfatos/análise , Derivados de Benzeno/análise , Cromatografia Líquida , Limite de Detecção , Extração Líquido-Líquido , Análise de Componente Principal , Padrões de Referência , Rios , Água do Mar , Espanha , Espectrometria de Massas em Tandem
20.
Artigo em Inglês | MEDLINE | ID: mdl-24004914

RESUMO

UV-filters are widely used in many personal care products and cosmetics. Recent studies indicate that some organic UV-filters can accumulate in biota and act as endocrine disruptors, but there are few studies on the occurrence and fate of these compounds in humans. In the present work, a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to assess the presence of six UV-filters in current use (benzyl salicylate, phenyl salicylate, octyl salicylate, homosalate, 3-(4-methylbenzylidene) camphor, and 3-benzylidene camphor) in human placental tissue is proposed. The method involves the extraction of the analytes from the samples using ethyl acetate, followed by a clean-up step using centrifugation prior to their quantification by LC-MS/MS using an atmospheric pressure chemical ionization (APCI) interface. Bisphenol A-d16 was used as surrogate for the determination of benzyl salicylate, phenyl salicylate, octyl salicylate and homosalate in negative mode and benzophenone-d10, was used as surrogate for the determination of 3-(4-methylbenzylidene) camphor and 3-benzylidene camphor in positive mode. The found limits of detection ranged from 0.4 to 0.6ngg(-1) and the limits of quantification ranged from 1.3 to 2.0ngg(-1), while variability was under 13.7%. Recovery rates for spiked samples ranged from 97% to 104%. Moreover, the interactions of these compounds with the human estrogen receptor alpha (hERα) and androgen receptor (hAR), using two in vitro bioassays based on reporter gene expression and cell proliferation assessment, were also investigated. All tested compounds, except benzyl salicylate and octyl salicylate, showed estrogenic activity in the E-Screen bioassay whereas only homosalate and 3-(4-methylbenzylidene) camphor were potent hAR antagonists. Although free salicylate derivatives and free camphor derivatives were not detected in the human placenta samples analyzed, the observed estrogenic and anti-androgenic activities of some of these compounds support the analysis of their occurrence and their role as endocrine disrupters in humans.


Assuntos
Cânfora/análogos & derivados , Estrogênios/análise , Placenta/química , Salicilatos/análise , Protetores Solares/análise , Cânfora/análise , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida/métodos , Relação Dose-Resposta a Droga , Feminino , Humanos , Luciferases/metabolismo , Células MCF-7 , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos
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