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1.
Molecules ; 23(3)2018 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-29534443

RESUMO

Tributyltin (TBT) is one of the most toxic anthropogenic compounds introduced into the marine environment. Despite its global ban in 2008, TBT is still a problem of great concern due to its high affinity for particulate matter, providing a direct and potentially persistent route of entry into benthic sediments. Bioremediation strategies may constitute an alternative approach to conventional physicochemical methods, benefiting from the microorganism's potential to metabolize anthropogenic compounds. In this work, a simple, precise and accurate static headspace gas chromatography method was developed to investigate the ability of TBT degrading microbes in sedimentary microcosms over a period of 120 days. The proposed method was validated for linearity, repeatability, accuracy, specificity, limit of detection and limit of quantification. The method was subsequently successfully applied for the detection and quantification of TBT and degradation compounds in sediment samples on day 0, 30, 60, 90 and 120 of the experiment employing the principles of green chemistry. On day 120 the concentration of TBT remaining in the microcosms ranged between 91.91 ng/g wet wt for the least effective microbial inoculant to 52.73 ng/g wet wt for the most effective microbial inoculant from a starting concentration of 100 ng/g wet wt.


Assuntos
Bactérias/crescimento & desenvolvimento , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Trialquitina/análise , Bactérias/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/isolamento & purificação , Sedimentos Geológicos/microbiologia , Química Verde , Microbiologia do Solo , Compostos de Trialquitina/isolamento & purificação
2.
Anal Bioanal Chem ; 406(12): 2993-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24577579

RESUMO

In this study, tributyltin (TBT) was extracted from marine sediment matrix with the use of pressurised solvent extraction (PSE), which uses high-temperature and -pressure conditions to increase extraction efficiency. The analyte was chromatographically resolved using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system with a pentafluorophenyl (PFP) column and a methanol/aqueous formic acid mobile phase gradient, and was detected by MS/MS as product fragments after collisionally induced dissociation (CID) of the cationic parent molecule. This study represents the first application of PSE extraction combined with LC-MS/MS analysis for the determination of TBT in sediments. The method has been validated according to the International Organisation for Standardisation (ISO) 17025:2001 and affords automated extraction of sediment samples with high-sensitivity analysis. The full method limit of detection was established as 1.25 ng Sn g(-1) with an instrument detection limit of 0.01 ng Sn g(-1). The chromatographic procedure may also be applied for the direct analysis of water matrices without the need for sample manipulation, and therefore represents a combined analytical approach for the monitoring of TBT contamination in marine or estuarine ecosystems.


Assuntos
Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Sedimentos Geológicos/análise , Espectrometria de Massas em Tandem/métodos , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
3.
Environ Technol ; 35(9-12): 1418-26, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24701940

RESUMO

The ability of a laboratory-scale dielectric barrier discharge (DBD) nonthermal plasma reactor at atmospheric pressure was assessed for the removal of bisphenol A (1 mg L(-1)) and tributyltin (10 mg L(-1)) from aqueous solutions. The elimination of both the compounds followed an exponential decay equation, and a first-order degradation kinetics was proposed for them (k = 0.662 min(-1) for bisphenol A and k = 0.800 min(-1) for tributyltin), reaching in both cases about 96% removal after 5-min treatment. Accordingly, plasma DBD reactors could be used as alternative advanced oxidation technologies for the removal of some persistent and toxic pollutants from water and wastewater, although further research should be performed to evaluate the effluent toxicity.


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Fenóis/isolamento & purificação , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/instrumentação , Cinética
4.
Yakugaku Zasshi ; 130(2): 223-35, 2010 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-20118647

RESUMO

The use of tributyltin (TBT) and triphenyltin (TPT) in some household products are prohibited by "Act on the Control of Household Products Containing Harmful Substances" in Japan. In this study, methods for determination of TBT and TPT in water soluble paints and adhesives were developed by GC-MS. These compounds in paints and adhesives, which were mainly composed of vinyl acetate, urethane and acryl resins, and chloroprene rubber, were firstly extracted with HCl-acetone, and then extracted with hexane. On the other hand, the adhesive composed of natural rubber was firstly dispersed in water before acidification. The organotins were extracted with hexane from this solution and then these compounds were extracted with acetonitrile from hexane extract. These extracts were purified by a florisil cartridge column after ethyl-derivation with sodium tetraethylborate, and analyzed by GC-MS. The quantifications using deuterated compound of both organotins as surrogate standard were conducted, and good results were obtained. The recoveries were 81 to 118% and the coefficients of variation were 0.83 to 4.3% (TBT and TPT added; 5 microg/g). The method quantification limits were 0.0090 to 0.025 microg/g, which were lower than those of an official method. These methods were applied to monobutyltin (MBT), dibutyltin (DBT), monophenyltin (MPT), and diphenyltin (DPT). DBT and DPT in paints and adhesives were quantified, except for DPT in natural rubber. These methods were applied to commercial products. DBT was detected at low concentrations (t.r.-0.19 microg/g) in some paint samples, while TBT and TPT were not detected in all samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos de Estanho/análise , Pintura/análise , Água , Compostos Orgânicos de Estanho/isolamento & purificação , Solubilidade , Compostos de Trialquitina/análise , Compostos de Trialquitina/isolamento & purificação
5.
Int J Biol Macromol ; 108: 1219-1226, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29126943

RESUMO

Tributyltin (TBT) used in a variety of industrial processes, subsequent discharge into the environment, its fate, toxicity and human exposure are topics of current concern. TBT degradation by alkaliphilic bacteria may be a key factor in the remediation of TBT in high pH contaminated sites. In this study, Stenotrophomonas chelatiphaga HS2 were isolated and identified from TBT contaminated site in Mediterranean Sea. S. chelatiphaga HS2 has vigor capability to transform TBT into dibutyltin and monobutyltin (DBT and MBT) at pH 9 and 7% NaCl (w/v). A gene was amplified and characterized from strain HS2 as SugE protein belongs to SMR protein family, a reverse transcription polymerase chain reaction analysis confirmed that SugE protein involved in the TBT degradation by HS2 strain. TBT bioremediation was investigated in stimulated TBT contaminated sediment samples (pH 9) using S chelatiphaga HS2 in association with E. coli BL21 (DE3)-pET28a(+)-sugE instead of S chelatiphaga HS2 alone reduced significantly the TBT half-life from 12d to 5d, although no TBT degradation appeared using E. coli BL21 (DE3)-pET28a(+)-sugE alone. This finding indicated that SugE gene increased the rate and degraded amount of TBT and is necessary in enhancing TBT bioremediation.


Assuntos
Proteínas de Bactérias/metabolismo , Stenotrophomonas/metabolismo , Compostos de Trialquitina/isolamento & purificação , Compostos de Trialquitina/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Biodegradação Ambiental , Sedimentos Geológicos/microbiologia , Concentração de Íons de Hidrogênio , Compostos Orgânicos de Estanho/metabolismo , Stenotrophomonas/fisiologia , Compostos de Trialquitina/farmacologia , Poluentes Químicos da Água/farmacologia
6.
Chemosphere ; 179: 75-83, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28363095

RESUMO

Organotin compounds have been widely used in recent decades, however, the residential tributyltin (TBT) in environment has potential harmful effects on human health due to the disruption of endocrine system even at trace level. Herein, this work reports on an effective electro-field-assisted-photocatalytic technique for removal of TBT by applying an electric field to photocatalysis of as-prepared hierarchical TiO2 microspheres. The synthesis of catalytic materials is based on a self-assembly process induced by microwave-assisted solvothermal reaction. Hierarchical TiO2 microspheres consisting of nanowires can be obtained in short time with this facile method and possess high surface area and superior optical properties. As the catalyst, it was found that the reaction rate constant of electro-field-assisted-photocatalytic removal (0.0488 min-1) of TBT exhibited almost a 9 fold improvement as compared to that of photocatalysis (0.0052 min-1). The proposed mechanism of electro-field-assisted-photocatalytic removal of TBT was verified by using 117Sn-enriched TBT spike solution as an isotopic tracer. In addition, varying impacts from some key reaction conditions, such as voltage of potential, pH value and the presence of Cr and formaldehyde were also discussed. The overall satisfactory TBT removal performance of the proposed electro-field-assisted-photocatalysis procedure with hierarchical TiO2 microspheres, which was validated using actual tannery wastewater samples from three different kinds of tanning procedures. These attributes suggest that this electro-field-assisted-photocatalysis may have broad applications for the treatment of tannery wastewater.


Assuntos
Microesferas , Titânio/química , Compostos de Trialquitina/isolamento & purificação , Águas Residuárias/química , Purificação da Água/métodos , Catálise , Técnicas Eletroquímicas/métodos , Micro-Ondas , Curtume
7.
J Chromatogr A ; 1459: 112-119, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27388657

RESUMO

Monitoring of water quality is important to control water pollution. Contamination of the aquatic system has a large effect on human health and the environment. Under the European Water Framework Directive (WFD) 2000/60/EC and the related directive on environmental quality standards (EQS) in the field of water policy 2008/105/EC, the need for sensitive reference methods was highlighted. Since tributyltin (TBT) is one of the WFD listed priority substances a method was developed which is capable to qualify and quantify the pollutant at the required low WFD EQS of 0.2ngL(-1) in whole water bodies, i.e. in non-filtered water samples with dissolved organic carbon and suspended particulate matter. Therefore special attention was paid on the interaction of TBT with the suspended particulate matter and humic substances to obtain a complete representation of the pollution in surface waters. Different water samples were investigated varying the content of organic dissolved and suspended matter. Quantification was performed using species-specific isotope dilution (SSID) and gas chromatography with inductively coupled plasma mass spectrometry (GC-ICP-MS). Different sample treatment strategies were evaluated and compared. The process of internal standard addition was investigated and optimized, hence the equilibrium between internal standards and matrix is of primary importance to perform accurate SSID. Samples spiked at EQS level were analyzed with a recovery between 95 and 105 %. Additionally real surface water samples were investigated and the TBT concentration for the whole water body was determined and compared with conventional routine analysis method.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Compostos de Trialquitina/análise , Água/análise , Filtração , Água Doce/análise , Humanos , Substâncias Húmicas/análise , Técnicas de Diluição do Indicador , Material Particulado/análise , Microextração em Fase Sólida , Compostos de Trialquitina/isolamento & purificação , Qualidade da Água
8.
J Chromatogr A ; 1048(1): 81-8, 2004 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-15453422

RESUMO

This paper describes the liquid-phase microextraction (LPME) of tributyltin (TBT) and triphenyltin coupled with gas chromatography-tandem mass spectrometry. The 4-fluorophenylation and ethylation reactions were used for the derivatization of the organotins. For the two derivatizations, the LPME parameters such as organic solvent, stirring rate, temperature, extraction time and the other additional conditions were examined. Using pure water, the calibration curves, method detection limits (MDLs) and reproducibilities (RSDs) of the two derivatizations were compared under the respective optimized procedures. The 4-fluorophenyl derivatization, which showed a lower MDL (0.36 ng/l) and better reproducibility (RSD = 11% at 10 ng/l) for TBT, was applied to the analysis of seawater. The TBT was detected in the range from 1.1 to 2.0 ng/l in the seawater samples collected in Osaka Bay.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos de Estanho/isolamento & purificação , Compostos de Trialquitina/isolamento & purificação , Soluções Tampão , Indicadores e Reagentes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Chromatogr A ; 655(2): 340-5, 1993 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-8111474

RESUMO

Supercritical fluid extraction is used to extract tributyltin and triphenyltin from biological samples. The extraction conditions with carbon dioxide as supercritical fluid (methanol modifier used) are optimized for the organotins from fish tissue certified reference material. The total extraction time is found to be approximately 15 min. The recovery studies at the optimal conditions shows a recovery of 44% for tributyltin and 23% for triphenyltin. The reproducibilities for both the compounds extracted are within 2% R.S.D. The optimum conditions obtained are also used to extract tributyltin and triphenyltin from tuna fish obtained from a local grocery store.


Assuntos
Peixes/metabolismo , Carne/análise , Compostos Orgânicos de Estanho/isolamento & purificação , Atum/metabolismo , Animais , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Compostos Orgânicos de Estanho/química , Compostos de Trialquitina/isolamento & purificação
10.
Mar Pollut Bull ; 45(1-12): 362-71, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12398407

RESUMO

The removal of tributyltin (TBT) from artificial wastewater by dead and live cells of four microalgal species, Chlorella miniata, C. sorokiniana, Scenedesmus dimorphus and S. platydiscus was investigated. Dead cells were generally more efficient in removing TBT during three days exposure. More than 90% and 85% TBT were removed by dead cells of Scenedesmus and Chlorella, respectively. Although the removal percentages of live microalgae were smaller, TBT was continuously absorbed and degraded, and TBT removal percentages similar to respective dead cells were achieved at the end of 14 days treatment. Degradation products, DBT and MBT, were recorded mainly inside the cells, and intracellular MBT concentrations were significantly higher than DBT. In terms of TBT removal, Scenedesmus cells were more effective than Chlorella, probably due to larger cell sizes and biomass. However, TBT specific uptake and degradation by Chlorella was higher than in Scenedesmus. The highest specific TBT uptake values, as well as the highest degradation, were recorded in C. miniata, a Hong Kong isolate.


Assuntos
Clorófitas/fisiologia , Compostos de Trialquitina/farmacocinética , Poluentes Químicos da Água/farmacocinética , Adsorção , Biomassa , Distribuição Tecidual , Compostos de Trialquitina/isolamento & purificação , Compostos de Trialquitina/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo
11.
Environ Sci Pollut Res Int ; 11(4): 267-72, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15341317

RESUMO

BACKGROUND: Organotins have been used world-wide as antifoulants in ship paints. Repeatedly, severe effects on aquatic species have resulted. The use of organotins for this purpose was ruled out, and dumping of contaminated harbor sludge into the sea was prohibited. Land-based dumping is seen as an alternative. OBJECTIVE: This study investigates sorption, uptake and translocation of tributyltin (TBT) to willow trees in order to evaluate phytoremediation as treatment option. The study considers the influence of pH on the plant uptake of organotins. EXPERIMENTAL SET-UP: Chemicals investigated were the weak base tributyltin chloride (TBTCl) and the neutral tributyltin hydride (TBTH). Organotins were extracted from solution and plant material with toluene, and analyzed as tin by AAS with graphite oven. The pH in solution varied from pH 4 to pH 7. The sorption to living and dead roots, stems and leaves was measured in shaking experiments. The uptake into intact trees was measured at nominal levels of 1 and 10 mg TBT/l for TBTH and TBTCl at low and high pH. RESULTS: The sorption to roots and leaves dropped for dead tissue, but did not vary much with pH. The sorption to stems increased for dead stems and with pH. The solubility of TBTCl in water was below 10 mg/l and lowest at pH 4. Concentrations of TBTCl and TBTH in solutions with trees dropped rapidly to low values. Highest TBT contents in trees were found in roots and lower stems. The concentrations followed the concentrations in solution. The pH had only a small effect on the plant uptake of TBTCl, and no effect on the uptake of TBTH. No effective translocation to higher stems or leaves was found. DISCUSSION: An ion trap mechanism that accumulates the weak base TBTCl in the xylem sap of plants and leads to upward translocation could not be detected. Neither TBTCl at low or high pH, nor the neutral lipophilic chemical TBTH, were translocated effectively to leaves. The TBT+ cation sorbed strongly to plant tissue. The exact mechanism for the strong sorption of the cation is unknown, but similar effects have been observed for algae, liposomes and isolated biomembranes. CONCLUSIONS: Both the uptake of the neutral TBTH and the uptake of the neutral molecule form of TBTCl into willows was as is to be expected from theory. The cation TBT+ showed an unexpected behavior which has been observed before. No ion trap occurs, and the phytoextraction of TBT is not feasible. OUTLOOK: Planting trees, or other appropriate vegetation, could have a beneficial remediation effect by aeration of the TBT-contaminated soil or sludge. In a follow-up paper, the toxicity of TBT to willow trees will be described.


Assuntos
Salix/química , Poluentes do Solo/farmacocinética , Compostos de Trialquitina/farmacocinética , Poluentes Químicos da Água/farmacocinética , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Raízes de Plantas/fisiologia , Poluentes do Solo/isolamento & purificação , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
12.
Environ Technol ; 25(6): 733-40, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15369293

RESUMO

Discharge consents for tributyltin (TBT) from wastewater treatment works in the UK are set by the Environment Agency. These values are normally derived from the Environmental Quality Standards for concentrations of TBT in the receiving water, based on the volume of effluent discharged and subsequent dilution within the environment. In this study, a sampling program was designed to monitor concentrations of TBT (and other organotins) in the influent and effluent at each stage of treatment. Sampling was undertaken at 3 hourly intervals, over 24 hours, at 8 locations throughout the works for five days. Organotin concentrations were determined using capillary gas chromatography with flame photometric detection. The results demonstrated that TBT was consistently present in the influent at concentrations of approximately 0.1 microg l(-1). However, a "pulse" of TBT and monobutyltin (MBT) was observed on the third day when the concentration of TBT and MBT in the influent increased to 14 microg l(-1). This "pulse" of TBT and MBT was also observed as the wastewater passed through the unit treatment processes. Concentrations of both compounds were much reduced in the final effluent (TBT 2.5 microg l(-1) and MBT 6.9 microg l(-1)). Over the entire period, the average removal of TBT during primary treatment was 81%, and during secondary biological treatment was 71%. The overall removal efficiency of the plant, taking into account the recycling of returned liquors was 86% between influent and effluent for TBT. Removal efficiency of TBT was correlated to that of suspended solids, and it was demonstrated that on days when suspended solids removal was low, TBT removal was also reduced. The mass flow of organotins through the plant indicated that the majority of TBT was concentrated into the sewage sludge. Concentrations of TBT in sludge at the plant were approximately 18 microg kg(-1) (dry weight).


Assuntos
Compostos Orgânicos de Estanho/isolamento & purificação , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
13.
Talanta ; 126: 8-11, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24881528

RESUMO

Stir bar sorptive extraction with in-situ derivatization using sodium tetrahydridoborate (NaBH4) followed by liquid desorption and large volume injection-gas chromatography-mass spectrometry detection under the selected ion monitoring mode (SBSE(NaBH4)in-situ-LD/LVI-GC-MS(SIM)) was successfully developed for the determination of tributyltin (TBT) in environmental water matrices. NaBH4 proved to be an effective and easy in-situ speciation agent for TBT in aqueous media, allowing the formation of adducts with enough stability and suitable polarity for SBSE analysis. Assays performed on water samples spiked at the 10.0µg/L, yielded convenient recoveries (68.2±3.0%), showed good accuracy, suitable precision (RSD<9.0%), low detection limits (23ng/L) and excellent linear dynamic range (r(2)=0.9999) from 0.1 to 170.0µg/L, under optimized experimental conditions. By using the standard addition method, the application of the present methodology to real surface water samples allowed very good performance at the trace level. The proposed methodology proved to be a feasible alternative for routine quality control analysis, easy to implement, reliable and sensitive to monitor TBT in environmental water matrices.


Assuntos
Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Boroidretos/química , Estudos de Viabilidade , Análise de Injeção de Fluxo/métodos , Reprodutibilidade dos Testes , Compostos de Trialquitina/química , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
14.
Talanta ; 116: 559-62, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24148445

RESUMO

A novel approach has been developed for the separation of organotin species with capillary electrophoresis hyphenated to time-of-flight mass spectrometry. It has been applied to the development of a method for the determination and speciation of organotin compounds namely, dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT) and triphenyltin (TPT) in water samples. Experiments were made with a special laboratory constructed CE instrument. A non-aqueous buffer system compatible with TOF-MS has been developed using ammonium acetate-acetic acid (50 mM and 1 M) in acetonitrile: methanol (80:20). The total analysis time is less than 3 min for these compounds under the conditions developed. The method has been applied successfully to the determination of these compounds in river water samples. Detection limits of the CE-TOF-MS method were between 1 and 8×10(-7) M, and between 2 and 11×10(-9) M (0.46 to 3.2 µg L(-1)) when used in conjunction with solid phase extraction. The short analysis time as well as good sensitivity and selectivity make it a useful approach for the fast screening of organotin compounds.


Assuntos
Água Doce/química , Compostos Orgânicos de Estanho/isolamento & purificação , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Eletroforese Capilar/métodos , Humanos , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Fatores de Tempo
15.
Artigo em Inglês | MEDLINE | ID: mdl-23416291

RESUMO

Analysis of tributyltin chloride (TBT) in environmental samples, such as seawater, is important in order to evaluate the TBT contamination and accumulation in the trophic chain. The environmental impact of organotin compounds has been a particular focus of analytical studies. The present study reports the use of molecular imprinting technology coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to determine trace amounts of TBT in seawater and seafood (mussel tissue samples). The imprinted polymer was synthesized by a non-covalent free-radical approach using acrylamide (AM) as a monomer and TBT as a template molecule in acetonitrile solvent (polymerization media). The imprinted polymer synthesized by this approach exhibited good adsorptive capacity and allowed specific retention of TBT. Recoveries of TBT in seawater samples spiked with different TBT concentrations ranged from 67.2% to 81.1% with peak area precision (RSD)<3.7%, and recoveries of TBT in mussel tissue samples ranged from 75.0% to 94.2% with RSD<4.8%.


Assuntos
Bivalves/química , Monitoramento Ambiental/métodos , Alimentos Marinhos/análise , Água do Mar/análise , Compostos de Trialquitina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Animais , Cromatografia Líquida/métodos , Limite de Detecção , Impressão Molecular/métodos , Polímeros/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
16.
J Chromatogr A ; 1261: 151-7, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-22889600

RESUMO

According to recent directives of the European Union (EU), limits of quantification (LOQ) for the determination of tributyltin (TBT) in surface waters should be ca. 60 pg/L (ppq). This put very stringent requirements on analytical methodologies; definitely when they have to be applied in a routine environment. Stir bar sorptive extraction (SBSE), followed by thermal desorption (TD) and capillary gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) can provide accurate and precise data at the 2 ng/L level (ppt). For lower concentrations, matrix and reagent interferences together with contamination may provide too high TBT values. A two-dimensional heart-cut GC method was developed to fractionate TBT from interferences. The GC-GC-MS/MS method shows excellent linearity in the range 50 pg/L-4 ng/L, good repeatability (RSD<20% at 200 pg/L), and a limit of detection of 11 pg/L. The method performance is demonstrated with representative samples i.e. harbor water and waste water samples.


Assuntos
Monitoramento Ambiental/métodos , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Fracionamento Químico/métodos , Água Potável/química , Monitoramento Ambiental/normas , União Europeia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Oceanos e Mares , Reprodutibilidade dos Testes , Compostos de Trialquitina/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação
17.
Talanta ; 80(5): 1913-8, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20152432

RESUMO

A microwave-assisted extraction used to extract trace triorganotin from aquatic organisms and a sensitive analytical method for the determination of ultratrace triorganotin (namely trimethyltin, triethyltin, tripropyltin and tributyltin) with capillary electrophoresis-inductively coupled plasma mass spectrometry were firstly described in this study. The extraction method is simple, effective and can be used to extract trace triorganotin in aquatic organisms within several min. The analytical method has a much lower detection limit of 0.2-0.7 ng Sn/mL for triorganotin compounds, and can be used to determine trace triorganotin in aquatic organisms directly without any derivatization and preconcentration. Using above methods, we have successfully determined trimethyltin, triethyltin, tripropyltin and tributyltin in dried Mya arenaria Linnaeus and Corbicula fluminea within 17 min with a recovery of 93-104% and a RSD (relative standard deviation, n=6) of 2-5%. Our results showed that dried M. arenaria Linnaeus contained an extremely high tributyltin of 5.1 microg Sn/g dried weight, indicating that it may be a good biomarker for the organotin pollution in ocean.


Assuntos
Corbicula/química , Eletroforese Capilar/métodos , Espectrometria de Massas/métodos , Mya/química , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Animais , Eletroforese Capilar/economia , Limite de Detecção , Espectrometria de Massas/economia , Reprodutibilidade dos Testes , Compostos de Trialquitina/isolamento & purificação
18.
Anal Bioanal Chem ; 383(2): 153-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16136305

RESUMO

An accurate and sensitive multi-species species-specific isotope dilution GC-ICP-MS method was developed for the simultaneous determination of trimethyllead (Me3Pb+), monomethylmercury (MeHg+) and the three butyltin species Bu3Sn+, Bu2Sn2+, and BuSn3+ in biological samples. The method was validated by three biological reference materials (CRM 477, mussel tissue certified for butyltins; CRM 463, tuna fish certified for MeHg+; DORM 2, dogfish muscle certified for MeHg+). Under certain conditions, and with minor modifications of the sample pretreatment procedure, this method could also be transferred to environmental samples such as sediments, as demonstrated by analyzing sediment reference material BCR 646 (freshwater sediment, certified for butyltins). The detection limits of the multi-species GC-ICP-IDMS method for biological samples were 1.4 ng g(-1) for MeHg+, 0.06 ng g(-1) for Me3Pb+, 0.3 ng g(-1) for BuSn3+ and Bu3Sn+, and 1.2 ng g(-1) for Bu2Sn2+. Because of the high relevance of these heavy metal alkyl species to the quality assurance of seafood, the method was also applied to corresponding samples purchased from a supermarket. The methylated lead fraction in these samples, correlated to total lead, varied over a broad range (from 0.01% to 7.6%). On the other hand, the MeHg+ fraction was much higher, normally in the range of 80-100%. Considering that we may expect tighter legislative limitations on MeHg+ levels in seafood in the future, we found the highest methylmercury contents (up to 10.6 microg g(-1)) in two shark samples, an animal which is at the end of the marine food chain, whereas MeHg+ contents of less than 0.2 microg g(-1) were found in most other seafood samples; these results correlate with the idea that MeHg+ is usually of biological origin in the marine environment. The concentration of butyltins and the fraction of the total tin content that is from butyltins strongly depend on possible contamination, due to the exclusively anthropogenic character of these compounds. A broad variation in the butylated tin fraction (in the range of <0.3-49%) was therefore observed in different seafood samples. Corresponding isotope-labeled spike compounds (except for trimethyllead) are commercially available for all of these compounds, and since these can be used in the multi-species species-specific GC-ICP-IDMS method developed here, this technique shows great potential for routine analysis in the future.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Metilmercúrio/análise , Chumbo Tetraetílico/análogos & derivados , Compostos de Trialquitina/análise , Animais , Bivalves/química , Bivalves/metabolismo , Peixes/sangue , Compostos de Metilmercúrio/isolamento & purificação , Compostos de Metilmercúrio/normas , Técnica de Diluição de Radioisótopos , Sensibilidade e Especificidade , Especificidade da Espécie , Chumbo Tetraetílico/análise , Chumbo Tetraetílico/isolamento & purificação , Chumbo Tetraetílico/normas , Distribuição Tecidual , Compostos de Trialquitina/isolamento & purificação , Compostos de Trialquitina/normas
19.
Anal Chem ; 75(16): 4095-102, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-14632122

RESUMO

A rapid, accurate, sensitive, and simple method for simultaneous speciation analysis of mercury and tin in biological samples has been developed. Integrated simultaneous sample preparation for tin and mercury species includes open focused microwave extraction and derivatization via ethylation. Capillary gas chromatography-inductively plasma mass spectrometry (CGC-ICPMS) conditions and parameters affecting the analytical performance were carefully optimized both for species-specific isotope dilution analysis of MMHg and TBT and for conventional analysis of MBT and DBT201Hg-enriched monomethylmercury and 117Sn-enriched tributyltin were used for species-specific isotope dilution mass spectrometry (SIDMS) analysis. As important, accurate isotope dilution analysis requires equilibration between the spike and the analyte to achieve successful analytical procedures. Since the spike stabilization and solubilization are the most critical and time-consuming steps in isotope dilution analysis, different spiking procedures were tested. Simultaneous microwave-assisted spike stabilization and solubilization can be achieved within less than 5 min. This study originally introduces a method for the simultaneous speciation and isotope dilution of mercury and tin in biological tissues. The sample throughput of the procedure was drastically reduced by fastening sample preparation and GC separation steps. The accuracy of the method was tested by both external calibration analysis and species-specific isotope dilution analysis using the first biological reference material certified for multielemental speciation (oyster tissue, CRM 710, IRMM). The results obtained demonstrate that isotope dilution analysis is a powerful method allowing the simultaneous speciation of TBT and MMHg with high precision and excellent accuracy. Analytical problems related to low recovery during sample preparation are thus minimized by SIDMS. In addition, a rapid procedure allows us to establish a performant routine method using CGC-ICPMS technique.


Assuntos
Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Metilmercúrio/análise , Ostreidae/química , Compostos de Trialquitina/análise , Animais , Poluentes Ambientais/isolamento & purificação , Isótopos de Mercúrio , Compostos de Metilmercúrio/isolamento & purificação , Compostos de Metilmercúrio/normas , Micro-Ondas , Padrões de Referência , Radioisótopos de Estanho , Compostos de Trialquitina/isolamento & purificação , Compostos de Trialquitina/normas
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