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1.
Molecules ; 26(22)2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34833943

RESUMO

Every petroleum-processing plant produces sewage sludge containing several types of polycyclic aromatic hydrocarbons (PAHs). The degradation of PAHs via physical, biological, and chemical methods is not yet efficient. Among biological methods, the use of marine sponge symbiont bacteria is considered an alternative and promising approach in the degradation of and reduction in PAHs. This study aimed to explore the potential performance of a consortium of sponge symbiont bacteria in degrading anthracene and pyrene. Three bacterial species (Bacillus pumilus strain GLB197, Pseudomonas stutzeri strain SLG510A3-8, and Acinetobacter calcoaceticus strain SLCDA 976) were mixed to form the consortium. The interaction between the bacterial consortium suspension and PAH components was measured at 5 day intervals for 25 days. The biodegradation performance of bacteria on PAH samples was determined on the basis of five biodegradation parameters. The analysis results showed a decrease in the concentration of anthracene (21.89%) and pyrene (7.71%), equivalent to a ratio of 3:1, followed by a decrease in the abundance of anthracene (60.30%) and pyrene (27.52%), equivalent to a ratio of 2:1. The level of pyrene degradation was lower than that of the anthracene due to fact that pyrene is more toxic and has a more stable molecular structure, which hinders its metabolism by bacterial cells. The products from the biodegradation of the two PAHs are alcohols, aldehydes, carboxylic acids, and a small proportion of aromatic hydrocarbon components.


Assuntos
Acinetobacter calcoaceticus/fisiologia , Antracenos/metabolismo , Bacillus pumilus/fisiologia , Poríferos/fisiologia , Pseudomonas stutzeri/fisiologia , Pirenos/metabolismo , Animais , Antracenos/isolamento & purificação , Biodegradação Ambiental , Microbiota , Pirenos/isolamento & purificação , Simbiose
2.
Mikrochim Acta ; 187(1): 78, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894420

RESUMO

A polyaniline composite doped with etched multi-walled carbon nanotubes and UiO-66-NH2 was prepared by electropolymerization. It was used as a sorbent to extract the polycyclic aromatic hydrocarbons (PAHs) phenanthrene, fluoranthene and pyrene. Its surface morphology, crystal structure and capability of adsorbing PAHs were characterized by scanning electron microscopy, X-ray photoelectron spectrometry, Fourier transform infrared spectrometry and zeta potentiometry. The π stacking and anion-π interactions are shown to play dominant roles in the sorption mechanism. Coupled with high performance liquid chromatography, the composite-modified fiber was applied to detect PAHs in lake water samples by direct immersion extraction. The method excels by (a) wide linear range (0.05-20 ng mL-1), (b) low limits of detection (10 pg mL-1), (c) satisfactory recovery from spiked samples (84.7-113.8%), and (d) good reproducibility (relative standard deviations of <6.5%). The method is superior in terms of costs and reproducibility compared to some pretreatment methods with mass spectrometric detection. Graphical abstractSchematic representation for interaction between PANI-etched MWCNT/UiO-66-NH2 and polycyclic aromatic hydrocarbons (phenanthrene, fluoranthene, pyrene).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Nanocompostos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Poluentes da Água/isolamento & purificação , Adsorção , Compostos de Anilina/química , Cromatografia Líquida de Alta Pressão/normas , Fluorenos/isolamento & purificação , Lagos/química , Limite de Detecção , Estruturas Metalorgânicas/química , Nanotubos de Carbono/química , Fenantrenos/isolamento & purificação , Pirenos/isolamento & purificação , Reprodutibilidade dos Testes
3.
Chemosphere ; 242: 125160, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31669988

RESUMO

Surfactant enhanced remediation (SER) is an effective approach for decontaminating the PAH polluted soils. Solubilization and Cosolubilization of Phenanthrene (Ph), Pyrene (Py) and Perylene (Pe) as single, binary and ternary mixtures have been studied employing cationic (CTAB), anionic (SDS), non-ionic surfactant (Brij 30) and block copolymer (P123) micelles. In the single solute solubilization studies, solubility of Pe follows the order Brij 30 > CTAB > SDS whereas Ph or Py followed the order of CTAB > Brij 30 > SDS. In the cosolubilization studies, an increase, decrease or no change in the mutual solubility of PAHs was observed. Synergism in solubilization was observed most in P123 in both binary and ternary PAH mixture where more PAHs could get solubilized in the dense micellar shell region, thereby enhancing the micellar core volume leading to enhanced solubilization of PAHs. The solubilizates as pairs (Ph-Pe and Py-Pe) were further tested for any possible energy transfer in presence of surfactant based restricted host environments using spectrofluorometry and spectrophotometry. Based on the solubilization and cosolubilization an efficient non-radiative energy transfer (FRET) was observed between Ph/Py (donor) and Pe (acceptor) in the non-ionic surfactant system as well as in CTAB-Brij 58 mixed system. The results of this work may improve the effective utilization of surfactants in their correct evaluation for the removal of PAHs from contaminated soils or aquifers treated with SER technology.


Assuntos
Recuperação e Remediação Ambiental/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Micelas , Hidrocarbonetos Policíclicos Aromáticos/química , Tensoativos/química , Fenantrenos/química , Fenantrenos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Pirenos/química , Pirenos/isolamento & purificação , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Solubilidade , Água
4.
J Chromatogr A ; 1603: 160-164, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31272732

RESUMO

An environmentally benign and cost-effective method was designed for isolating and purifying condensed arenes from acetone-extractable portion (AEP) of a high-temperature coal tar through a high pressure preparative chromatograph (HPPC) with different packings, including silica gel, octadecyl silane, octyl bonded silica gel, and diol bonded silica gel. In total, 196 compounds were detected with a gas chromatograph/mass spectrometer from AEP and its eluates. From the eluates, naphthalene, anthracene, phenanthrene, fluoranthene, and pyrene were successfully isolated and purified, and their structures were confirmed by their 1H and 13C nuclear magnetic resonance spectra in addition to their mass spectra. Extraction-HPPC device and solvent recovery process were designed and developed, which can potentially be applied to industrial production because the process is easy-to-operate and ecofriendliness. In addition, the solvents used can be easily recovered and reused, and neither waste water nor other pollutions are emitted.


Assuntos
Alcatrão/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura Alta , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Pressão , Antracenos/isolamento & purificação , Fluorenos/isolamento & purificação , Naftalenos/isolamento & purificação , Fenantrenos/isolamento & purificação , Pirenos/isolamento & purificação
5.
Lab Chip ; 19(13): 2233-2240, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31161167

RESUMO

Ion concentration polarization (ICP) has been broadly applied to accomplish electrokinetic focusing of charged species. However, ICP-based extraction and enrichment of uncharged (neutral) compounds, important for pharmaceutical, biological, and environmental applications, has not yet been reported. Here, we report the ICP-based continuous extraction of two neutral compounds from aqueous solution, by their partition into an ionic micellar phase. Our initial results show that the efficiency of the extraction increases with the concentration of the surfactant comprising the micellar phase, reaching 98 ± 2%, and drops precipitously when the concentration of the target compound exceeds the capacity of the micelles. As a key feature relevant to the practical application of this method, we show that focusing occurs even an order of magnitude below the critical micelle concentration through the local enrichment and assembly of surfactants into micelles, thus minimizing their consumption. To underscore the relevance of this approach to water purification, this method is applied to the extraction of pyrene, a model for polyaromatic hydrocarbons. This approach provides access to a broad range of strategies for selective separation that have been developed in micellar electrokinetic chromatography.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Técnicas Analíticas Microfluídicas , Pirenos/isolamento & purificação , Tensoativos/química , Íons/química , Micelas , Técnicas Analíticas Microfluídicas/instrumentação , Pirenos/química , Soluções , Água/química
6.
Anal Bioanal Chem ; 411(15): 3281-3290, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989270

RESUMO

Quantification of ultra-trace analytes in complex biological samples using micro-solid-phase extraction followed by direct detection with internal extractive electrospray ionization mass spectrometry (µSPE-iEESI-MS) was demonstrated. 1-Hydroxypyrene (1-OHP) and papaverine at attomole levels in human raw urine samples were analyzed under negative and positive ion detection mode, respectively. The µSPE was simply prepared by packing a disposable syringe filter with octadecyl carbon chain (C18)-bonded micro silica particles, which were then treated as the "bulk sample" after the analytes were efficiently enriched by the C18 particles. Under the optimized experimental conditions, the analytes were readily eluted by isopropanol/water (80/20, V/V) at a high voltage of ± 4.0 kV, producing analyte ions under ambient conditions. The limit of detection (LOD) was 0.02 pg/L (9.2 amol) for 1-hydroxypyrene and 0.02 pg/L (5.9 amol) for papaverine. The acceptable linearity (R2 > 0.99), signal stability (RSD ≤ 10.7%), spike recoveries (91-95%), and comparable results for real urine samples were also achieved, opening up possibilities for quantitative analysis of trace compounds (at attomole levels) in complex bio-samples. Graphical abstract.


Assuntos
Papaverina/urina , Pirenos/urina , Microextração em Fase Sólida/instrumentação , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Vasodilatadores/urina , Adsorção , Biomarcadores/urina , Desenho de Equipamento , Humanos , Limite de Detecção , Papaverina/isolamento & purificação , Pirenos/isolamento & purificação , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos , Vasodilatadores/isolamento & purificação
7.
Mikrochim Acta ; 186(5): 300, 2019 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-31025201

RESUMO

The exploration of monohydroxy polycyclic aromatic hydrocarbons and 8-hydroxy-2'-deoxyguanosine (8-OHdG) produced by oxidative stress and DNA damage is a powerful and non-invasive tool to study the health risk of exposure to polycyclic aromatic hydrocarbons (PAHs). A nanocomposite prepared from graphene oxide, poly(3,4-ethylenedioxythiophene) and polypyrrole was electrodeposited on the internal surface of a stainless-steel tube for online in-tube solid phase microextraction (IT-SPME) of 8-OHdG, 3-hydroxyphenanthrene and 1-hydroxypyrene from urine. The coating possesses excellent chemical and mechanical stability, high extraction efficiency, good resistance to matrix interference, and a long lifespan. An online IT-SPME-high performance liquid chromatography-mass spectrometry method was developed for the determination of these three metabolite biomarkers in human urine. Figures of merit include (a) enrichment factors of 30-48; (b) low limits of detection (4-41 pg·mL-1 at S/N = 3); (c) wide linear ranges (0.05-50 ng·mL-1); (d) good recoveries from spiked samples (71.6-109.5%); and (e) acceptable repeatability (2.3-14.6%). The method offers the advantages of low cost, simplicity, sensitivity, rapidity and automation. Graphical abstract Schematic illustration of online in-tube solid phase microextraction using graphene oxide/poly(3,4-ethylenedioxythiophene)/polypyrrole composites as adsorbent in a stainless-steel (SS) tube for the enrichment and simultaneous determination of 8-hydroxy-2'-deoxyguanosine, 3-hydroxyphenanthrene and 1-hydroxypyrene prior to HPLC-MS analysis.


Assuntos
8-Hidroxi-2'-Desoxiguanosina/urina , Compostos Bicíclicos Heterocíclicos com Pontes/química , Grafite/química , Fenantrenos/urina , Polímeros/química , Pirenos/urina , Pirróis/química , Urinálise/métodos , 8-Hidroxi-2'-Desoxiguanosina/química , 8-Hidroxi-2'-Desoxiguanosina/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas , Nanocompostos/química , Fenantrenos/química , Fenantrenos/isolamento & purificação , Pirenos/química , Pirenos/isolamento & purificação , Microextração em Fase Sólida , Fatores de Tempo , Urinálise/instrumentação
8.
J Mol Recognit ; 32(5): e2771, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30515937

RESUMO

Tuning of ligand structures through controlled variation of ring number in fused-ring aromatic moiety appended to antipyrine allows detection of 7.8 × 10-12  M pyrene via aggregation-induced emission (AIE) associated with 101-fold fluorescence enhancement. In one case, antipyrine unit is replaced by pyridine to derive bis-methylanthracenyl picolyl amine. The structures of four molecules have been confirmed by single crystal X-ray diffraction analysis. Among them, pyrene-antipyrine conjugate (L) undergoes pyrene triggered inhibition of photo-induced electron transfer (PET) leading to water-assisted AIE.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Pirenos/análise , Pirenos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Transporte de Elétrons , Ligantes , Modelos Moleculares , Estrutura Molecular , Pirenos/isolamento & purificação , Extração em Fase Sólida/métodos , Espectrometria de Fluorescência , Poluentes Químicos da Água/isolamento & purificação
9.
J Chromatogr A ; 1566: 44-50, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29937119

RESUMO

8-Aminopyrene-1,3,6-trisulfonate (APTS) is one of the most frequently used reagent in capillary electrophoresis. Three sulfonate groups in APTS generate fast electrophoretic mobilities of derivatized glycans, therefore very suitable for CE-LIF applications. However, these groups also make separation with partition chromatography difficult. A novel column for hydrophilic interaction liquid chromatography (HILIC) with an anionic tetrazole functionalized polymer-based silica was examined for the separation of APTS-labeled glycans derived from specific glycoproteins. This separation mode has enhanced capability for the size resolution of neutral and acidic oligosaccharides. In addition, specific glycan isomers, which are usually difficult to separate with HILIC methods, were also separated. IgG-derived complex-type glycans that have an isomeric pair of monogalactosylated glycans, as well as differences in the number of galactose residues, are separable using this mode. We also utilized this column for the fractionation of APTS-labeled glycans from porcine thyroglobulin and examined their migration times with CE by co-migration with a mixture of glycoprotein glycans. Combinational modes of HILIC and anionic repulsion show promise for the separation and preparation of glycoprotein-derived glycans labeled with APTS.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Polissacarídeos/isolamento & purificação , Pirenos/isolamento & purificação , Animais , Técnicas de Química Analítica/instrumentação , Glicoproteínas/química , Interações Hidrofóbicas e Hidrofílicas , Oligossacarídeos/química , Polissacarídeos/química , Suínos , Tetrazóis/química
10.
J Hazard Mater ; 336: 110-118, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28494298

RESUMO

The soil microbial fuel cells (SMFCs) were constructed to remediate soils contaminated by polycyclic aromatic hydrocarbons (PAHs). With a maximum power density of 12.1mWm-2 and an internal resistance of 470Ω, a closed SMFC showed electricity generation comparable to that by an open SMFC after 175days of operation and meanwhile increased the removal rates of anthracene, phenanthrene, and pyrene to 54.2±2.7%, 42.6±1.9% and 27.0±2.1% from 20.8±1.1%, 17.3±1.2% and 11.7±0.9%, respectively, by the open SMFC. Both the electricity generation and the removal of PAHs increased with the decreased electrode interval. When the electrode interval ranged between 4cm and 10cm, the more closely the electrodes were positioned, the more efficient the electricity generation and removal of PAHs became. Dominated by the genus of Geobacter, the SMFC was enriched in electrogenic bacteria at the anode surface, and the growth of certain microbes other than electrogenic bacteria in the soil was improved by electrical stimulation. This finding reveals the critical mechanism underlying electricity generation and improved the removal of PAHs.


Assuntos
Antracenos/isolamento & purificação , Fontes de Energia Bioelétrica , Eletrodos , Geobacter/metabolismo , Fenantrenos/isolamento & purificação , Pirenos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Biodegradação Ambiental , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Geobacter/genética , RNA Ribossômico 16S/genética
11.
Methods Mol Biol ; 1588: 223-236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28417373

RESUMO

Purified glycan standards are required for glycan arrays, characterizing substrate specificities of glycan-active enzymes, and to serve as retention-time or mobility standards for various separation techniques. This chapter describes a method for the rapid separation, and subsequent desalting, of glycans labeled with the highly fluorescent fluorophore 8-aminopyrene 1,3,6-trisulfonate (APTS). By using fluorophore-assisted carbohydrate electrophoresis (FACE) on polyacrylamide gels, which utilizes equipment readily available in most molecular biology laboratories, many APTS-labeled glycans can be simultaneously resolved. Excising specific gel bands containing the desired APTS-labeled glycans, followed by glycan elution from the gel and subsequent solid-phase extraction (SPE), yields single glycan species free of excess labeling reagents and buffer components. This chapter describes a FACE/SPE procedure ideal for preparing glycans for capillary electrophoresis (CE)-based enzyme assays, as well as for the purification of rare, commercially unavailable glycans from tissue culture samples.


Assuntos
Eletroforese Capilar/métodos , Ensaios Enzimáticos/métodos , Polissacarídeos/isolamento & purificação , Pirenos/química , Animais , Linhagem Celular , Eletroforese Capilar/economia , Ensaios Enzimáticos/economia , Polissacarídeos/química , Pirenos/isolamento & purificação
12.
Talanta ; 166: 375-382, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28213249

RESUMO

New analytical strategies tend to automation of sample pre-treatment and flow analysis techniques provided a number of enhanced analytical methods allowing high throughput. Flow techniques are usually faster, more robust and more flexible than their batch equivalents. In addition, flow methods use less sample and reagent amounts and reduce analytical costs and waste. A flow injection solid-phase extraction pre-concentration system using a molecularly imprinted polymer (MIP) packed micro-column was developed for the determination of 1-hydroxypyrene in human urine with fluorescence detection. The pre-concentration of 1-hydroxypyrene on the MIP was carried out based on the specific retention of analyte by on-line introducing the sample into the micro-column system. Methanol and dichloromethane mixture was used to elute the retained analyte for fluorometric analysis. Important influencing factors were studied in detail, in batch and in flow (MISPE procedure optimisation, sample and eluent volumes, flow rate, dimensions of MIP micro-column and amounts of packing material, etc). To the best of our knowledge, this is the first on-line flow injection molecularly imprinted solid phase extraction for the pre-concentration and determination of hydroxylate PAH metabolite in urine samples. The optimised method was successfully applied to the determination of 1-Hydroxypyrene in spiked urine samples, with recoveries in the range of 74-85% and RSD<4.6%. Under optimum experimental conditions, the linearity concentration range used was 10-400µgL-1, R2>0.996. We obtained limit of detection and quantification of 3.1µgL-1 and 10.5µgL-1, respectively.


Assuntos
Análise de Injeção de Fluxo , Impressão Molecular/métodos , Pirenos/isolamento & purificação , Pirenos/urina , Extração em Fase Sólida/métodos , Humanos , Recém-Nascido , Polímeros/síntese química , Solventes/química
13.
J Agric Food Chem ; 65(9): 1992-1999, 2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28215082

RESUMO

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are ubiquitous environmental pollutants attracting increasing attention because of their potent mutagenicity to humans. Previous studies of nitro-PAHs focused on investigating their formation mechanisms and detecting them in atmospheric environment; however, few studies have reported their occurrence in food samples, and regulations on nitro-PAHs are still lacking. We report in this study the development and application of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for determination of nitro-PAHs in rice and vegetable samples. Analysis of the collected samples by the validated method revealed 1-nitropyrene and 2-nitrofluorene were widespread food contaminants. A comparative study with benzo[a]pyrene, the commonly used marker for PAH exposure, showed that carcinogenic nitro-PAHs existed in rice and vegetables at similar concentrations. Dietary exposure risk, which was estimated based on the surveillance data, suggested 3.28-5.03 ng/kg/day of nitro-PAHs exposure for Hong Kong citizens from rice grains and vegetables.


Assuntos
Carcinógenos/isolamento & purificação , Poluentes Ambientais/isolamento & purificação , Fluorenos/isolamento & purificação , Oryza/química , Pirenos/isolamento & purificação , Verduras/química , Benzo(a)pireno/análise , Benzo(a)pireno/isolamento & purificação , Carcinógenos/análise , Cromatografia Líquida de Alta Pressão , Poluentes Ambientais/análise , Fluorenos/análise , Contaminação de Alimentos/análise , Hong Kong , Pirenos/análise , Sementes/química
14.
Cell Mol Biol (Noisy-le-grand) ; 62(3): 15-9, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-27064868

RESUMO

In this paper, an efficient method for determination of total pyrene concentration in the biological samples including plasma, liver, spleen, lung and kidney of Sprague-Dawley rats were investigated and established using steady-state fluorescence method. Equilibrium dialysis method was applied to determine plasma protein binding rate of pyrene. The results illustrated that the protein binding rate depends on the concentration of pyrene in plasma. Extraction of pyrene in plasma was studied by using biomedical nanopartical which was prepared from synthesized associating polymer poly(ethylene glycol) end-capped by hexadecane. The Critical Micelle Concentration (CMC) of the polymeric micelle in aqueous solution was determined to equal 0.0063 mg/mL using 1-pyrenemethanol as a fluorescent probe. The distribution of free pyrene and pyrene loaded nanoparticals in blood were determined. The results showed that over 95% of the free pyrene was distributed into the erythrocyte, and the pyrene-loaded nanoparticles were less distributed in to the erythrocyte than free pyrene, but it was higher than 60%. This study provides an efficient method to detect pyrene in different tissues as well as an extraction method at the molecular level, which might contribute to the development of modern molecular diagnosis and identification in vivo.


Assuntos
Corantes Fluorescentes/isolamento & purificação , Corantes Fluorescentes/farmacocinética , Nanopartículas/química , Polietilenoglicóis/química , Pirenos/isolamento & purificação , Pirenos/farmacocinética , Alcanos/química , Animais , Portadores de Fármacos/química , Eritrócitos/metabolismo , Corantes Fluorescentes/administração & dosagem , Rim/metabolismo , Fígado/metabolismo , Masculino , Micelas , Nanotecnologia , Pirenos/administração & dosagem , Pirenos/sangue , Ratos Sprague-Dawley , Espectrometria de Fluorescência , Baço/metabolismo
15.
Bull Environ Contam Toxicol ; 96(1): 113-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26573838

RESUMO

The adsorption behavior of pyrene on corncob was studied to provide a theoretical basis for the possible use of this material as an immobilized carrier for improving the bioremediation of PAH-contaminated soil. The results were as follows. Kinetic experiments showed that the adsorption processes obeyed a pseudo-second-order model. The intraparticle diffusion of Weber-Morris model fitting showed that the film and intraparticle diffusions were the key rate-limiting processes, and the adsorption process mainly consisted of three steps: boundary layer diffusion and two intra-particle diffusions. Experimental adsorption data for pyrene were successfully described by the adsorption-partition equilibrium model. The maximum adsorption capacity at 25°C was 214.8 µg g(-1). The adsorption contribution decreased significantly when the Ce/Sw (the equilibrium concentration/solubility in water) was higher than 1. Adsorption decreased with increased temperature. Based on the above results, the corncob particles could be helpful in the bioremediation of pyrene-contaminated soil.


Assuntos
Pirenos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Zea mays/química , Adsorção , Agricultura , Difusão , Cinética , Pirenos/química , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Solubilidade , Água , Poluentes Químicos da Água/química
16.
Biosens Bioelectron ; 78: 194-199, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26609944

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous homogeneous chemicals which are well known by carcinogens, mutagens and endocrine disorder. Here, an improved real-time immuno-PCR (RT-IPCR) was developed for detection of pyrene and its homologs in water samples. The PAHs in sample compete with pyrene-modified DNA to bind with monoclonal antibody (McAb) coated on PCR plate. The reporter DNA was exponentially amplified by real-time PCR instrument using Fast Start universal SYBR Green Master (ROX) kit. Only two reaction steps were needed to accomplish the detection. The assay had a good linear range from 5 pmol L(-1) to 5 nmol L(-1) with a detection limit of 3.5 pmol L(-1). For application assay, the average recoveries from tap water, lake water and mineral water were 98.4%, 98.2% and 99.7%, respectively which showed a good correlation (R(2)=0.9906) with those from GC-MS. The results indicated that the improved RT-IPCR seems to be a potential method for simple and ultrasensitive detection of pyrene and some homologues in environment water samples.


Assuntos
Técnicas Biossensoriais , Ensaio de Imunoadsorção Enzimática/métodos , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Pirenos/isolamento & purificação , Anticorpos Monoclonais/química , DNA/química , Água Doce/química , Cromatografia Gasosa-Espectrometria de Massas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Poluentes Químicos da Água/isolamento & purificação
17.
Talanta ; 143: 71-76, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26078130

RESUMO

In the last decades, the assessment of polycyclic aromatic hydrocarbons' exposure has generated great interest and 1-hydroxypyrene (1-OHP) has been commonly used as a biological indicator of exposure to PAHs in many studies in environmental and occupational health. In this research, a molecularly imprinted polymer (MIP) was synthesised by precipitation polymerisation using 1-OHP as template, methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as cross-linker, and acetonitrile as porogen. MIP was used as solid-phase extraction (SPE) material for sample pretreatment and isolation of 1-OHP and posterior detection in a reversed-phase HPLC-FLD. Various parameters including washing solvent, elution solvent and volume affecting the extraction efficiency of the polymer have been evaluated to achieve the isolation of 1-OHP from urine samples and to reduce non-specific interactions. Cross-selectivity was studied in the presence of other structural analogues of the 1-OHP as hydroxyphenantrene isomers. The method was validated over a concentration range of 0.15-2.00 µg L(-1), R(2)>0.998. Recovery values were in the range of 78-90% and RSD <6.7%. The limits of detection and quantification were 0.05 µg L(-1) and 0.17 µg L(-1), respectively. In our knowledge, it is the first time that this methodology is applied for analysing urinary hydroxypyrene and it has been demonstrated that this specific MISPE-HPLC-FLD method offers a fast and simple alternative to determine 1-OHP in human urine samples.


Assuntos
Impressão Molecular , Polímeros/síntese química , Pirenos/isolamento & purificação , Pirenos/urina , Extração em Fase Sólida/métodos , Acetonitrilas/química , Humanos , Recém-Nascido , Metacrilatos/química , Polimerização , Polímeros/química , Pirenos/química
18.
Bioresour Technol ; 192: 618-26, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26093256

RESUMO

The present study investigated the sorption of phenanthrene (PHE) and pyrene (PYR) by sewage sludges and sewage sludge-derived biochars. The organic carbon normalized distribution coefficient (log K(OC) for C(w) = 0.01 S(w)) for the sewage sludges ranged from 5.62 L kg(-1) to 5.64 L kg(-1) for PHE and from 5.72 L kg(-1) to 5.75 L kg(-1) for PYR. The conversion of sewage sludges into biochar significantly increased their sorption capacity. The value of log K(OC) for the biochars ranged from 5.54 L kg(-1) to 6.23 L kg(-1) for PHE and from 5.95 L kg(-1) to 6.52 L kg(-1) for PYR depending on temperature of pyrolysis. The dominant process was monolayer adsorption in the micropores and/or multilayer surface adsorption (in the mesopores), which was indicated by the significant correlations between log K(OC) and surface properties of biochars. PYR was sorbed better on the tested materials than PHE.


Assuntos
Carvão Vegetal/química , Fenantrenos/isolamento & purificação , Pirenos/isolamento & purificação , Esgotos/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Calefação/métodos , Teste de Materiais , Fenantrenos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Pirenos/química , Poluentes Químicos da Água/química
19.
J Environ Manage ; 156: 15-22, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25791233

RESUMO

In the present study, acrylic coupons with a thin layer of oil on the surface were incubated in the coastal water of Trindade Island, Brazil, for 60 days. The microorganisms adhered to the coupons were isolated using enrichment medium with hexadecane and naphthalene as the sole carbon and energy source. A total of 15 bacterial isolates were obtained, and the ability of these isolates to use different hydrocarbons as the source of carbon and energy was investigated. None of the isolates produced biosurfactants under our experimental conditions. Subsequently, identification methods such as partial sequencing of the 16S rRNA gene and analysis of fatty acids (MIDI) profile were employed. Among the 15 isolates, representatives of Actinobacteria, Firmicutes, and Alphaproteobacteria were detected. The isolates Rhodococcus rhodochrous TRN7 and Nocardia farcinica TRH1 were able to use all the hydrocarbons added to the culture medium (toluene, octane, xylene, naphthalene, phenanthrene, pyrene, hexadecane, anthracene, eicosane, tetracosane, triacontane, and pentacontane). Polymerase chain reaction amplification of the DNA isolated by employing primers for catechol 2,3-dioxygenase, alkane dehydrogenase and the alpha subunit of hydroxylating dioxygenases polycyclic aromatic hydrocarbon rings genes demonstrated that various isolates capable of utilizing hydrocarbons do not exhibit genes of known routes of catabolism, suggesting the existence of unknown catabolic pathways in these microorganisms. Our findings suggest that the microbiota associated to the coast of tropical oceanic islands has the ability to assist in environmental regeneration in cases of accidents involving oil spills in its shore. Thus, it motivates studies to map bioremediation strategies using the autochthonous microbiota from these environments.


Assuntos
Hidrocarbonetos/metabolismo , Microbiologia da Água , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Biodegradação Ambiental , Brasil , Primers do DNA , Dados de Sequência Molecular , Naftalenos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Reação em Cadeia da Polimerase , Pirenos/isolamento & purificação , Pirenos/metabolismo , RNA Ribossômico 16S/genética , Rhodococcus/classificação , Rhodococcus/genética , Rhodococcus/isolamento & purificação , Rhodococcus/metabolismo , Clima Tropical , Poluentes Químicos da Água/metabolismo
20.
Appl Biochem Biotechnol ; 175(2): 1123-38, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25369894

RESUMO

Fluoranthene and pyrene are polycyclic aromatic hydrocarbons of high molecular weight that are recalcitrant and toxic to humans; therefore, their removal from the environment is crucial. From hydrocarbon-contaminated soil, 25 bacteria and 12 filamentous fungi capable of growth on pyrene and fluoranthene as the sole carbon and energy source were isolated. From these isolates, Ochrobactrum anthropi BPyF3 and Fusarium sp. FPyF1 were selected and identified because they grew quickly and abundantly in both hydrocarbons. Furthermore, O. anthropi BPyF3 and Fusarium sp. FPyF1 were most efficient at removing pyrene (50.39 and 51.32 %, respectively) and fluoranthene (49.85 and 49.36 %, respectively) from an initial concentration of 50 mg L(-1) after 7 days of incubation. Based on this and on the fact that there was no antagonism between the two microorganisms, a coculture composed of O. anthropi BPyF3 and Fusarium sp. FPyF1 was formed to remove fluoranthene and pyrene at an initial concentration of 100 mg L(-1) in a removal kinetic assay during 21 days. Fluoranthene removal by the coculture was higher (87.95 %) compared with removal from the individual cultures (68.95 % for Fusarium sp. FPyF1 and 64.59 % for O. anthropi BPyF3). In contrast, pyrene removal by the coculture (99.68 %) was similar to that obtained by the pure culture of Fusarium sp. FPyF1 (99.75 %). The kinetics of removal for both compounds was adjusted to a first-order model. This work demonstrates that the coculture formed by Fusarium sp. FPyF1 and O. anthropi BPyF3 has greater potential to remove fluoranthene than individual cultures; however, pyrene can be removed efficiently by Fusarium sp. FPyF1 alone.


Assuntos
Técnicas de Cocultura , Fluorenos/isolamento & purificação , Fluorenos/metabolismo , Fusarium/metabolismo , Ochrobactrum anthropi/metabolismo , Pirenos/isolamento & purificação , Pirenos/metabolismo , Biodegradação Ambiental , Meios de Cultura/química , Poluentes Ambientais/isolamento & purificação , Poluentes Ambientais/metabolismo , Fusarium/crescimento & desenvolvimento , Cinética , Ochrobactrum anthropi/crescimento & desenvolvimento
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