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1.
Food Chem X ; 22: 101399, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38840722

RESUMO

The aim of this study deals with characterize the volatile profiles of gluten free flours and bakery products. An appropriate HS-SPME/GC-MS methods for the quantification analyses was performed and corn starch solid as standards was used. 34 different samples were analysed, and 127 compounds distributed in 4 classes (alcohols, aldehydes and ketones, heterocyclic compounds, and terpenes), that make up the aroma of these gluten free, were identified. The developed method is characterized by detection limits of 0.0004 and 0.0047 mg/kg for camphor and pyrazine, respectively, and linearity of quantification standards were between 0.990 and 0.998 for a range of 3-50 mg/kg.

2.
J Cosmet Dermatol ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898670

RESUMO

BACKGROUND: Titanium dioxide (TiO2), a white powder, represents the opacifier used in many products, including drugs, foods, cosmetics, paints, and dyes. METHOD: The Uv-Vis spectrophotometry was a particularly suitable technique to quantify TiO2 in the solutions obtained from cosmetics. In this work, we determined the TiO2 content in a total of 88 samples of eye shadows and face powders of different brands and costs. Before to analyse the samples, we developed the mineralization and analysis method, in fact, fusion with potassium bisulphate would be very laborious because it must be carried out on one sample at a time and requires very long times, instead, the mineralization with the acid mixture and the aid of microwaves allowed us to solubilize six samples at the same time within 45 min. RESULTS: From the results obtained, we can state that the highest concentrations of TiO2 are found in the eyeshadows with a maximum value of 36% in a blue eyeshadow.

3.
Toxics ; 12(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38250983

RESUMO

Perfluorooctanoic acid (PFOA) in environmental matrices is increasingly being studied due to its environmental persistence, global occurrence, bioaccumulation, and associated human health risks. Some indoor environments can significantly impact the health of occupants due to pollutants in indoor air and household dust. To investigate the potential exposure of individuals to PFOA in specific confined environments, this study reports an analytical method and results concerning the determination of PFOA in household dust, used as a passive sampler. To the best of our knowledge, this paper represents one of the first studies concerning PFOA concentrations in indoor dust collected in the south of Italy, within the European region. A total of twenty-three dust samples were collected from two different areas of Sicily (Palermo and Milena), extracted, and analyzed by an UHPLC-QTOF-MS/MS system. Finally, PFOA exposure was estimated using a new index (Indoor PFOA Exposure Index, IPEX) that incorporates the PFOA levels in dust, exposure time, and the correlation between the PFOA in dust and blood. It was then compared across four different exposure groups, revealing that PFOA exposure for people working in chemistry laboratories was evaluated to be ten times higher than the exposure for homemakers.

4.
ChemistryOpen ; 11(12): e202200082, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36478441

RESUMO

Several phthalate acid esters (PAEs), often called phthalate esters or phthalates, are substances classified as harmful due to their carcinogenic and mutagenic properties, and moreover, as dangerous for humans because they interfere with the endocrine system. In general, phthalic esters are used as plasticizers for different polymers and more other consumer products. In the present study, we describe a simple method to quantify PAEs in coffee brew using a liquid-liquid extraction without purification processes through analysing the obtained organic phase by GCMS in the single ion monitoring mode. The totals of single PAEs, in coffee brew samples analysed by us, are in the range of 159-5305 µg L-1 . Considering that, on average, a person drinks three cups (total 90 mL) of the aforementioned drink per day, this will lead to the uptake of a total 14 to 477 µg of phthalates.


Assuntos
Café , Ésteres , Humanos , Cromatografia Gasosa-Espectrometria de Massas
5.
Molecules ; 25(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007913

RESUMO

Two mononuclear Pd(II) complexes [PdCl2(pfptp)] (1) and [PdCl2(pfhtp)] (2), with ligands 2-(3-perfluoropropyl-1-methyl-1,2,4-triazole-5yl)-pyridine (pfptp) and 2-(3-perfluoroheptyl-1-methyl-1,2,4-triazole-5yl)-pyridine (pfhtp), were synthesized and structurally characterized. The two complexes showed a bidentate coordination of the ligand occurring through N atom of pyridine ring and N4 atom of 1,2,4-triazole. Both complexes showed antimicrobial activity when tested against both Gram-negative and Gram-positive bacterial strains.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Fluorocarbonos/síntese química , Fluorocarbonos/farmacologia , Compostos Heterocíclicos/síntese química , Paládio/química , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , DNA/genética , Fluorocarbonos/química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho
6.
Foods ; 8(2)2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30764564

RESUMO

Potato is a starchy, tuberous crop from the perennial Solanum tuberosum having high nutritional values. This paper is the first analytical approach to quantify Pt and Rh in vegetal food. In this study a total of 38 different potato samples produced in Europe and one in Australia were investigated. Determinations of Pt and Rh in potato samples were carried out by Differential pulse voltammetry (DPV/a) for platinum and by Adsorptive stripping voltammetry (AdSV) for Rh using standard addition procedure. Because no certified reference potatoes containing platinum and rhodium are available, we used addition standard method. The quantification limits for Pt and Rh are 0.007 and 0.0008 µg kg-1 respectively. Considering all the potato samples, concentrations of Pt and Rh vary in the ranges from 0.007 to 109 µg kg-1 (sample no, 6 potatoes grown in Sicily) and from 0.0008 to 0.030 µg kg-1 (sample no. 3 of potatoes grown in Emilia Romagna), respectively. For both metals, in many cases the concentrations fall near the quantification limit. In all the samples, platinum is always more abundant than rhodium and their mean ratio is 14,500, which is much greater than that of the Earth's crust (about 100).

7.
Nat Prod Res ; 33(7): 947-955, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26611259

RESUMO

This preliminary study has mainly focused on the wax identification by nuclear magnetic resonance (NMR) and removal. Wax is used for many purposes in the field of art as protective coatings on wooden, stone or metal objects. From the comparison of the spectra H NMR and in particular with the correspondence of the resonance peaks of the samples taken from the statue and beeswax and paraffin, we can conclude that the wax applied on the statue surface is beeswax. From our data, it can be concluded that, to remove the beeswax, from any stone support, the more effective solvent is the mixture of cyclohexane/ethyl acetate. The removal percentages ranged from 19 to 99%. Lower percentages of removal have been observed in the case of yellow marble, probably because of its high porosity. We can affirm that, this solvent mixture can be employed in real art objects using cotton swabs to remove protective wax.


Assuntos
Arte , Carbonato de Cálcio , Ceras/isolamento & purificação , Acetatos/química , Cicloexanos/química , Espectroscopia de Ressonância Magnética , Parafina/isolamento & purificação , Porosidade , Solventes/química
8.
Foods ; 7(6)2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925768

RESUMO

The aim of this study (first analytical approach) was to obtain data concerning the fatty acid composition of gluten-free foods (bakery products) for celiac people. The study included 35 different products (snacks, biscuits, bakery products, pasta, flours, etc.) from several manufacturers. After extraction and esterification, the fatty acid composition was determined by Gaschromatography (GC⁻MS) Monounsaturated fatty acids (MUFAs) were found to be the major constituents (57%), followed by saturated fatty acids (SFAs) (30%), and polyunsaturated fatty acid (13%). Only 15 of the 35 gluten-free samples analyzed appeared to provide adequate energy intake, while, in 11 samples, saturated fatty acids were found to supply more energy than that recommended by the European Food Safety Authority EFSA. Moreover, data analyses showed that, although gluten-free commercial products are high added-value foods, industrial products in many cases contain palm and palm kernel oils, whereas the local producers generally use the finest raw materials, such as olive oil.

9.
Environ Sci Pollut Res Int ; 24(20): 16869-16882, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28573564

RESUMO

The aim of this study was to obtain information on the presence and levels of hazardous organic pollutants in groundwater located close to solid waste landfills. Eighty-two environmental contaminants, including 16 polycyclic aromatic hydrocarbons (PAHs), 20 volatile organic compounds (VOCs), 29 polychlorinated biphenyls (PCBs), 7 dioxins (polychlorinated dibenzo-p-dioxins, PCDDs) and 10 furans (polychlorinated dibenzofurans, PCDFs) were monitored in areas characterised by different geological environments surrounding three municipal solid waste landfills (Palermo, Siculiana and Ragusa) in Sicily (Italy) in three sampling campaigns. The total concentrations of the 16 PAHs were always below the legal threshold. Overall, the Fl/Fl + Py diagnostic ratio revealed that PAHs had a petrogenic origin. VOC levels, except for two notable exceptions near Palermo landfill, were always below the legal limit. As concerns PCB levels, several samples were found positive with levels exceeding the legal limits. It is worth noting that the % PCB distribution differs from that of commercial compositions. In parallel, some samples of groundwater containing PCDDs and PCDFs exceeding the legal threshold were also found. Among the 17 congeners monitored, the most abundant were the highest molecular weight ones.


Assuntos
Água Subterrânea , Resíduos Sólidos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Benzofuranos , Itália , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Sicília
10.
Bioorg Med Chem ; 25(8): 2378-2386, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28336408

RESUMO

Mono- and binuclear Pt(II) and Pd(II) complexes with 2,2'-dithiobis(benzothiazole) (DTBTA) ligand are reported. [Pt(DTBTA)(DMSO)Cl]Cl∙CHCl3 (1) and [Pd2(µ-Cl)2(DTBTA)2]Cl2 (2) have been synthesized and structurally characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, MS spectrometry and the content of platinum and palladium was determined using a flame atomic spectrometer. Two different coordination modes of 1 and 2 complexes were found; in both complexes, the coordination of Pt(II) and Pd(II) ions involves the N(3) atoms of the ligand but the binuclear complex 2, is a cis-chloro-bridged palladium complex. Evaluation of their in vitro antitumor activity against two human tumor cell lines human breast cancer (MCF-7) and hepatocellular carcinoma (HepG2); and their antimicrobial activity against Escherichia coli and Kokuria rhizophila was performed. Only complex 1 showed a dose- and time-dependent cytotoxic activity against the two tumor cell lines, associated to apoptosis and accumulation of treated cells in G0/G1 phase of cell cycle, while both 1 and 2 exhibited antimicrobial activity with complex 1 much more potent. The study on intracellular uptake in both MCF-7 and HepG2 cell lines revealed that only platinum of complex 1 is present inside the cells, suggesting a different mode of action of the two compounds. This was also in agreement with the results obtained for the antitumor and antibacterial activity.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Benzotiazóis/farmacologia , Paládio/química , Paládio/farmacologia , Compostos de Platina/química , Compostos de Platina/farmacologia , Antibacterianos/síntese química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli/efeitos dos fármacos , Humanos , Ligantes , Testes de Sensibilidade Microbiana , Compostos de Platina/síntese química , Análise Espectral
11.
Artigo em Inglês | MEDLINE | ID: mdl-28212294

RESUMO

The objective of present study was to identify volatile organic compounds (VOCs) emitted from several sources (fuels, traffic, landfills, coffee roasting, a street-food laboratory, building work, indoor use of incense and candles, a dental laboratory, etc.) located in Palermo (Italy) by using canister autosamplers and gas chromatography-mass spectrometry (GC-MS) technique. In this study, 181 VOCs were monitored. In the atmosphere of Palermo city, propane, butane, isopentane, methyl pentane, hexane, benzene, toluene, meta- and para-xylene, 1,2,4 trimethyl benzene, 1,3,5 trimethyl benzene, ethylbenzene, 4 ethyl toluene and heptane were identified and quantified in all sampling sites.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Cidades , Monitoramento Ambiental/métodos , Itália
12.
Environ Sci Process Impacts ; 18(3): 323-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26780160

RESUMO

Vanadium (V) concentrations in industrial, urban and volcanic soils were sequentially extracted using a modified Tessier's method. The voltammetric technique was used to determine V concentrations in solutions obtained from the various extraction steps. At the reference stations, the V concentrations (sum of four individual fractions) in soils ranged from 0.72 to 0.24 g kg(-1) dry weight (d.w.) with a mean value of 0.18 g kg(-1) d.w. V concentrations in soils of the Palermo urban area ranged from 0.34 to 2.1 g kg(-1) d.w., in the Milazzo (industrial) area between 0.26 and 5.4 g kg(-1) d.w. and in the volcanic area near Mt. Etna from 0.91 to 2.9 g kg(-1) d.w. When the V concentrations around Mt. Etna were compared with those obtained at the reference stations, it was confirmed that Mt. Etna is a continuous source of V. In all the samples analyzed, the majority of V (from 94 to 100%) was detected in the fourth fraction.


Assuntos
Poluentes do Solo/análise , Vanádio/análise , Fracionamento Químico , Cidades , Técnicas Eletroquímicas , Monitoramento Ambiental , Indústrias , Itália , Erupções Vulcânicas
13.
Nat Prod Res ; 30(18): 2107-10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26566684

RESUMO

Twenty-one almond samples from three different geographical origins (Sicily, Spain and California) were investigated by determining minerals and fatty acids compositions. Data were used to discriminate by chemometry almond origin by linear discriminant analysis. With respect to previous PCA profiling studies, this work provides a simpler analytical protocol for the identification of almonds geographical origin. Classification by using mineral contents data only was correct in 77% of the samples, while, by using fatty acid profiles, the percentages of samples correctly classified reached 82%. The coupling of mineral contents and fatty acid profiles lead to an increased efficiency of the classification with 87% of samples correctly classified.


Assuntos
Ácidos Graxos/análise , Minerais/análise , Prunus dulcis/química , California , Geografia , Sicília , Espanha
14.
J Toxicol Environ Health A ; 78(15): 1008-18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26262443

RESUMO

A simple and fast method is proposed to analyze commercial personal perfumes. Our method includes measurement of phthalates, known to be major sources of endocrine disruptor chemicals (EDC), which originate from the less volatile fraction of perfumes. The quantification of phthalates were carried out directly with no sample preparation required on 30 samples of commercial products using gas chromatography and mass spectrometry (GC-MS) as a detector. The total concentrations of 15 investigated compounds ranged from 17 to 9650 mg/L with an average of 2643 mg/L. The highest total concentration was found in cologne. Diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di(2-ethylhexyl) phthalate (DEHP), and di-n-butyl phthalate (DBP) were detected in appreciable concentrations. Further, it was found that the composition of counterfeit samples varied widely from that of authentic products. The composition of old products was different from that of recent perfumes, which contain less harmful chemicals, attributed to the ban on some phthalates in Europe due their toxicity. It should be noted that older and contaminated products are not equivalent to authentic products when considering quality, safety, and probably effectiveness. Older and nonapproved perfumes contain chemicals that are not allowed for commercial use and may contain toxic impurities.


Assuntos
Disruptores Endócrinos/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Perfumes/química , Ácidos Ftálicos/análise
15.
Environ Sci Pollut Res Int ; 22(3): 1891-905, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25226838

RESUMO

In this work, we studied the influence of air pollution on the morpho-structural, biochemical and chemical composition of Eucalyptus camaldulensis leaves. Analyses were carried out on 22 samples collected in Palermo (Italy) area. Considering the mean concentrations (in unwashed leaves) of investigated metals, nutrient elements as Fe (214 mg kg(-1) dry weight (d.w.)), Mn (160 mg kg(-1) d.w.) and Zn (39 mg kg(-1) d.w.) were the most abundant, whereas Pb (5.6 mg kg(-1) d.w.) and Cd (0.072 mg kg(-1) d.w.) showed the lowest concentrations. The values of metal pollution index (MPI) ranged from 6.0 (station no. 15) to 25 (station no. 8) and from 4.0 (station no. 16) to 17 (stations no. 7 and no. 15) for unwashed and washed leaves, respectively. The station no. 8, located in an area interested by traffic mostly caused by the activities of university, showed the highest value of MPI. The station no. 15 (Industrial area) showed the lowest MPI value, which is similar to those determined in the reference stations. Considering that the station considered is located in a large and open area interested only by commercial activities and there are no production activities, this data is not surprising. In this study, the washing of the leaves with distilled water has caused a little reduction of metal concentrations. Microphotography reveals a correlation between zones of necrosis, modified cuticles and accumulations of acid phosphatases in the leaves collected in polluted areas. The diaphanized leaves from the more polluted areas show irregular areolas, several idioblasts both on the ribs and scattered in the mesophyll. With polarized light, we observe many crystal deposits near the ribs.


Assuntos
Poluentes Atmosféricos/análise , Eucalyptus , Metais Pesados/análise , Monitoramento Ambiental , Eucalyptus/química , Eucalyptus/citologia , Itália , Folhas de Planta/química , Folhas de Planta/citologia , Pólen/química , Espectrofotometria/métodos
16.
Talanta ; 129: 263-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25127593

RESUMO

Due to worker׳s exposure, solvent and stationary phases׳ consumption, sample purification is one of the most polluting steps in analytical procedures for determination of organic pollutants in real samples. The use of photochemical sample treatment represents a valid alternative methodology for extracts clean up allowing for a reduction of the used amount of organic solvents. In this paper we report the first application on the photolytic destruction of organic substances to eliminate some of the interferences in the analysis of Chlorobenzenes in sediment samples. The method׳s efficiency and robustness were compared with classic silica column purification process currently used in clean up procedures in sediment analysis. Quality parameters such as recovery, linearity and reproducibility were studied. The entire procedure was validated by three replicate analysis of spiked real sediment sample. The quantification limits (LOQ) obtained by us ranged from 1.0 to 2.3 ng g(-1), while the detection limits (LOD) were of 1.0 ng g(-1). The RSD for each congener was below 10% and recoveries were in the range 95-130%. Results based on the analysis of real samples showed similar or improved detection thresholds and pointed out the advantages of the photochemical methodology in terms of costs, use of chemical substances and operator׳s safety according to Green Analytical Chemistry principles.


Assuntos
Clorobenzenos/análise , Sedimentos Geológicos/química , Química Verde , Fotoquímica/métodos , Cromatografia , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Reprodutibilidade dos Testes , Poluentes do Solo/análise , Solventes/química , Manejo de Espécimes , Temperatura , Água/química
17.
Chempluschem ; 79(3): 421-426, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31986604

RESUMO

Five imidazolium-based materials have been synthesised and used for the first time as palladium scavengers. Radical reactions of suitable bis-vinylimidazolium salts led to a series of insoluble materials through homo-polymerisation, immobilisation with a 3-mercaptopropyl-modified silica gel or co-polymerisation with ethylene glycol dimethylacrylate. These materials were screened as palladium scavengers with a set of palladium(0) and palladium(II) compounds in different solvents and at different starting amounts of palladium. In many cases, residual amounts of palladium were lower than 5 ppm, as requested for the manufacture of active pharmaceutical ingredients and fine chemicals. The application of one of these materials as a palladium scavenger in a Suzuki coupling reaction resulted in a 29-fold abatement of the palladium content in the final product with respect to the control reaction.

18.
Environ Geochem Health ; 35(5): 613-24, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23807633

RESUMO

In this work, phthalic acid esters (PAEs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate, and di-n-octyl phthalate in indoor dust (used as passive sampler) were investigated. The settled dust samples were collected from thirteen indoor environments from Palermo city. A fast and simple method using Soxhlet and GC-MS analysis has been optimized to identify and quantify the phthalates. Total phthalates concentrations in indoor dusts ranged from 269 to 4,831 mg/kg d.w. (d.w. = dry weight). The data show a linear correlation between total PAEs concentration and a single compound content, with the exclusion of the two most volatile components (DMP and DEP) that are present in appreciable amounts only in two samples. These results suggest that most of the PAEs identified in the samples of settled dust originate from the same type of material. This evidence indicates that, in a specific indoor environment, generally is not present only one compound but a mixture having over time comparable percentages of PAEs. Consequently, for routine analyses of a specific indoor environment, only a smaller number of compounds could be determined to value the contamination of that environment. We also note differences in phthalate concentrations between buildings from different construction periods; the total concentration of PAEs was higher in ancient homes compared to those constructed later. This is due to a trend to reduce or remove certain hazardous compounds from building materials and consumer goods. A linear correlation between total PAEs concentration and age of the building was observed (R = 0.71).


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Monitoramento Ambiental/métodos , Ácidos Ftálicos/análise , Cidades , Ésteres , Cromatografia Gasosa-Espectrometria de Massas , Itália
19.
Environ Monit Assess ; 185(7): 5551-62, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23096137

RESUMO

This paper describes a work aimed at improving the conditions of an extraction method, coupling GC-MS determination, for the analysis without cleanup phase, of polycyclic aromatic hydrocarbons (PAHs) from sediment samples. The automatic Soxhlet extraction in warm mode (using Extraction System B-811 Standard, Büchi) has demonstrated advantages for automation, reduced extraction time, and lower solvent use than for conventional Soxhlet extraction. Under these conditions, the recoveries are very good as they resulted greater than 85% and, in most of the cases, near 100%. The repeatability is also satisfactory (relative standard deviation less than 15%). The detection limits are also acceptable and ranged from 0.001 to0.01 µg/kg dry weight. Fifty-four sediment samples were collected. The total concentration of the 17 compounds investigated, in samples of sediments collected from three Sicilian coastal areas, expressed as the sum of concentrations, varies from 99 to 11,557 µg/kg of dry matrix; concentrations of total PAHs in the sediments of Cala are two to three times higher than the other stations.


Assuntos
Fracionamento Químico/métodos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas , Água do Mar/química , Sicília
20.
Talanta ; 103: 349-54, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23200398

RESUMO

Sample purification can be considered the most polluting step of the whole analytical process for PCBs determination in sediment samples. The use of photochemical sample treatment represents an alternative methodology for extracts clean up allowing for a reduction of the used amount of organic solvents. The first application of a photochemical sample treatment for the selective removal or reduction of organic substances interfering with PCBs analyses in sediments is reported. The method's efficiency and robustness were compared with currently used chromatographic purification. Quality parameters such as recovery, linearity and reproducibility were studied. The entire procedure was validated by four replicate analysis of certified reference sediment. The quantification limits (LOQ) obtained by us ranged from 1 to 3.1 ng g(-1). The RSD for each congener was below 15% and recoveries were in the range 40-130%. Results based on the analysis of real and certified samples showed similar or improved detection thresholds and pointed out the advantages of the photochemical methodology in terms of costs and environmental friendly conditions.


Assuntos
Sedimentos Geológicos/análise , Fotoquímica , Bifenilos Policlorados/análise , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/química , Bifenilos Policlorados/química , Bifenilos Policlorados/isolamento & purificação
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