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1.
Artigo em Inglês | MEDLINE | ID: mdl-37623145

RESUMO

Air pollution and the increasing production of greenhouse gases has prompted greater use of renewable energy sources; the EU has set a target that the use of green energy should be at 32 percent by 2030. With this in mind, in the last 10 years, the demand for pellets in Italy has more than doubled, making Italy the second largest consumer in Europe. The quality of the pellets burned in stoves is crucial to indoor and outdoor pollution. Among other parameters, moisture and ash are used to classify pellets according to EN ISO 17225:2014. This work involved the analysis of the organic and inorganic fraction of both some finished products on the Italian market and some raw materials (e.g., wood chips) sampled according to the technical standard EN 14778:2011. The analytical results showed the presence of some substances potentially harmful to human health such as formaldehyde, acetone, toluene and styrene for the organic fraction and nickel, lead and vanadium for the inorganic fraction. The chemometric approach showed that it is the inorganic fraction which is most responsible for the diversification of the samples under study. The detection of some substances may be a warning bell about the impact of such materials, both for the environment and for human health.


Assuntos
Poluição do Ar , Quimiometria , Humanos , Itália , Europa (Continente) , Acetona
2.
Toxics ; 11(3)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36977015

RESUMO

The emission of chemicals into the environment has increased in a not negligible way as a result of the phenomenon of globalization and industrialization, potentially also affecting areas always considered as "uncontaminated". In this paper, five "uncontaminated" areas were analyzed in terms of the presence of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs), comparing them with an "environmental blank". Chemical analyses were carried out using standardized protocols. The 'environmental blank' results revealed the presence of Cu (<64.9 µg g-1), Ni (<37.2 µg g-1), and Zn (<52.6 µg g-1) as HMs and fluorene (<17.0 ng g-1) and phenanthrene (<11.5 ng g-1) as PAHs. However, regarding the results of the pollution status of the areas under study, fluorene (#S1, 0.34 ng g-1; #S2, 4.3 ng g-1; #S3, 5.1 ng g-1; #S4, 3.4 ng g-1; #S5, 0.7 ng g-1) and phenanthrene (#S1, 0. 24 ng g-1; #S2, 3.1 ng g-1; #S3, 3.2 ng g-1; #S4, 3.3 ng g-1; #S5, 0.5 ng g-1) were found in all areas, while the other PAHs investigated were detected at a concentration averaging less than 3.3 ng g-1. HMs were found in all of the investigated areas. In particular, Cd was detected in all areas with an average concentration of less than 0.036 µg g-1, while Pb was absent in area #S5, but present in the other areas with an average concentration of less than 0.018 µg g-1.

3.
Environ Sci Pollut Res Int ; 30(15): 44234-44250, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36683105

RESUMO

Polycyclic aromatic hydrocarbons (PAHs), heavy metals, and plasticizer residues are continuously released into the environment. The use of living organisms, such as Apis mellifera L. and honey, is advantageous as bioindicator of the environmental health status, instead of traditional monitoring methods, showing the ability to record spatial and temporal pollutant variations. The PAHs and heavy metal presence were determined in two sampling years (2017 and 2018) in five different locations in the Molise region (Italy), characterized by different pollution levels. During 2017, most PAHs in all samples were lower than limit of detection (LOD), while in 2018, their mean concentration in bee and honey samples was of 3 µg kg-1 and 35 µg kg-1, respectively. For heavy metals, lower values were detected in 2017 (Be, Cd, and V below LOD), while in 2018, the mean concentrations were higher, 138 µg kg-1 and 69 µg kg-1, in bees and honey, respectively. Honey has been used as indicator of the presence of phthalate esters and bisphenol A in the environment. The satisfactory results confirmed that both bees and honey are an important tool for environmental monitoring. The chemometric analysis highlighted the differences in terms of pollutant concentration and variability in the different areas, validating the suitability of these matrices as bioindicators.


Assuntos
Poluentes Ambientais , Mel , Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Abelhas , Animais , Mel/análise , Biomarcadores Ambientais , Plastificantes/análise , Monitoramento Biológico , Hidrocarbonetos Policíclicos Aromáticos/análise , Metais Pesados/análise , Poluentes Ambientais/análise , Monitoramento Ambiental/métodos
4.
Front Microbiol ; 13: 973670, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979494

RESUMO

The active regulation of extracellular pH is critical for the virulence of fungal pathogens. Penicillium expansum is the causal agent of green-blue mold on stored pome fruits and during its infection process acidifies the host tissues by secreting organic acids. P. expansum is also the main producer of patulin (PAT), a mycotoxin found in pome fruit-based products and that represents a serious health hazard for its potential carcinogenicity. While it is known that PAT biosynthesis in P. expansum is regulated by nutritional factors such as carbon and nitrogen and by the pH, the mechanistic effects of biocontrol on PAT production by P. expansum are not known. In this work, we assessed how optimal and suboptimal concentrations of the biocontrol agent (BCA) Papiliotrema terrestris LS28 affect both extracellular pH and PAT biosynthesis in P. expansum. In wounded apples, the optimal and suboptimal concentrations of the BCA provided almost complete and partial protection from P. expansum infection, respectively, and reduced PAT contamination in both cases. However, the suboptimal concentration of the BCA increased the specific mycotoxigenic activity by P. expansum. In vitro, the rate of PAT biosynthesis was strictly related to the extracellular pH, with the highest amount of PAT detected in the pH range 4-7, whereas only traces were detectable at pH 3. Moreover, both in vitro and in apple wounds the BCA counteracted the extracellular P. expansum-driven acidification maintaining extracellular pH around 4, which is within the pH range that is optimal for PAT biosynthesis. Conversely, in the absence of LS28 the pathogen-driven acidification led to rapidly achieving acidic pH values (<3) that lie outside of the optimal pH range for PAT biosynthesis. Taken together, these results suggest that pH modulation by LS28 is important to counteract the host tissue acidification and, therefore, the virulence of P. expansum. On the other hand, the buffering of P. expansum-driven acidification provided by the BCA increases the specific rate of PAT biosynthesis through the extension of the time interval at which the pH value lies within the optimal range for PAT biosynthesis. Nevertheless, the antagonistic effect provided by the BCA greatly reduced the total amount of PAT.

5.
Foods ; 11(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35564074

RESUMO

Formaldehyde, the simplest molecule of the aldehyde group, is a gaseous compound at room temperature and pressure, is colorless, and has a strong, pungent odor. It is soluble in water, ethanol, and diethyl ether and is used in solution or polymerized form. Its maximum daily dosage established by the EPA is 0.2 µg g-1 of body weight whereas that established by the WHO is between 1.5 and 14 mg g-1: it is in category 1A of carcinogens by IARC. From an analytical point of view, formaldehyde is traditionally analyzed by HPLC with UV-Vis detection. Nowadays, the need to analyze this compound quickly and in situ is increasing. This work proposes a critical review of methods for analyzing formaldehyde in food using sensing methods. A search carried out on the Scopus database documented more than 50 papers published in the last 5 years. The increase in interest in the recognition of the presence of formaldehyde in food has occurred in recent years, above all due to an awareness of the damage it can cause to human health. This paper focuses on some new sensors by analyzing their performance and comparing them with various no-sensing methods but focusing on the determination of formaldehyde in food products. The sensors reported are of various types, but they all share a good LOD, good accuracy, and a reduced analysis time. Some of them are also biodegradable and others have a very low cost, many are portable and easy to use, therefore usable for the recognition of food adulterations on site.

6.
Ecotoxicol Environ Saf ; 239: 113619, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35605320

RESUMO

Phthalic acid esters (PAEs) are classified as endocrine disruptors, but it remains unclear if they can enter the marine food-web and result in severe health effects for organisms. Loggerhead turtles (Caretta caretta) can be chronically exposed to PAEs by ingesting plastic debris, but no information is available about PAEs levels in blood, and how these concentrations are related to diet during different life stages. This paper investigated, for the first time, six PAEs in blood of 18 wild-caught Mediterranean loggerhead turtles throughout solid-phase extraction coupled with gas chromatography-ion trap/mass spectrometry. Stable isotope analyses of carbon and nitrogen were also performed to assess the resource use pattern of loggerhead turtles. DEHP (12-63 ng mL-1) and DBP (6-57 ng mL-1) were the most frequently represented PAEs, followed by DiBP, DMP, DEP and DOP. The total PAEs concentration was highest in three turtles (124-260 ng mL-1) whereas three other turtles had concentrations below the detection limit. PAEs were clustered in three groups according to concentration in all samples: DEHP in the first group, DBP, DEP, and DiBP in the second group, and DOP and DMP in the third group. The total phthalates concentration did not differ between large-sized (96.3 ± 86.0 ng mL-1) and small-sized (67.1 ± 34.2 ng mL-1) turtles (p < 0.001). However, DMP and DEP were found only in large-sized turtles and DiBP and DBP had higher concentrations in large-sized turtles. On the other hand, DEHP and DOP were found in both small- and large-sized turtles with similar concentrations, i.e. ~ 21.0/32.0 ng mL-1 and ~ 7.1/9.9 ng mL-1, respectively. Winsored robust models indicated that δ13C is a good predictor for DBP and DiBP concentrations (significant Akaike Information criterion weight, AICwt). Our results indicate that blood is a good matrix to evaluate acute exposure to PAEs in marine turtles. Moreover, this approach is here suggested as a useful tool to explain the internal dose of PAEs in term of dietary habits (δ13C), suggesting that all marine species at high trophic levels may be particularly exposed to PAEs, despite their different dietary habitats and levels of exposure.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Tartarugas , Animais , Dieta , Dietilexilftalato/análise , Ecossistema , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Ftálicos/análise
7.
Data Brief ; 42: 108136, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35479420

RESUMO

This paper would like to show all the data related to an intensive field campaign focused on the characterization of the Polyaromatic Hydrocarbons (PAHs) composition profile in almost 60 honey samples collected in Central Italy. The analytical data here reported are the base for a study aimed to identify the pollution sources in a region. 22 PAHs were analyzed by means of ultrasound-vortex-assisted dispersive liquid-liquid micro-extraction (DLLME) procedure followed by a triple quadrupole gas chromatograph/mass spectrometer (GC-MS). A chemometrics approach has been carried out for evaluating all the data: in particular, principal component analysis and cluster analysis has been used both for the identification of the main natural/anthropogenic pollutants affecting a site and for evaluating the air quality.

8.
Food Chem ; 382: 132361, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35152011

RESUMO

The quality of honey is assessed through the determination of some commodity parameters: a certain importance is to be attributed to the absence of contaminating residues, in particular of Polycyclic Aromatic Hydrocarbons (PAHs). This paper deeply investigates the presence of 22 PAHs in 57 honey samples collected in Central Italy and identifies the possible source apportionment and fingerprint identification by DLLME-GC-MS analysis and a chemometric approach. Cluster Analysis and Principal Component Analysis have allowed to identify the main PAHs responsible of the contamination, benzo[a]anthracene and phenanthrene, characteristics pollutants of areas constantly exposed. The entire database has been compared to similar ones present in literature, particularly data from Serbia and Belgrado samples. The PCA applied to overall the data confirms the combustion to be the main contamination source in Italian samples whereas highlights the importance of the role of naphthalene, added during beekeeping practices in the other data-set.


Assuntos
Poluentes Ambientais , Mel , Hidrocarbonetos Policíclicos Aromáticos , Quimiometria , China , Monitoramento Ambiental , Poluentes Ambientais/análise , Mel/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
9.
Toxics ; 9(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34822670

RESUMO

The presence of phthalic acid esters (PAEs) in marine environments is an important issue. These chemicals are able to affect marine organisms, particularly marine turtles, and to act as endocrine disrupters. In this paper, for the first time, a simple and reproducible analytical method based on solid-phase extraction (SPE) coupled with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed for the extraction of phthalates from the blood of marine turtles. The extraction was obtained by using C18 phthalates-free as the stationary phase. In order to individuate the best working conditions for the extraction, the adsorption isotherms and breakthrough curves were studied. The overall analytical methodology was validated in terms of limit of detection (LOD, 0.08-0.6 ng mL-1), limit of quantification (LOQ, 0.4-0.8 ng mL-1), and correlation coefficients (>0.9933). By using this procedure, percentage recoveries ranging from 89 to 103% were achieved. The precision parameters (intra-day and inter-day) were studied, and the obtained values were smaller than 12.5%. These data confirm the goodness of the proposed analytical methodology, which is applied to real samples.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33567749

RESUMO

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid-liquid extraction and static headspace) followed by gas chromatography-electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L-1 in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g-1), antimony (77.7 µg g-1), strontium (12,039 µg g-1) and zinc (103 µg g-1), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g-1): the levels found in this paper (ranging between 1 and 5100 µg g-1) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.


Assuntos
Compostos Orgânicos Voláteis , Poluentes Químicos da Água , Monitoramento Ambiental , Itália , Rios , Água , Poluentes Químicos da Água/análise
11.
Methods Protoc ; 3(1)2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32213842

RESUMO

In this paper, an analytical protocol was developed for the simultaneous determination of phthalates (di-methyl phthalate DMP, di-ethyl phthalate DEP, di-isobutyl phthalate DiBP, di-n-butyl phthalate DBP, bis-(2-ethylhexyl) phthalate DEHP, di-n-octyl phthalate DNOP) and bisphenol A (BPA). The extraction technique used was the ultrasound vortex assisted dispersive liquid-liquid microextraction (UVA-DLLME). The method involves analyte extraction using 75 µL of benzene and subsequent analysis by gas chromatography combined with ion trap mass spectrometry (GC-IT/MS). The method is sensitive, reliable, and reproducible with a limit of detection (LOD) below 13 ng g-1 and limit of quantification (LOQ) below 22 ng g-1 and the intra- and inter-day errors below 7.2 and 9.3, respectively. The method developed and validated was applied to six honey samples (i.e., four single-use commercial ones and two home-made ones. Some phthalates were found in the samples at concentrations below the specific migration limits (SMLs). Furthermore, the commercial samples were subjected to two different thermal stresses (24 h and 48 h at 40 °C) for evidence of the release of plastic from the containers. An increase in the phthalate concentrations was observed, especially during the first phase of the shock, but the levels were still within the limits of the regulations.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32150918

RESUMO

Over the years, anthropogenic sources have increasingly affected food quality. One of the most sensitive and nutritional matrices affected by chemical contamination is honey, due to the use of acaricides. Recently, the attention has moved to the presence of phthalates (PAEs) and bisphenol A (BP-A), molecules present in plastic materials used both in the production phase and in the conservation of honey. In this study, an analytical method for the simultaneous determination of PAEs (dimethyl phthalate DMP, diethyl phthalate DEP, diisobutyl phthalate DiBP, dibutyl phthalate DBP, bis(2-ethylhexyl) phthalate DEHP, and di-n-octyl-phthalate DnOP) and BP-A was developed. The extraction technique is the ultrasound-vortex-assisted dispersive liquid-liquid microextraction (UVA-DLLME), using 150 µL of toluene as an extraction solvent, followed by the gas chromatography coupled with ion trap mass spectrometry analysis (GC-IT/MS). The developed method is sensitive, reliable, and reproducible: it shows high correlation coefficients (R > 0.999); limits of detection (LODs) less than 11 ng·g-1; limits of quantification (LOQs) less than 16 ng·g-1; repeatability below 3.6%, except BP-A (11.6%); and accuracy below 4.8%, except BP-A (17.6%). The method was applied to 47 nectar honey samples for evidencing similarities among them. The chemometric approach based on Hierarchical Cluster Analysis and Principal Component Analysis evidenced some similitudes about sample origin as well as marked differences between PAE and BP-A sources.


Assuntos
Mel , Ácidos Ftálicos , Plastificantes , Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Néctar de Plantas , Plastificantes/análise
13.
Sci Rep ; 9(1): 6429, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015563

RESUMO

Dittrichia viscosa (L.) Greuter, a perennial weed of the Mediterranean area, was reported to be source of active substances. Here, by means of both ingestion and contact assays, the biological activity of three different extracts (n-hexane, methanol, and distilled water) of D. viscosa aerial part has been evaluated against Sitophilus granarius (L.) adults, an important pest of stored grains. Ingestion assays showed negligible mortality and food deterrence for all the extracts, whereas only a slight reduction of some nutritional parameters (relative growth rate, relative consumption rate, food efficiency conversion) was recorded for water extract. High contact toxicity was found only for the n-hexane extract (24 h median lethal dose LD50 = 53.20 µg/adult). This extract was further subfractioned by silica gel column chromatography and then by thin layer chromatography. Further contact toxicity bioassays highlighted two active subfractions which were analyzed by GC-MS. This revealed the occurrence, in both subfractions, of two major peaks that were identified as α- and γ- costic acid isomers. Moreover, D. viscosa active subfractions, did not cause acetylcholinesterase (AChE) inhibition; therefore, in the light of progressive limitation of compounds acting by this mechanism of action, D. viscosa represents a promising eco-sustainable source of natural products for pest control.


Assuntos
Asteraceae/química , Produtos Biológicos/farmacologia , Inseticidas/farmacologia , Naftalenos/farmacologia , Gorgulhos/efeitos dos fármacos , Animais , Produtos Biológicos/isolamento & purificação , Relação Dose-Resposta a Droga , Grão Comestível/parasitologia , Cromatografia Gasosa-Espectrometria de Massas , Hexanos/química , Inseticidas/isolamento & purificação , Dose Letal Mediana , Longevidade/efeitos dos fármacos , Longevidade/fisiologia , Naftalenos/isolamento & purificação , Extratos Vegetais/química , Plantas Daninhas/química , Solventes/química , Gorgulhos/fisiologia
14.
Anal Bioanal Chem ; 410(14): 3285-3296, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29549507

RESUMO

Baby foods are either a soft, liquid paste or an easily chewed food since babies lack developed muscles and teeth to chew effectively. Babies typically move to consuming baby food once nursing or formula is not sufficient for the child's appetite. Some commercial baby foods have been criticized for their contents. This article focuses on the simultaneous determination of organophosphorus pesticides and phthalates by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with gas chromatography-ion trap mass spectrometry (GC-IT/MS). The protocol developed allowed the determination of six phthalates [dimethyl phthalate, diethyl phthalate, dibutyl phthalate, isobutyl cyclohexyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate] and 19 organophosphorus pesticides. Freeze-dried product samples (0.1-0.2 g) were dissolved in 10 mL of warm distilled water along with 5 µL of an internal standard (anthracene at 10 mg mL-1 in acetone): the choice of extraction solvent was studied, with the most suitable being n-heptane, which is used for phthalate determination in similar matrices. The solution, held for 5 min in a vortex mixer and for 6 min in a 100-W ultrasonic bath to favor solvent dispersion and consequently analyte extraction, was centrifuged at 4000 rpm for 30 min. Then 1 µL was injected into the GC-IT/MS system (SE-54 capillary column; length 30 m, inner diameter 250 µm, film thickness 0.25 µm). All analytical parameters investigated are discussed in depth. The method was applied to real commercial freeze-dried samples: significant contaminant concentrations were not found. Graphical abstract Simultaneous and sensitive determination of organophosphorus pesticides and phthalates in baby foods by the ultrasound-vortex-assisted liquid-liquid microextraction Öªgas chromatography-ion trap mass spectrometry procedure. 1 methacrifos, 2 pirofos, 3 phorate, 4 seraphos, 5 diazinon, 6 etrimphos, 7 dichlofenthion, 8 chlorpyrifos-methyl, 9 pirimiphos-methyl, 10 malathion, 11 chlorpyrifos, 12 parathion-ethyl, 13 pirimiphos-ethyl, 14 bromophos, 15 chlorfenvinphos, 16 bromophos-ethyl, 17 stirophos, 18 diethion, 19 coumaphos, A dimethyl phthalate, B diethyl phthalate, C dibutyl phthalate, D butyl cyclohexyl phthalate, E benzyl butyl phthalate, F bis(2-ethylhexyl) phthalate, IS internal standard.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Alimentos Infantis/análise , Microextração em Fase Líquida/métodos , Compostos Organofosforados/análise , Praguicidas/análise , Ácidos Ftálicos/análise , Humanos , Recém-Nascido , Limite de Detecção , Sonicação/métodos
15.
J Chromatogr A ; 1474: 1-7, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-28314431

RESUMO

This paper is focused on the determination of phthalates (PAEs), compounds "plausibly" endocrine disruptors, in baby food products by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with GC-IT/MS (UVALLME-GC-IT/MS). Particularly, the whole procedure allows the determination of six phthalates such as DMP, DEP, DBP, iBcEP, BBP and DEHP. After dissolution of 0.1g product sample and addition of anthracene as Internal Standard, 250µL of n-heptane are used as extraction solvent. The solution, held for 5min on the vortex mixer and for 6min in an ultrasonic bath at 100W for favoring the solvent dispersion and consequently the analyte extraction, is centrifuged at 4000rpm for 30min. About 100µL of heptane are recovered and 1µL is injected into the GC-IT/MS. All the analytical parameters investigated are deeply discussed: under the best conditions, the percentage recoveries range between 96.2 and 109.2% with an RSD ≤10.5% whereas the Limit of Detections (LODs) and the Limit of Quantifications (LOQs) are below 11 and 20ngg-1, respectively, for all the PAEs except for iBcEP (23 and 43ngg-1, respectively). The linear dynamic range of this procedure is between 10 and 5000ngg-1 with R2 ≥0.92. The method has been applied to real commercial freeze-dried samples (chicken and turkey meats) available on the Italian pharmaceutical market: three PAEs were preliminary identified, i.e. DEP (14ngg-1), DBP (11ngg-1) and DEHP (64ngg-1).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Alimentos Infantis/análise , Microextração em Fase Líquida/métodos , Ácidos Ftálicos/análise , Animais , Antracenos/análise , Galinhas , Disruptores Endócrinos/análise , Liofilização , Heptanos/química , Limite de Detecção , Carne/análise , Padrões de Referência , Solventes/química , Fatores de Tempo , Perus , Ultrassom
16.
Food Chem ; 146: 181-7, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176330

RESUMO

An analytical method based on solid-phase extraction (SPE) with Amberlite XAD-2 adsorbent used as stationary phase for determining phthalate esters (PAEs) in hydroalcoholic food beverages by GC-FID (and peak confirmation by GC-IT/MS) has been set up. The XAD-2 resin shows excellent properties for determining PAEs in solutions at very large alcoholic range (10-40% v/v): 500mL of hydroalcoholic solution spiked with a PAE mixture solution (20pgµL(-1) of each PAE) and containing 25gL(-1) of NaCl are passed onto a cartridge containing 500mg XAD-2 adsorbent and re-extracted for GC analysis. The effects of NaCl concentration (0, 12, 25 and 50gL(-1)) and different solvents (CS2, toluene, acetone, n-hexane, ethyl acetate) are extensively studied as well the PAE recoveries both in hydroalcoholic aqueous solutions (ranging between 94% and 103% with a Relative Standard Deviation, RSD, below 8.3) and spiked (5, 10 and 25pgµL(-1) of each PAE) real samples (between 90% and 106% with a RSD below 9.9). The correlation coefficients (R(2)) of each PAE vary between 0.9830 and 0.9950 and they are calculated in the linear range 5-100pgµL(-1). The limits of detection (LOD) in GC-FID vary between 1.21 and 2.51pgµL(-1) (RSD⩽11.1) whereas the Limits of Quantification (LOQ) range between 2.42 and 5.03pgµL(-1) (RSD⩽8.9) whereas the infra-day and inter-day repeatabilities calculated as RSD for hydroalcoholic solutions, are between 6.5% and 13.7%.


Assuntos
Bebidas Alcoólicas/análise , Ésteres/análise , Ésteres/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida/métodos , Adsorção , Ionização de Chama , Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Limite de Detecção , Ácidos Ftálicos/análise , Poliestirenos/química , Extração em Fase Sólida/instrumentação
17.
Food Chem ; 146: 204-11, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176333

RESUMO

A new, simple, rapid and fully validated method based on gas chromatography coupled with Electron capture and ion trap mass spectrometry detectors (GC-ECD and GC-IT/MS) is presented for quantitative analysis of acrylamide contaminant in conventional cereal-based foods and potato chips. Before analysis acrylamide was efficiently derivatized with trifluoroacetic anhydride, the effects of temperature, reaction time and catalyst on the acylation reaction were evaluated. Chromatographic analysis was performed on SE-54 capillary column; good retention and peak response of the acrylamide derivative achieved under the optimal conditions. The analytical method has been fully validated by assessment of the following parameters: LODs and LOQs (1 and 25ngg(-1) by GC-ECD and 2 and 36ngg(-1) by GC-IT/MS, with a Relative Standard Deviations <4 and <6, respectively), linearity (R(2) above 0.981 in the range 0.005-50µgg(-1)) and extraction recovery (ranging between 91% and 99%, RSD below 4.0, for acrylamide spiked at levels of 1, 20, 50 and 100ngg(-1)). Furthermore, the method proposed requires no clean-up step of the acrylamide derivative to be performed prior to injection. The developed method has been successfully applied to determine acrylamide in different commercial cereal-based foods (including French fries and potato chips).


Assuntos
Acrilamida/química , Grão Comestível/química , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Solanum tuberosum/química
18.
Anal Bioanal Chem ; 405(18): 6137-41, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23660693

RESUMO

This paper proposes a new method for quantitative analysis of acrylamide in cereal-based foods and potato chips. The method uses reaction with trifluoroacetic anhydride, and analyses the resulting derivative by use of gas chromatography with electron-capture detection (GC-ECD). The effects of derivatization conditions, including temperature, reaction time, and catalyst, on the acylation reaction were evaluated. Chromatographic analysis was performed on an SE-54 capillary column. Under the optimum conditions, good retention and peak response were achieved for the acrylamide derivative. The analytical method was fully validated by assessment of LODs and LOQs (1 ng g(-1) and 25 ng g(-1), with relative standard deviations (RSD) 2.1 and 3.6, respectively), linearity (R = 0.9935 over the range 0.03-10 µg g(-1)), and extraction recovery (>96%, with RSD below 2.0, for acrylamide spiked at 1, 20, 50, and 100 ng g(-1); 99.8% for acrylamide content >1000 ng g(-1)). The method requires no clean-up of the acrylamide derivative before injection. The method has been successfully used to determine acrylamide levels in different commercial cereal-based foods, French fries, and potato chips.


Assuntos
Acrilamida/análise , Cromatografia Gasosa/métodos , Grão Comestível/química , Contaminação de Alimentos/análise , Anidridos Acéticos/química , Cromatografia Gasosa/instrumentação , Fluoracetatos/química , Limite de Detecção
19.
J Sep Sci ; 36(14): 2260-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23640871

RESUMO

GC column selectivity can be continuously adapted to suit analytical needs using a flow-tuneable tandem system. Its application for the separation of complex mixtures requires a deep understanding of the theory in this area. Although a number of researchers have developed specific models, a general and exhaustive theory is still missing. In this paper, we have made an implementation of pre-existing models on tandem-column assemblies operated isothermally. In particular, we have investigated the effect of column length and diameter, phase thickness, and oven temperature on chromatographic parameters, such as capacity factor, selectivity, and intrinsic resolution. A new approach for the correct choice of the working temperature has been proposed.

20.
Anal Chim Acta ; 769: 72-8, 2013 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-23498123

RESUMO

An Ultrasound-Vortex-Assisted Dispersive Liquid-Liquid Micro-Extraction (USVADLLME) procedure coupled with Gas Chromatography-Flame Ionization Detector (GC-FID) or Gas Chromatography-Ion Trap Mass Spectrometry (GC-IT/MS) is proposed for rapid analysis of six phthalate esters in hydroalcoholic beverages (alcohol by volume, alc vol(-1), ≤40%). Under optimal conditions, the enrichment factor of the six analytes ranges from 220- to 300-fold and the recovery from 85% to 100.5%. The limit of detection (LOD) and limit of quantification (LOQ) are ≥0.022 µg L(-1) and ≥0.075 µg L(-1), respectively. Intra-day and inter-day precisions expressed as relative standard deviation (RSD), are ≤8.2% and ≤7.0%, respectively. The whole proposed methodology has demonstrated to be simple, reproducible and sensible for the determination of trace phthalate esters in red and white wine samples.

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