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Sample records for spme headspace analysis

  1. Development of a Direct Headspace Collection Method from Arabidopsis Seedlings Using HS-SPME-GC-TOF-MS Analysis

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    Kazuki Saito

    2013-04-01

    Full Text Available Plants produce various volatile organic compounds (VOCs, which are thought to be a crucial factor in their interactions with harmful insects, plants and animals. Composition of VOCs may differ when plants are grown under different nutrient conditions, i.e., macronutrient-deficient conditions. However, in plants, relationships between macronutrient assimilation and VOC composition remain unclear. In order to identify the kinds of VOCs that can be emitted when plants are grown under various environmental conditions, we established a conventional method for VOC profiling in Arabidopsis thaliana (Arabidopsis involving headspace-solid-phase microextraction-gas chromatography-time-of-flight-mass spectrometry (HS-SPME-GC-TOF-MS. We grew Arabidopsis seedlings in an HS vial to directly perform HS analysis. To maximize the analytical performance of VOCs, we optimized the extraction method and the analytical conditions of HP-SPME-GC-TOF-MS. Using the optimized method, we conducted VOC profiling of Arabidopsis seedlings, which were grown under two different nutrition conditions, nutrition-rich and nutrition-deficient conditions. The VOC profiles clearly showed a distinct pattern with respect to each condition. This study suggests that HS-SPME-GC-TOF-MS analysis has immense potential to detect changes in the levels of VOCs in not only Arabidopsis, but other plants grown under various environmental conditions.

  2. Analysis of the volatiles in the headspace above the plasmodium and sporangia of the slime mould (Physarum polycephalum) by SPME-GCMS

    OpenAIRE

    Kateb, Huda al; Costello, Ben de Lacy

    2013-01-01

    Solid phase micro-extraction (SPME) coupled with Gas Chromatography Mass Spectrometry (GC-MS) was used to extract and analyse the volatiles in the headspace above the plasmodial and sporulating stages of the slime mould Physarum Polycephalum. In total 115 compounds were identified from across a broad range of chemical classes. Although more (87) volatile organic compounds (VOCs) were identified when using a higher incubation temperature of 75oC, a large number of compounds (79) were still ide...

  3. Headspace-SPME-GC/MS as a simple cleanup tool for sensitive 2,6-diisopropylphenol analysis from lipid emulsions and adaptable to other matrices.

    Science.gov (United States)

    Pickl, Karin E; Adamek, Viktor; Gorges, Roland; Sinner, Frank M

    2011-07-15

    Due to increased regulatory requirements, the interaction of active pharmaceutical ingredients with various surfaces and solutions during production and storage is gaining interest in the pharmaceutical research field, in particular with respect to development of new formulations, new packaging material and the evaluation of cleaning processes. Experimental adsorption/absorption studies as well as the study of cleaning processes require sophisticated analytical methods with high sensitivity for the drug of interest. In the case of 2,6-diisopropylphenol - a small lipophilic drug which is typically formulated as lipid emulsion for intravenous injection - a highly sensitive method in the concentration range of μg/l suitable to be applied to a variety of different sample matrices including lipid emulsions is needed. We hereby present a headspace-solid phase microextraction (HS-SPME) approach as a simple cleanup procedure for sensitive 2,6-diisopropylphenol quantification from diverse matrices choosing a lipid emulsion as the most challenging matrix with regard to complexity. By combining the simple and straight forward HS-SPME sample pretreatment with an optimized GC-MS quantification method a robust and sensitive method for 2,6-diisopropylphenol was developed. This method shows excellent sensitivity in the low μg/l concentration range (5-200μg/l), good accuracy (94.8-98.8%) and precision (intraday-precision 0.1-9.2%, inter-day precision 2.0-7.7%). The method can be easily adapted to other, less complex, matrices such as water or swab extracts. Hence, the presented method holds the potential to serve as a single and simple analytical procedure for 2,6-diisopropylphenol analysis in various types of samples such as required in, e.g. adsorption/absorption studies which typically deal with a variety of different surfaces (steel, plastic, glass, etc.) and solutions/matrices including lipid emulsions. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Tequila authenticity assessment by headspace SPME-HRGC-IRMS analysis of 13C/12C and 18O/16O ratios of ethanol.

    Science.gov (United States)

    Aguilar-Cisneros, Blanca O; López, Mercedes G; Richling, Elke; Heckel, Frank; Schreier, Peter

    2002-12-18

    By use of headspace SPME sampling and a PLOT column, on-line capillary gas chromatography-isotope ratio mass spectrometry was employed in the combustion (C) and the pyrolysis (P) modes (HRGC-C/P-IRMS) to determine the delta(13)C(VPDB) and delta(18)O(VSMOW) values of ethanol in authentic (n = 14) and commercial tequila samples (n = 15) as well as a number of other spirits (n = 23). Whereas with delta(13)C(VPDB) values ranging from -12.1 to -13.2 per thousand and from -12.5 to -14.8 per thousand similar variations were found for 100% agave and mixed tequilas, respectively, the delta(18)O(VSMOW) data differed slightly within these categories: ranges from +22.1 to +22.8 per thousand and +20.8 to +21.7 per thousand were determined for both the authentic 100% agave and mixed products, respectively. The data recorded for commercial tequilas were less homogeneous; delta(13)C(VPDB) data from -10.6 to -13.9 per thousand and delta(18)O(VSMOW) values from +15.5 to +22.7 per thousand were determined in tequilas of both categories. Owing to overlapping data, attempts to differentiate between white, rested, and aged tequilas within each of the two categories failed. In addition, discrimination of tequila samples from other spirits by means of delta(13)C(VPDB) and delta(18)O(VSMOW) data of ethanol was restricted to the products originating from C(3) as well as C(4)/CAM raw materials.

  5. Screening for γ-Nonalactone in the Headspace of Freshly Cooked Non-Scented Rice Using SPME/GC-O and SPME/GC-MS

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    Jie Yu Chen

    2009-08-01

    Full Text Available The determination of γ-nonalactone as one of the important odor-active compounds in freshly cooked non-scented rice is reported. It was evaluated by gas chromatography-olfactometry (GC-O analysis and identified by gas chromatography-mass spectrometry (GC-MS analysis in the headspace above the freshly cooked non-scented rice samples extracted by using a modified headspace solid-phase microextraction (SPME method. This component had a mass spectrum with a characteristic ion peak at m/z 85 (100% and a linear retention index (RI of 2,023 on a DB Wax column, consistent with those of an authentic sample of γ-nonalactone. The odor characterization of a strong, sweet, coconut-like aroma of this compound was also validated by GC-O comparison with the authentic compound.

  6. Use of headspace SPME-GC-MS for the analysis of the volatiles produced by indoor molds grown on different substrates.

    Science.gov (United States)

    Van Lancker, Fien; Adams, An; Delmulle, Barbara; De Saeger, Sarah; Moretti, Antonio; Van Peteghem, Carlos; De Kimpe, Norbert

    2008-10-01

    An automated headspace solid phase microextraction method followed by GC-MS analysis was used to evaluate and compare the in vitro production of microbial volatile organic compounds (MVOCs) on malt extract agar, plasterboard and wallpaper. Five fungal strains were isolated from the walls of water-damaged houses and identified. In addition, four other common molds were studied. In general, MVOC production was the highest on malt extract agar. On this synthetic medium, molds typically produced 2-methylpropanol, 2-methylbutanol and 3-methylbutanol. On wallpaper, mainly 2-ethylhexanol, methyl 2-ethylhexanoate and compounds of the C8-complex such as 1-octene-3-ol, 3-octanone, 3-octanol and 1,3-octadiene were detected. The detection of 2-ethylhexanol and methyl 2-ethylhexanoate indicates an enhanced degradation of the substrate by most fungi. For growth on plasterboard, no typical metabolites were detected. Despite these metabolite differences on malt extract agar, wallpaper and plasterboard, some molds also produced specific compounds independently of the used substrate, such as trichodiene from Fusarium sporotrichioides and aristolochene from Penicillium roqueforti. Therefore, these metabolites can be used as markers for the identification and maybe also mycotoxin production of these molds. All five investigated Penicillium spp. in this study were able to produce two specific diterpenes, which were not produced by the other species studied. These two compounds, which remain unidentified until now, therefore seem specific for Penicillium spp. and are potentially interesting for the monitoring of this fungal genus. Further experiments will be performed with other Penicillium spp. to study the possibility that these two compounds are specific for this group of molds.

  7. Determination of tetrachloroethylene and other volatile halogenated organic compounds in oil wastes by headspace SPME GC-MS

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, D.; Bezzi, R.; Torri, C.; Galletti, P.; Tagliavini, E. [Bologna Univ., Ravenna (Italy). Lab. of Chemistry, C.I.R.S.A

    2007-09-15

    Oil wastes and slops are complex mixtures of hydrocarbons, which may contain a variety of contaminants including tetrachloroethylene (perchloroethylene, PCE) and other volatile halogenated organic compounds (VHOCs). The analytical determination of PCE at trace levels in petroleum-derived matrices is difficult to carry out in the presence of large amounts of hydrocarbon matrix components. In the following study, we demonstrate that headspace solid-phase microextraction (HS-SPME) combined with GC-MS analysis can be applied for the rapid measurement of PCE concentration in oil samples. The HS-SPME method was developed using liquid paraffin as matrix matching reference material for external and internal calibration and optimisation of experimental parameters. The limit of quantitation was 0.05 mg kg{sup -1}, and linearity was established up to 25 mg kg{sup -1}. The HS-SPME method was extended to several VHOCs, including trichloroethylene (TCE) in different matrices and was applied to the quantitative analysis of PCE and TCE in real samples.

  8. Phytoscreening with SPME: Variability Analysis.

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    Limmer, Matt A; Burken, Joel G

    2015-01-01

    Phytoscreening has been demonstrated at a variety of sites over the past 15 years as a low-impact, sustainable tool in delineation of shallow groundwater contaminated with chlorinated solvents. Collection of tree cores is rapid and straightforward, but low concentrations in tree tissues requires sensitive analytics. Solid-phase microextraction (SPME) is amenable to the complex matrix while allowing for solvent-less extraction. Accurate quantification requires the absence of competitive sorption, examined here both in laboratory experiments and through comprehensive examination of field data. Analysis of approximately 2,000 trees at numerous field sites also allowed testing of the tree genus and diameter effects on measured tree contaminant concentrations. Collectively, while these variables were found to significantly affect site-adjusted perchloroethylene (PCE) concentrations, the explanatory power of these effects was small (adjusted R(2) = 0.031). 90th quantile chemical concentrations in trees were significantly reduced by increasing Henry's constant and increasing hydrophobicity. Analysis of replicate tree core data showed no correlation between replicate relative standard deviation (RSD) and wood type or tree diameter, with an overall median RSD of 30%. Collectively, these findings indicate SPME is an appropriate technique for sampling and analyzing chlorinated solvents in wood and that phytoscreening is robust against changes in tree type and diameter.

  9. Determination of organotin compounds by headspace solid-phase microextraction-gas chromatography-pulsed flame-photometric detection (HS-SPME-GC-PFPD)

    Energy Technology Data Exchange (ETDEWEB)

    Bravo, Manuel [Universite de Pau et des Pays de L' Adour, Laboratoire de Chimie Analytique, LCABIE, UMR CNRS 5034, Pau (France); Pontificia Universidad Catolica de Valparaiso, Laboratorio de Quimica Analitica y Ambiental, Instituto de Quimica, Valparaiso (Chile); Lespes, Gaetane; Gautier, Martine Potin [Pontificia Universidad Catolica de Valparaiso, Laboratorio de Quimica Analitica y Ambiental, Instituto de Quimica, Valparaiso (Chile); Gregori, Ida de; Pinochet, Hugo [Universite de Pau et des Pays de L' Adour, Laboratoire de Chimie Analytique, LCABIE, UMR CNRS 5034, Pau (France)

    2005-12-01

    A method based on Headspace solid-phase microextraction (HS-SPME, with a 100 {mu}m PDMS-fiber) in combination with gas-chromatography and pulsed flame-photometric detection (GC-PFPD) has been investigated for simultaneous determination of eight organotin compounds. Monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), monophenyltin (MPhT), and the semi-volatile diphenyltin (DPhT), triphenyltin (TPhT), monooctyltin (MOcT), and dioctyltin (DOcT) were determined after derivatization with sodium tetraethylborate. The conditions used for the extraction and preconcentration step were optimised by experimental design methodology. Tripropyltin (TPrT) and diheptyltin (DHepT) were used as internal standards for quantification of volatile and semi-volatile organotin compounds, respectively. The analytical precision (RSD) for ten successive injections of a standard mixture containing all the organic tin compounds ranged between 2 and 11%. The limits of detection for all the organotin compounds were sub ng (Sn) L{sup -1} in water and close to ng (Sn) kg{sup -1} in sediments. The accuracy of the method was evaluated by analysis of two certified reference material (CRM) sediment samples. The HS-SPME-GC-PFPD was then applied to the analysis of three harbour sediment samples. The results showed that headspace SPME is an attractive tool for analysis of organotin compounds in solid environmental matrices. (orig.)

  10. A screening method for polycyclic aromatic hydrocarbons determination in water by headspace SPME with GC-FID

    Energy Technology Data Exchange (ETDEWEB)

    Zuazagoitia, D.; Millan, E.; Garcia, R. [Univ. of Pais Vasco, Donostia-San Sebastian (Spain). Dept. of Applied Chemistry

    2007-11-15

    A simple method for determination of polycyclic aromatic hydrocarbons (PAHs) in water using headspace solid-phase microextraction (HS-SPME) with gas chromatography-flame ionisation detector (GC-FID) was developed. In order to obtain the convenient experimental conditions for HS-SPME extraction an experimental design with two steps was accomplished. A 2{sup 6-2} fractional factorial design and central composite design (CCD) considering three significant factors were used. Naphthalene, anthracene and fluoranthene were chosen as representatives of two, three and four aromatic rings, and the global response of three PAHs was used for the results, evaluation. The chosen extraction conditions were: 85 {mu}m polyacrylate fibre; 50 C temperature; 60 min time; 20 mL-dissolution volume (in 40 mL glass vial); without salt addition; and 2 min desorption time. The procedure was extended to other seven PAHs (acenaphthylene, acenaphthene, fluorene, phenanthrene, pyrene, chrysene and benzo(a)anthracene) and the analytical characteristics were checked. The limit of detection (LOD) was from 0.08 (anthracene) to 0.20 {mu}g L{sup -1} (naphthalene). The precision expressed as relative standard deviation (RSD in %) using 50 {mu}g L{sup -1} of each analyte ranged from 6.8 to 17 %. The method was applied to the analysis of the surface waters and leaching waters of contaminated soils from Gipuzkoa (North Spain). The PAHs were not detected in surface water samples. Most of the PAHs were found in the leachates from contaminated soils showing a maximum global value of 75.5 {mu}g L{sup -1}. (orig.)

  11. A Headspace Solid Phase Microextraction (HS-SPME method for the chromatographic determination of alkylpyrazines in cocoa samples

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    Pini Gláucia F.

    2004-01-01

    Full Text Available A Headspace Solid Phase Microextraction (HS-SPME procedure for isolation and determination of alkylpyrazines in cocoa liquor, using Gas Chromatography with Flame Ionization Detection (GC-FID for the separation and detection of the analytes, is presented here. The HS-SPME operational conditions were optimized using extractions of samples spiked with known amounts of alkylpyrazines typically found on cocoa products. The maximum extraction efficiency was obtained using SPME fibers coated with 65 µm Carbowax/divinylbenzene. Additionally, the best results were achieved with extraction temperature of 60 ºC, 15 min of sample/headspace equilibration time and 45 min extraction time. It was also observed that suspending the samples in saturated aqueous NaCl solution during extractions resulted in a significant increment on the peak areas. This procedure was found to be effective to determine the so-called pyrazinic ratios (quotient between peak areas of alkylpyrazines, which are useful as quality parameters for cocoa liquor.

  12. Differentiation of Toxic Molds via Headspace SPME-GC/MS and Canine Detection

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    Kenneth G. Furton

    2007-08-01

    Full Text Available Indoor mold growth has recently become a concern in the legal world in regards to insurance litigation. Hazardous mold exposure to humans has been linked to many acute and chronic adverse health effects including death. As it grows, mold produces several types of primary and secondary metabolites, including microbial volatile organic compounds (MVOCs. Microbial volatile organic compound emission may be used as a preliminary indication of a mold infestation that is invisible to the unaided eye. The objective of the study is to identify the unique odor signatures of three species of molds, Aspergillus versicolor, Penicillium chrysogenum, and Stachybotrys chartarum by SPME-GC/MS analysis. Determining the compounds that are emitted by the selected species has made it possible to conduct validation studies of canine detection of these mold species through a series of field tests.

  13. Approaches of aroma extraction dilution analysis (AEDA) for headspace solid phase microextraction and gas chromatography-olfactometry (HS-SPME-GC-O): Altering sample amount, diluting the sample or adjusting split ratio?

    Science.gov (United States)

    Feng, Yunzi; Cai, Yu; Sun-Waterhouse, Dongxiao; Cui, Chun; Su, Guowan; Lin, Lianzhu; Zhao, Mouming

    2015-11-15

    Aroma extract dilution analysis (AEDA) is widely used for the screening of aroma-active compounds in gas chromatography-olfactometry (GC-O). In this study, three aroma dilution methods, (I) using different test sample volumes, (II) diluting samples, and (III) adjusting the GC injector split ratio, were compared for the analysis of volatiles by using HS-SPME-AEDA. Results showed that adjusting the GC injector split ratio (III) was the most desirable approach, based on the linearity relationships between Ln (normalised peak area) and Ln (normalised flavour dilution factors). Thereafter this dilution method was applied in the analysis of aroma-active compounds in Japanese soy sauce and 36 key odorants were found in this study. The most intense aroma-active components in Japanese soy sauce were: ethyl 2-methylpropanoate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl 4-methylpentanoate, 3-(methylthio)propanal, 1-octen-3-ol, 2-methoxyphenol, 4-ethyl-2-methoxyphenol, 2-methoxy-4-vinylphenol, 2-phenylethanol, and 4-hydroxy-5-ethyl-2-methyl-3(2H)-furanone. Copyright © 2015. Published by Elsevier Ltd.

  14. Authentication of pineapple (Ananas comosus [L.] Merr.) fruit maturity stages by quantitative analysis of γ- and δ-lactones using headspace solid-phase microextraction and chirospecific gas chromatography-selected ion monitoring mass spectrometry (HS-SPME-GC-SIM-MS).

    Science.gov (United States)

    Steingass, Christof B; Langen, Johannes; Carle, Reinhold; Schmarr, Hans-Georg

    2015-02-01

    Headspace solid phase microextraction and chirospecific gas chromatography-mass spectrometry in selected ion monitoring mode (HS-SPME-GC-SIM-MS) allowed quantitative determination of δ-lactones (δ-C8, δ-C10) and γ-lactones (γ-C6, γ-C8, γ-C10). A stable isotope dilution assay (SIDA) with d7-γ-decalactone as internal standard was used for quantitative analysis of pineapple lactones that was performed at three progressing post-harvest stages of fully ripe air-freighted and green-ripe sea-freighted fruits, covering the relevant shelf-life of the fruits. Fresh pineapples harvested at full maturity were characterised by γ-C6 of high enantiomeric purity remaining stable during the whole post-harvest period. In contrast, the enantiomeric purity of γ-C6 significantly decreased during post-harvest storage of sea-freighted pineapples. The biogenetical background and the potential of chirospecific analysis of lactones for authentication and quality evaluation of fresh pineapple fruits are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Screening of transformation products in soils contaminated with unsymmetrical dimethylhydrazine using headspace SPME and GC-MS

    NARCIS (Netherlands)

    Kenessov, B.N.; Koziel, J.A.; Grotenhuis, J.T.C.; Carlsen, L.

    2010-01-01

    The paper describes a novel SPME-based approach for sampling and analysis of transformation products of highly reactive and toxic unsymmetrical dimethylhydrazine (UDMH) which is used as a fuel in many Russian, European, Indian, and Chinese heavy cargo carrier rockets. The effects of several

  16. Application of head-space solid-phase microextraction for the analysis of volatile metabolites emitted by Penicillium species

    DEFF Research Database (Denmark)

    Nilsson, Torben; Larsen, Thomas Ostenfeld; Montanarella, Luca

    1996-01-01

    Head-space solid-phase microextraction (HS-SPME) has been used to collect volatile organic compounds (VOCs) emitted from fungi of the genus Penicillium. Gas chromatography combined with mass spectrometry (GC-MS) was employed for the analysis of the profiles of volatile metabolites characteristic...

  17. Headspace solid-phase microextraction (HS-SPME) and liquid-liquid extraction (LLE): comparison of the performance in classification of ecstasy tablets. Part 2.

    Science.gov (United States)

    Bonadio, Federica; Margot, Pierre; Delémont, Olivier; Esseiva, Pierre

    2008-11-20

    Headspace solid-phase microextraction (HS-SPME) is assessed as an alternative to liquid-liquid extraction (LLE) currently used for 3,4-methylenedioxymethampethamine (MDMA) profiling. Both methods were compared evaluating their performance in discriminating and classifying samples. For this purpose 62 different seizures were analysed using both extraction techniques followed by gas chromatography-mass spectroscopy (GC-MS). A previously validated method provided data for HS-SPME, whereas LLE data were collected applying a harmonized methodology developed and used in the European project CHAMP. After suitable pre-treatment, similarities between sample pairs were studied using the Pearson correlation. Both methods enable to distinguish between samples coming from the same pre-tabletting batches and samples coming from different pre-tabletting batches. This finding emphasizes the use of HS-SPME as an effective alternative to LLE, with additional advantages such as sample preparation and a solvent-free process.

  18. Otimização e validação de métodos analíticos para determinação de BTEX em água utilizando extração por headspace e microextração em fase sólida Evaluation of analytical methods for BTEX analysis in water using extraction by headspace (HS and solid phase microextraction (SPME

    Directory of Open Access Journals (Sweden)

    Fernanda F. Heleno

    2010-01-01

    Full Text Available Three analytical methods for the determination of BTEX in water were optimized and validated. With the best method the analytes were extracted of 10 mL of sample with 2.50 g of NaCl in headspace vial of 20 mL by HS and SPME to 40 ºC for 30 min for adsorption and to 250 ºC for 4 min for desorption and were analyzed by GC-MS. The recovery was between 97.9% and 104.3%, and the limit of detection was 2.4 ng L-1 for o-xylene. This method was using to analyze BTEX in water supply and surface water in Ouro Preto city. No sample had concentrations of BTEX above the legislation.

  19. Headspace solid-phase microextraction procedures for gas chromatographic analysis of biological fluids and materials.

    Science.gov (United States)

    Mills, G A; Walker, V

    2000-12-01

    Solid-phase microextraction (SPME) is a new solventless sample preparation technique that is finding wide usage. This review provides updated information on headspace SPME with gas chromatographic separation for the extraction and measurement of volatile and semivolatile analytes in biological fluids and materials. Firstly the background to the technique is given in terms of apparatus, fibres used, extraction conditions and derivatisation procedures. Then the different matrices, urine, blood, faeces, breast milk, hair, breath and saliva are considered separately. For each, methods appropriate for the analysis of drugs and metabolites, solvents and chemicals, anaesthetics, pesticides, organometallics and endogenous compounds are reviewed and the main experimental conditions outlined with specific examples. Then finally, the future potential of SPME for the analysis of biological samples in terms of the development of new devices and fibre chemistries and its coupling with high-performance liquid chromatography is discussed.

  20. Comparative analysis of the aroma chemicals of Melissa officinalis using hydrodistillation and HS-SPME techniques

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    Shakeel-u- Rehman

    2017-05-01

    Full Text Available Headspace solid-phase micro extraction (HS-SPME coupled with gas chromatography–mass spectrometry (GC–MS has been used for the chemical analysis of Melissa officinalis (leaves cultivated in Institute Germplasm. The HS-SPME analysis led to the identification of 22 components constituting 99.1% of the total volatile constituents present in the leaves whereas its hydrodistillate led to the identification of 24 volatile constituents constituting 98.1% of the volatile material. The chemical composition of the SPME and hydrodistilled extract of M. officinalis leaves comprised mainly of oxygenated monoterpenes (78.5% and 57.8% respectively and sesquiterpene hydrocarbons (14.9% and 29.7% respectively. The major components identified in the HS-SPME extract were citronellal (31.1%, citronellol (18.3%, β-caryophyllene (12.0%, (E-citral (11.9%, (Z-citral (9.6%, geraniol (3.6%, (Z-β-ocimene (3.1% and 1-octen-3-ol (2.0% whereas hydrodistilled essential oil was rich in (Z-citral (19.6%, β-caryophyllene (13.2%, (E-citral (11.2%, citronellal (10.2%, germacrene-d (8.3%, δ-3-carene (5.0%, 6-methyl-5-hepten-2-one (3.7% and citronellyl acetate (3.7%. The comparative analysis of volatile constituents of M. officinalis leaf extract using HS-SPME and hydrodistillation techniques shows both qualitative as well as quantitative differences. The current study is the first report involving rapid analysis of volatile components of M. officinalis by HS-SPME.

  1. Headspace Analysis of Ammonium Nitrate

    Science.gov (United States)

    2017-01-25

    explosive ammonium nitrate produces ammonia and nitric acid in the gaseous headspace above bulk solids, but the concentrations of the products have been...and NO2-, a product of nitrate fragmentation (Figure 7). Brief spikes in the background and dips in oxalic acid signal were observed at the time of...either filtered air or experimental nitric acid vapor sources so that analyte signal could be measured directly opposite background. With oxalic

  2. Determination of Selected Aromas in Marquette and Frontenac Wine Using Headspace-SPME Coupled with GC-MS and Simultaneous Olfactometry

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    Somchai Rice

    2018-03-01

    Full Text Available Understanding the aroma profile of wines made from cold climate grapes is needed to help winemakers produce quality aromatic wines. The current study aimed to add to the very limited knowledge of aroma-imparting compounds in wines made from the lesser-known Frontenac and Marquette cultivars. Headspace solid-phase microextraction (SPME and gas chromatography-mass spectrometry (GC-MS with simultaneous olfactometry was used to identify and quantify selected, aroma-imparting volatile organic compounds (VOC in wines made from grapes harvested at two sugar levels (22° Brix and 24° Brix. Aroma-imparting compounds were determined by aroma dilution analysis (ADA. Odor activity values (OAV were also used to aid the selection of aroma-imparting compounds. Principal component analysis and hierarchical clustering analysis indicated that VOCs in wines produced from both sugar levels of Marquette grapes are similar to each other, and more similar to wines produced from Frontenac grapes harvested at 24° Brix. Selected key aroma compounds in Frontenac and Marquette wines were ethyl hexanoate, ethyl isobutyrate, ethyl octanoate, and ethyl butyrate. OAVs >1000 were reported for three aroma compounds that impart fruity aromas to the wines. This study provides evidence that aroma profiles in Frontenac wines can be influenced by timing of harvesting the berries at different Brix. Future research should focus on whether this is because of berry development or accumulation of aroma precursors and sugar due to late summer dehydration. Simultaneous chemical and sensory analyses can be useful for the understanding development of aroma profile perceptions for wines produced from cold-climate grapes.

  3. Quantitative analysis of perfumes in talcum powder by using headspace sorptive extraction.

    Science.gov (United States)

    Ng, Khim Hui; Heng, Audrey; Osborne, Murray

    2012-03-01

    Quantitative analysis of perfume dosage in talcum powder has been a challenge due to interference of the matrix and has so far not been widely reported. In this study, headspace sorptive extraction (HSSE) was validated as a solventless sample preparation method for the extraction and enrichment of perfume raw materials from talcum powder. Sample enrichment is performed on a thick film of poly(dimethylsiloxane) (PDMS) coated onto a magnetic stir bar incorporated in a glass jacket. Sampling is done by placing the PDMS stir bar in the headspace vial by using a holder. The stir bar is then thermally desorbed online with capillary gas chromatography-mass spectrometry. The HSSE method is based on the same principles as headspace solid-phase microextraction (HS-SPME). Nevertheless, a relatively larger amount of extracting phase is coated on the stir bar as compared to SPME. Sample amount and extraction time were optimized in this study. The method has shown good repeatability (with relative standard deviation no higher than 12.5%) and excellent linearity with correlation coefficients above 0.99 for all analytes. The method was also successfully applied in the quantitative analysis of talcum powder spiked with perfume at different dosages. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Determination of different recreational drugs in sweat by headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME GC/MS): Application to drugged drivers.

    Science.gov (United States)

    Gentili, Stefano; Mortali, Claudia; Mastrobattista, Luisa; Berretta, Paolo; Zaami, Simona

    2016-09-10

    A procedure based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometry (GC/MS) has been developed for the determination of most commonly used drugs of abuse in sweat of drivers stopped during roadside controls. DrugWipe 5A sweat screening device was used to collect sweat by a specific pad rubbed gently over forehead skin surface. The procedure involved an acid hydrolysis, a HS-SPME extraction for drugs of abuse but Δ(9)-tetrahydrocannabinol, which was directly extracted in alkaline medium HS-SPME conditions, a GC separation of analytes by a capillary column and MS detection by electron impact ionisation. The method was linear from the limit of quantification (LOQ) to 50ng drug per pad (r(2)≥0.99), with an intra- and inter-assay precision and accuracy always less than 15% and an analytical recovery between 95.1% and 102.8%, depending on the considered analyte. Using the validated method, sweat from 60 apparently intoxicated drivers were found positive to one or more drugs of abuse, showing sweat patches testing as a viable economic and simple alternative to conventional (blood and/or urine) and non conventional (oral fluid) testing of drugs of abuse in drugged drivers. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Analysis of Volatile Compounds from Solanumbetaceum Cav. Fruits from Panama by Head-Space Micro Extraction

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    Armando A. Durant

    2013-01-01

    Full Text Available The characterization of the volatile compounds of two varieties of Solanum betaceum Cav. by means of headspace solid-phase microextraction (HS-SPME coupled with gas chromatography-mass spectrometry ( GC-MS i s presented. The HS-SPME method for extraction of the volatiles compounds was optimized by using a 2 3 central composite design. Maximum extraction of volatile compounds was achieved by using a divinylbenzene-carboxen-polydimethylsiloxane (DVB/CAR/PDMS fiber, extraction temperature 76° C, incubation time 44 min, and extraction time of 46 min. The main types of compounds detected in both varieties are terpenoids, followed by aromatics, esters, and aldehydes. Golden-yellow cultivars contained higher levels of esters and terpenes, while the reddish-purple variety contained a significant amount of aromatic compounds. The data structure of the chemical information obtained as well as the relationship between variables was evaluated by means of principal component analysis and cluster analysis.

  6. Is Solid Phase Microextraction (SPME) an appropriate method for extraction of volatile oxidation products from complex food systems

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Horn, Anna Frisenfeldt; Lu, Henna Fung Sieng

    Volatile secondary lipid oxidation products can be identified and quantified by GC-FID or GC-MS. An extraction step is, however, needed before GC analysis. A range of different extraction methods are available such as static headspace, dynamic headspace and SPME. Each of these methods has its...... advantages and drawbacks. Among the advantages of the SPME method are its high sensitivity compared to static headspace and that it is less laborious than the dynamic headspace method. For these reasons, the use of SPME has increased in both academia and industry during the last decade. The extraction...... for analysis of lipid oxidation during storage of complex food matrices. Examples on how uncontrollable factors have affected results obtained with the SPME method in the authors’ lab will be given and the appropriateness of the SPME method for the analysis of volatile oxidation products in selected food...

  7. Solid phase microextraction (SPME) for extraction of volatile oxidation products from complex food systems – Pros and cons

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Horn, Anna Frisenfeldt; Lu, Henna Fung Sieng

    Volatile secondary lipid oxidation products can be identified and quantified by GC-FID or GC-MS. An extraction step is, however, needed before GC analysis. A range of different extraction methods are available such as static headspace, dynamic headspace and SPME. Each of these methods has its...... advantages and drawbacks. Among the advantages of the SPME method are its high sensitivity compared to static headspace and that it is less laborious than the dynamic headspace method. For these reasons, the use of SPME has increased in both academia and industry during the last decade. The extraction...... for analysis of lipid oxidation during storage of complex food matrices. Examples on how uncontrollable factors have affected results obtained with the SPME method in the authors’ lab will be given and the appropriateness of the SPME method for the analysis of volatile oxidation products in selected food...

  8. Headspace solid-phase microextraction (HS-SPME) combined with GC-MS as a process analytical technology (PAT) tool for monitoring the cultivation of C. tetani.

    Science.gov (United States)

    Ghader, Masoud; Shokoufi, Nader; Es-Haghi, Ali; Kargosha, Kazem

    2018-04-15

    Vaccine production is a biological process in which variation in time and output is inevitable. Thus, the application of Process Analytical Technologies (PAT) will be important in this regard. Headspace solid - phase microextraction (HS-SPME) coupled with GC-MS can be used as a PAT for process monitoring. This method is suitable to chemical profiling of volatile organic compounds (VOCs) emitted from microorganisms. Tetanus is a lethal disease caused by Clostridium tetani (C. tetani) bacterium and vaccination is an ultimate way to prevent this disease. In this paper, SPME fiber was used for the investigation of VOCs emerging from C. tetani during cultivation. Different types of VOCs such as sulfur-containing compounds were identified and some of them were selected as biomarkers for bioreactor monitoring during vaccine production. In the second step, the portable dynamic air sampling (PDAS) device was used as an interface for sampling VOCs by SPME fibers. The sampling procedure was optimized by face-centered central composite design (FC-CCD). The optimized sampling time and inlet gas flow rates were 10 min and 2 m L s -1 , respectively. PDAS was mounted in exhausted gas line of bioreactor and 42 samples of VOCs were prepared by SPME fibers in 7 days during incubation. Simultaneously, pH and optical density (OD) were evaluated to cultivation process which showed good correlations with the identified VOCs (>80%). This method could be used for VOCs sampling from off-gas of a bioreactor to monitoring of the cultivation process. Copyright © 2018. Published by Elsevier B.V.

  9. A home-made SPME fiber coating for Arson Analysis

    International Nuclear Information System (INIS)

    Umi Khairul Ahmad; Abdul Rahim Yacob; Selvaraju, Geetha

    2008-01-01

    A number of adsorbents are available commercially as coatings for SPME fibers but some analytical methodologies might demand specific properties for the extraction of selected compounds, special coatings that have particular volume and a selectivity towards particular analytes. This paper presents a simple, fast, effective and environmental friendly methodology for the determination of accelerants in arson samples using headspace solid-phase micro extraction coupled to gas chromatography. A new fiber prepared by sol-gel method, containing 1:1 molar ratio of octyltriethoxysilane (C 8 -TEOS): methyltrimethoxysilane (MTMOS) was employed in this technique. The efficiency of the new fiber coating prepared by sol-gel technology for the determination of accelerants was compared to that of commercial PDMS/ DVB fibers. Poly dimethylsiloxane divinylbenzene (PDMS/ DVB) is the most common fiber coating for the extraction of hydrocarbon compounds. Compared with commercial PDMS/ DVB fiber, the new homemade fiber exhibited higher extraction capability and good selectivity for accelerants. The homemade fiber was also applied for the simulated arson samples. The home-made SPME adsorbent was shown to be a good alternative to commercially available fiber for the determination of accelerants in arson cases. (author)

  10. The Use of Headspace Solid-Phase Microextraction (HS-SPME to Assess the Quality and Stability of Fruit Products: An Example Using Red Mombin Pulp (Spondias purpurea L.

    Directory of Open Access Journals (Sweden)

    Katieli Martins Todisco

    2014-10-01

    Full Text Available The present study aimed to evaluate the volatiles profile of red mombin (Spondias purpurea pulp and its powder produced by spray-drying (SD as an example to show utility of headspace solid-phase microextraction (HS-SPME in the analysis of parameters such as the quality and stability of fruit products. Volatiles profiles of the pulp were identified by gas chromatography-mass spectrometry (GC-MS, quantified by gas chromatography-flame ionization detector (GC-FID and compared to the profile of the powder stored at 0, 60 and 120 days in plastic (PP or laminated packages (LP. The results showed that the technique was able to identify 36 compounds in the red mombin pulp, 17 out of which have been described for the first time in this fruit, showing that red mombin fresh pulp appears to be unique in terms of volatiles composition. However, only 24 compounds were detected in the powder. This decrease is highly correlated (r2 = 0.99, at least for the majority of compounds, to the degree of volatility of compounds. Furthermore, the powder stored in PP or LP showed no statistical differences in the amounts of its components for a period of 120 days of storage. Finally, this work shows how HS-SPME analysis can be a valuable tool to assess the quality and stability of fruit products.

  11. HS-SPME-GC-MS ANALYSIS OF VOLATILE AND SEMI-VOLATILE COMPOUNDS FROM DRIED LEAVES OF Mikania glomerata Sprengel

    Directory of Open Access Journals (Sweden)

    Esmeraldo A. Cappelaro

    2015-03-01

    Full Text Available This paper reports on the identification of volatile and semi-volatile compounds and a comparison of the chromatographic profiles obtained by Headspace Solid-Phase Microextraction/Gas Chromatography with Mass Spectrometry detection (HS-SPME-GC-MS of dried leaves of Mikania glomerata Sprengel (Asteraceae, also known as 'guaco.' Three different types of commercial SPME fibers were tested: polydimethylsiloxane (PDMS, polydimethylsiloxane/divinylbenzene (PDMS/DVB and polyacrylate (PA. Fifty-nine compounds were fully identified by HS-SPME-HRGC-MS, including coumarin, a marker for the quality control of guaco-based phytomedicines; most of the other identified compounds were mono- and sesquiterpenes. PA fibers performed better in the analysis of coumarin, while PDMS-DVB proved to be the best choice for a general and non-selective analysis of volatile and semi-volatile guaco-based compounds. The SPME method is faster and requires a smaller sample than conventional hydrodistillation of essential oils, providing a general overview of the volatile and semi-volatile compounds of M. glomerata.

  12. Analysis of organic micropollutants in drinking water using SPME and GC-MS

    International Nuclear Information System (INIS)

    Guidotti, M.; Ravaioli, G.

    1999-01-01

    In this work the purpose was to develop accurate and reproducible methods for the qualitative and quantitative analysis of pesticides/herbicides, phthalates, chlorinated solvents, trihalomethanes, polycyclic aromatic hydrocarbons (PAHs) and chlorophenols in drinking waters, using solid-phase micro extraction and GC-MS techniques. The SPME developed by J. Pawliszyn and co-workers, consists of an fused silica fibre, coated with an appropriate absorbent phase, hosted inside the needle of a holder that looks like a GC-syringe; the needle pierces the septum of a sealed vial and the fibre is lowered, by depressing the plunger of the holder, into the liquid (or in the headspace, if that is the case) that contains the analytes of interest. After a set period of time, necessary to reach the partitioning equilibrium, the fibre is retracted inside the needle, the needle is inserted into the GC injector port and the fibre pushed in the heated injector. Here the compounds of interest (that have adsorbed onto the fibre) are thermally desorbed and analysed by GC-MS. After three minutes the fibre is extracted and is ready for a new analysis. The SPME technique has already found many applications in food and environmental analysis. Many of the analytes investigated in this research are listed Italian legislation as possible pollutants of drinking waters and their presence and concentrations require monitoring. The list of compounds included in this work is reported in Table 1

  13. Volatiles and primary metabolites profiling in two Hibiscus sabdariffa (roselle) cultivars via headspace SPME-GC-MS and chemometrics.

    Science.gov (United States)

    Farag, Mohamed A; Rasheed, Dalia M; Kamal, Islam M

    2015-12-01

    Hibiscus sabdariffa (roselle) is a plant of considerable commercial importance worldwide as functional food due to its organic acids, mucilage, anthocyanins, macro and micro-nutrients content. Although Hibiscus flowers are emerging as very competitive targets for phytochemical studies, very little is known about their volatile composition and or aroma, such knowledge can be suspected to be relevant for understanding its olfactory and taste properties. To provide insight into Hibiscus flower aroma composition and for its future use in food and or pharmaceutical industry, volatile constituents from 2 cultivars grown in Egypt, viz. Aswan and Sudan-1 were profiled using solid-phase microextraction (SPME) coupled to GCMS. A total of 104 volatiles were identified with sugar and fatty acid derived volatiles amounting for the major volatile classes. To reveal for cultivar effect on volatile composition in an untargeted manner, multivariate data analysis was applied. Orthogonal projection to latent structures-discriminant analysis (OPLS-DA) revealed for 1-octen-3-ol versus furfural/acetic acid enrichment in Aswan and Sudan-1 cvs., respectively. Primary metabolites contributing to roselle taste and nutritional value viz. sugars and organic acids were profiled using GC-MS after silylation. The impact of probiotic bacteria on roselle infusion aroma profile was further assessed and revealed for the increase in furfural production with Lactobacillus plantarum inoculation and without affecting its anthocyanin content. This study provides the most complete map for volatiles, sugars and organic acids distribution in two Hibiscus flower cultivars and its fermented product. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Headspace sorptive solid phase microextraction (HS-SPME) combined with a spectrophotometry system: A simple glass devise for extraction and simultaneous determination of cyanide and thiocyanate in environmental and biological samples.

    Science.gov (United States)

    Al-Saidi, H M; Al-Harbi, Sami A; Aljuhani, E H; El-Shahawi, M S

    2016-10-01

    A simple, low cost and efficient headspace sorptive solid phase microextraction (HS-SPME) method for determination of cyanide has been developed. The system comprises of a glass tube with two valves and a moveable glass slide fixed at its centre. It includes an acceptor phase polyurethane foam treated mercury (II) dithizonate [Hg(HDz)2-PUF] complex fixed inside by a septum cap in a cylindrical configuration (5.0cm length and 1.0cm diameter). The extraction is based upon the contact of the acceptor phase to the headspace and subsequently measuring the absorbance of the recovered mercury (II) dithizonate from PUFs sorbent. Unlike other HSSE, extraction and back - extractions was carried out in a closed system, thereby improving the analytical performance by preventing the analyte loss. Under the optimized conditions, a linear calibration plot in the range of 1.0-50.0µmolL(-1) was achieved with limits of detection (LOD) and quantification (LOQ) of 0.34, 1.2µmolL(-1) CN(-), respectively. Simultaneous analysis of cyanide and thiocyanate in saliva was also performed with satisfactory recoveries. Copyright © 2016. Published by Elsevier B.V.

  15. Degradation product emission from historic and modern books by headspace SPME/GC-MS: evaluation of lipid oxidation and cellulose hydrolysis.

    Science.gov (United States)

    Clark, Andrew J; Calvillo, Jesse L; Roosa, Mark S; Green, David B; Ganske, Jane A

    2011-04-01

    Volatile organic compounds emitted from a several decade series of bound periodicals (1859-1939) printed on ground wood paper, as well as historical books dating from the 1500s to early 1800s made from cotton/linen rag, were studied using an improved headspace SPME/GC-MS method. The headspace over the naturally aging books, stored upright in glass chambers, was monitored over a 24-h period, enabling the identification of a wide range of organic compounds emanating from the whole of the book. The detection of particular straight chain aldehydes, as well as characteristic alcohols, alkenes and ketones is correlated with oxidative degradation of the C(18) fatty acid constituency of paper. The relative importance of hydrolytic and oxidative chemistry involved in paper aging in books published between 1560 and 1939 was examined by comparing the relative abundances of furfural (FUR) a known cellulose hydrolysis product, and straight chain aldehydes (SCA) produced from the oxidation of fatty acids in paper. The relative abundance of furfural is shown to increase across the 379-year publication time span. A comparison of relative SCA peak areas across the series of books examined reveals that SCA emission is more important in the cotton/linen rag books than in the ground wood books.

  16. Headspace analysis of foams and fixatives

    Energy Technology Data Exchange (ETDEWEB)

    Harper, Kyle [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Truong, Thanh-Tam [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Magwood, Leroy [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Peters, Brent [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nicholson, James [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-27

    In the process of decontaminating and decommissioning (D&D) older nuclear facilities, special precautions must be taken with removable or airborne contamination. One possible strategy utilizes foams and fixatives to affix these loose contaminants. Many foams and fixatives are already commercially available, either generically or sold specifically for D&D. However, due to a lack of revelant testing in a radioactive environment, additional verification is needed to confirm that these products not only affix contamination to their surfaces, but also will function in a D&D environment. Several significant safety factors, including flammability and worker safety, can be analyzed through the process of headspace analysis, a technique that analyzes the off gas formed before or during the curing process of the foam/fixative, usually using gas chromatography-mass spectrometry (GC-MS). This process focuses on the volatile components of a chemical, which move freely between the solid/liquid form within the sample and the gaseous form in the area above the sample (the headspace). Between possibly hot conditions in a D&D situation and heat created in a foaming reaction, the volatility of many chemicals can change, and thus different gasses can be released at different times throughout the reaction. This project focused on analysis of volatile chemicals involved in the process of using foams and fixatives to identify any potential hazardous or flammable compounds.

  17. Comparative Analyses of the Volatile Components of Citrus Aurantium L. Flowers Using Ultrasonic-Assisted Headspace SPME and Hydrodistillation Combined with GC-MS and Evaluation of their Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Akram Rahimi

    2014-12-01

    Full Text Available The volatile components of Citrus aurantium L. flowers were characterized by GC-MS with two different extraction techniques, hydrodistillation (HD and ultrasonic-assisted headspace solid phase microextraction (UA-HS-SPME. In the SPME method, the volatile components of the samples, irradiated by ultrasonic radiation, were collected on a polydimethyl siloxane (PDMS commercial fiber as well as some manually prepared nanoporous fibers from the samples headspace. To reach the better results, the extraction conditions were carefully optimized for the PDMS fiber. Under the optimized conditions (i.e. sonication time 15 min, extraction time 30 min and extraction temperature 55 ºC, 54 compounds were identified by the UA-HS-SPME-GC/MS method. The essential oil components of Citrus aurantium L. flower samples from two different regions of Iran and new and old samples from the same region were compared to one another. The major components identified for the samples with both the SPME and HD methods were linalool, linalyl acetate, limonene, β-myrcene, geranyl acetate, and neryl acetate, respectively. However, a substantial variation in the percentages of the components was identified for different samples and different extraction methods. The antimicrobial activities of the oil were also examined against six standard bacteria. There was some activity against Enterococcus fecalis, Escherichia coli, and Bacillus cereus, indicating important biological activities of the oil.

  18. Influence of harvest maturity and fruit logistics on pineapple (Ananas comosus [L.] Merr.) volatiles assessed by headspace solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC/MS).

    Science.gov (United States)

    Steingass, Christof B; Grauwet, Tara; Carle, Reinhold

    2014-05-01

    Profiling of volatiles from pineapple fruits was performed at four ripening stages using headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC/MS). In total, 142 volatiles were detected, of which 132 were identified. Multivariate data analysis was carried out to assess the effect of post-harvest storage on volatiles composition of green-ripe sea-freighted pineapple in comparison to air-freighted fruits harvested at full maturity. The latter fruits were characterised by volatiles described as potent odorants in pineapples, such as δ-octalactone, γ-lactones, 1-(E,Z)-3,5-undecatriene and 1,3,5,8-undecatetraene, as well as various methyl esters. In contrast, post-harvest storage of green-ripe sea-freighted fruits resulted in an increased formation of ethyl esters, acetates, acetoxy esters and alcohols, thus allowing the authentication of sea- and air-freighted pineapples, respectively. Particularly, compounds presumably derived from methyl-branched amino acid catabolism were identified in the fruits at later post-harvest stages. In addition, physicochemical traits were determined to characterise the fruit maturity stages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Headspace Solid Phase Microextraction in Pesticide Residues Analysis:1. Optimisation of Extraction Conditions

    Directory of Open Access Journals (Sweden)

    Rada Đurović

    2007-01-01

    Full Text Available The method of headspace solid phase microextraction (HS/SPME was successfully used in a simultaneous multicomponent analysis of hexachlorobenzene (HCB, tefluthrin, heptachlor, aldrin, chlorpyrifos, fenthion and bifenthrin in aqueous medium. Measurementswere performed using a nonpolar polydimethyl siloxane (PDMS fiber. Detection and quantification were done by gas chromatography/mass spectrometry (GC/MS.Optimal conditions for HS/SPME were determined both by performing extraction at different temperatures and examining extraction time profiles at constant temperature. Optimal extraction temperature for each pesticide studied was determined as follows: 60°C for HCB and for heptachlor, 80°C for aldrin and for chlorpyrifos, fenthion and tefluthrin, and temperature exceeding 80°C for bifenthrin. For the pesticide mixture studied, 60°C was identified as the optimum extraction temperature.Based on the time profiles obtained, it was confirmed that satisfactory extraction sensitivity can be obtained even for extraction times shorter than the time required to reach a sorption equilibrium. This conclusion was confirmed by linear concentration profiles obtained for the following ranges: 0.05-10 ng/ml (HCB, 0.05-25 ng/ml (tefluthrin, 0.05-40 ng/ml (heptachlor, 0.05-40 ng/ml (aldrin, 0.05-25 ng/ml (chlorpyrifos, 0.05-25 ng/ml (fenthionand 0.05-25 ng/ml (bifenthrin.Relative standard deviation (RSD values for triplicate measurements did not exceed 15%.

  20. Analysis of Five Earthy-Musty Odorants in Environmental Water by HS-SPME/GC-MS

    Directory of Open Access Journals (Sweden)

    Zhen Ding

    2014-01-01

    Full Text Available The pressing issue of earthy and musty odor compounds in natural waters, which can affect the organoleptic properties of drinking water, makes it a public health concern. A simple and sensitive method for simultaneous analysis of five odorants in environmental water was developed by headspace solid-phase microextraction (HS-SPME coupled to chromatography-mass spectrometry (GC-MS, including geosmin (GSM and 2-methylisoborneol (2-MIB, as well as dimethyl trisulfide (DMTS, β-cyclocitral, and β-ionone. Based on the simple modification of original magnetic stirrer purchased from CORNING (USA, the five target compounds can be separated within 23 min, and the calibration curves show good linearity with a correlation coefficient above 0.999 (levels = 5. The limits of detection (LOD are all below 1.3 ng L−1, and the relative standard deviation (%RSD is between 4.4% and 9.9% (n = 7 and recoveries of the analytes from water samples are between 86.2% and 112.3%. In addition, the storage time experiment indicated that the concentrations did not change significantly for GSM and 2-MIB if they were stored in canonical environment. In conclusion, the method in this study could be applied for monitoring these five odorants in natural waters.

  1. Characterization of the volatile components in green tea by IRAE-HS-SPME/GC-MS combined with multivariate analysis.

    Science.gov (United States)

    Yang, Yan-Qin; Yin, Hong-Xu; Yuan, Hai-Bo; Jiang, Yong-Wen; Dong, Chun-Wang; Deng, Yu-Liang

    2018-01-01

    In the present work, a novel infrared-assisted extraction coupled to headspace solid-phase microextraction (IRAE-HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) was developed for rapid determination of the volatile components in green tea. The extraction parameters such as fiber type, sample amount, infrared power, extraction time, and infrared lamp distance were optimized by orthogonal experimental design. Under optimum conditions, a total of 82 volatile compounds in 21 green tea samples from different geographical origins were identified. Compared with classical water-bath heating, the proposed technique has remarkable advantages of considerably reducing the analytical time and high efficiency. In addition, an effective classification of green teas based on their volatile profiles was achieved by partial least square-discriminant analysis (PLS-DA) and hierarchical clustering analysis (HCA). Furthermore, the application of a dual criterion based on the variable importance in the projection (VIP) values of the PLS-DA models and on the category from one-way univariate analysis (ANOVA) allowed the identification of 12 potential volatile markers, which were considered to make the most important contribution to the discrimination of the samples. The results suggest that IRAE-HS-SPME/GC-MS technique combined with multivariate analysis offers a valuable tool to assess geographical traceability of different tea varieties.

  2. Characterization of the volatile components in green tea by IRAE-HS-SPME/GC-MS combined with multivariate analysis.

    Directory of Open Access Journals (Sweden)

    Yan-Qin Yang

    Full Text Available In the present work, a novel infrared-assisted extraction coupled to headspace solid-phase microextraction (IRAE-HS-SPME followed by gas chromatography-mass spectrometry (GC-MS was developed for rapid determination of the volatile components in green tea. The extraction parameters such as fiber type, sample amount, infrared power, extraction time, and infrared lamp distance were optimized by orthogonal experimental design. Under optimum conditions, a total of 82 volatile compounds in 21 green tea samples from different geographical origins were identified. Compared with classical water-bath heating, the proposed technique has remarkable advantages of considerably reducing the analytical time and high efficiency. In addition, an effective classification of green teas based on their volatile profiles was achieved by partial least square-discriminant analysis (PLS-DA and hierarchical clustering analysis (HCA. Furthermore, the application of a dual criterion based on the variable importance in the projection (VIP values of the PLS-DA models and on the category from one-way univariate analysis (ANOVA allowed the identification of 12 potential volatile markers, which were considered to make the most important contribution to the discrimination of the samples. The results suggest that IRAE-HS-SPME/GC-MS technique combined with multivariate analysis offers a valuable tool to assess geographical traceability of different tea varieties.

  3. Performance Demonstration Program Plan for Analysis of Simulated Headspace Gases

    International Nuclear Information System (INIS)

    2006-01-01

    The Performance Demonstration Program (PDP) for headspace gases distributes sample gases of volatile organic compounds (VOCs) for analysis. Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility's compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document. Participating measurement

  4. Performance Demonstration Program Plan for Analysis of Simulated Headspace Gases

    International Nuclear Information System (INIS)

    2007-01-01

    The Performance Demonstration Program (PDP) for headspace gases distributes blind audit samples in a gas matrix for analysis of volatile organic compounds (VOCs). Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility's compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document

  5. Characterisation of the volatile profile of coconut water from five varieties using an optimised HS-SPME-GC analysis.

    Science.gov (United States)

    Prades, Alexia; Assa, Rebecca Rachel Ablan; Dornier, Manuel; Pain, Jean-Pierre; Boulanger, Renaud

    2012-09-01

    Coconut (Cocos nucifera L.) water is a refreshing tropical drink whose international market has recently been growing. However, little is yet known about its physicochemical composition, particularly its aroma. This study set out to characterise the volatile profile of water from five coconut varieties. Aroma compounds were characterised by headspace solid phase microextraction gas chromatography (HS-SPME-GC) analysis. An experimental design was established to optimise SPME conditions, leading to an equilibration time of 10 min followed by an extraction time of 60 min at 50 °C. Accordingly, immature coconut water from WAT (West African Tall), PB121 (MYD × WAT Hybrid), MYD (Malayan Yellow Dwarf), EGD (Equatorial Guinea Green Dwarf) and THD (Thailand Aromatic Green Dwarf) palms was analysed and described. Ketones were mainly present in the Tall and Hybrid varieties, whereas aldehydes were most abundant in the Dwarf palms. Tall coconut water was characterised by a high lactone content. THD exhibited a high ethyl octanoate level. The cluster analysis of the volatile fraction from the five coconut cultivars was found to be related to their genetic classification. The volatile compounds of immature coconut water from five varieties were characterised for the first time. Volatile profile analysis could be a useful tool for the selection of Dwarf coconut varieties, which are mainly consumed as a beverage. Copyright © 2012 Society of Chemical Industry.

  6. Quantitative and enantioselective analysis of monoterpenes from plant chambers and in ambient air using SPME

    Science.gov (United States)

    Yassaa, N.; Custer, T.; Song, W.; Pech, F.; Kesselmeier, J.; Williams, J.

    2010-11-01

    A headspace solid-phase microextraction (HS-SPME) and gas chromatography/mass spectrometry (GC/MS) system has been developed for quantifying enantiomeric and nonenantiomeric monoterpenes in plant chamber studies and ambient air. Performance of this system was checked using a capillary diffusion system to produce monoterpene standards. The adsorption efficiency, competitive adsorption and chromatographic peak resolution of monoterpene enantiomer pairs were compared for three SPME fibre coatings: 75 μm Carboxen-PDMS (CAR-PDMS), 50/30 μm divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS) and 65 μm divinylbenzene-polydimethylsiloxane (DVB-PDMS). Key parameters such as the linearity and reproducibility of the SPME system have been investigated in this work. The best compromise between the enantiomeric separation of monoterpenes and competitive adsorption of the isoprenoids on the solid SPME fibre coating was found for DVB-PDMS fibres. The optimum conditions using DVB-PDMS fibres were applied to measure the exchange rates of monoterpenes in the emission of Quercus ilex using a laboratory whole plant enclosure under light and dark conditions, as well as in ambient air. With 592 and 223 ng m-2 s-1 respectively, β-myrcene and limonene were the predominant monoterpenes in the emission of Q. ilex. These values were closely comparable to those obtained using a zNose and cartridge GC-FID systems.

  7. Quantitative and enantioselective analysis of monoterpenes from plant chambers and in ambient air using SPME

    Directory of Open Access Journals (Sweden)

    N. Yassaa

    2010-11-01

    Full Text Available A headspace solid-phase microextraction (HS-SPME and gas chromatography/mass spectrometry (GC/MS system has been developed for quantifying enantiomeric and nonenantiomeric monoterpenes in plant chamber studies and ambient air. Performance of this system was checked using a capillary diffusion system to produce monoterpene standards. The adsorption efficiency, competitive adsorption and chromatographic peak resolution of monoterpene enantiomer pairs were compared for three SPME fibre coatings: 75 μm Carboxen-PDMS (CAR-PDMS, 50/30 μm divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS and 65 μm divinylbenzene-polydimethylsiloxane (DVB-PDMS. Key parameters such as the linearity and reproducibility of the SPME system have been investigated in this work. The best compromise between the enantiomeric separation of monoterpenes and competitive adsorption of the isoprenoids on the solid SPME fibre coating was found for DVB-PDMS fibres. The optimum conditions using DVB-PDMS fibres were applied to measure the exchange rates of monoterpenes in the emission of Quercus ilex using a laboratory whole plant enclosure under light and dark conditions, as well as in ambient air. With 592 and 223 ng m−2 s−1 respectively, β-myrcene and limonene were the predominant monoterpenes in the emission of Q. ilex. These values were closely comparable to those obtained using a zNose and cartridge GC-FID systems.

  8. Quality control of raw cows' milk by headspace analysis

    NARCIS (Netherlands)

    Hettinga, K.A.; Valenberg, van H.J.F.; Hooijdonk, van A.C.M.

    2008-01-01

    This study investigated whether headspace analysis of volatile components can be used for monitoring the quality of raw cows¿ milk. The detection of different quality defects caused by cows¿ feed, microbiological and chemical contamination, as well as enzymatic deterioration was studied. Fresh raw

  9. Analysis of Volatile Components of Adenosma indianum (Lour. Merr. by Steam Distillation and Headspace Solid-Phase Microextraction

    Directory of Open Access Journals (Sweden)

    Zhi Zeng

    2013-01-01

    Full Text Available The essential oil of Adenosma indianum (Lour. Merr. plays an important role in its antibacterial and antiphlogistic activities. In this work, the volatile components were extracted by steam distillation (SD and headspace solid-phase microextraction (HS-SPME and analysed by gas chromatography-mass spectrometry (GC-MS. A total of 49 volatile components were identified by GC-MS, and the major volatile components were α-limonene (20.59–35.07%, fenchone (15.79–31.81%, α-caryophyllene (6.98–10.32%, β-caryophyllene (6.98–10.19%, and piperitenone oxide (1.96–11.63%. The comparison of the volatile components from A. indianum (Lour. Merr. grown in two regions of China was reported. Also, the comparison of the volatile components by SD and HS-SPME was discussed. The results showed that the major volatile components of A. indianum (Lour. Merr. from two regions of China were similar but varied with different extraction methods. These results were indicative of the suitability of HS-SPME method for simple, rapid, and solvent-free analysis of the volatile components of the medicinal plants.

  10. Analysis of flavor-related compounds from tabacco using SPME-GC-MS

    Energy Technology Data Exchange (ETDEWEB)

    Park, G.B.; Lee, S.G. [Korea Research Institute of Chemical Technology, Taejeon (Korea)

    2001-04-01

    The flavor-related compounds contained in tobacco were analyzed by selected ion monitoring (SIM) method using headspace SPME gas chromatography-mass spectrometry (GC-MS). Flavor-related compounds were estragole, pulegone, trans-anethole, safrole, piperonal, eugenol, methyleugenol, coumarin, trans-isoeugenol, trans-methyleugenol and myristicin More than one of the flavor-related compounds were detected in the range of 0.001-1.3 {mu}g/g from all brands of tobacco studied. The recovery was ranged from 89.1 to 102.9% and relative standard deviation was ranged from 2.6 to 25.2%. (author). 19 refs., 4 tabs., 2 figs.

  11. Comparison of Spot and Time Weighted Averaging (TWA Sampling with SPME-GC/MS Methods for Trihalomethane (THM Analysis

    Directory of Open Access Journals (Sweden)

    Don-Roger Parkinson

    2016-02-01

    Full Text Available Water samples were collected and analyzed for conductivity, pH, temperature and trihalomethanes (THMs during the fall of 2014 at two monitored municipal drinking water source ponds. Both spot (or grab and time weighted average (TWA sampling methods were assessed over the same two day sampling time period. For spot sampling, replicate samples were taken at each site and analyzed within 12 h of sampling by both Headspace (HS- and direct (DI- solid phase microextraction (SPME sampling/extraction methods followed by Gas Chromatography/Mass Spectrometry (GC/MS. For TWA, a two day passive on-site TWA sampling was carried out at the same sampling points in the ponds. All SPME sampling methods undertaken used a 65-µm PDMS/DVB SPME fiber, which was found optimal for THM sampling. Sampling conditions were optimized in the laboratory using calibration standards of chloroform, bromoform, bromodichloromethane, dibromochloromethane, 1,2-dibromoethane and 1,2-dichloroethane, prepared in aqueous solutions from analytical grade samples. Calibration curves for all methods with R2 values ranging from 0.985–0.998 (N = 5 over the quantitation linear range of 3–800 ppb were achieved. The different sampling methods were compared for quantification of the water samples, and results showed that DI- and TWA- sampling methods gave better data and analytical metrics. Addition of 10% wt./vol. of (NH42SO4 salt to the sampling vial was found to aid extraction of THMs by increasing GC peaks areas by about 10%, which resulted in lower detection limits for all techniques studied. However, for on-site TWA analysis of THMs in natural waters, the calibration standard(s ionic strength conditions, must be carefully matched to natural water conditions to properly quantitate THM concentrations. The data obtained from the TWA method may better reflect actual natural water conditions.

  12. Development of headspace solid-phase microextraction method for ...

    African Journals Online (AJOL)

    A headspace solid-phase microextraction (HS-SPME) method was developed as a preliminary investigation using univariate approach for the analysis of 14 multiclass pesticide residues in fruits and vegetable samples. The gas chromatography mass spectrometry parameters (desorption temperature and time, column flow ...

  13. HS-SPME-GC-MS Analysis of onion (Allium cepa L. and shallot (Allium ascalonicum L.

    Directory of Open Access Journals (Sweden)

    D’Auria, M.

    2017-06-01

    Full Text Available The volatile organic compounds of onion and shallot were determined via HS-SPME-GC-MS. The main components were dipropyldisulphide and allylpropyldisulphide. Thiopropanal S-oxide were detected only in onion volatiles. In shallot is interesting the presence of 2-methyl-2-pentenal, a compound with an intense fruity aroma, that can characterize the different aroma between onion and shallot. The SPME-GC-MS analysis of shallot after absorption on the SPME fiber at 50°C showed the presence of new compounds, whose structures have been discussed.

  14. Organic analysis of the headspace in Hanford waste tanks

    International Nuclear Information System (INIS)

    Lucke, R.B.; McVeety, B.D.; Clauss, T.W.; Fruchter, J.S.; Goheen, S.C.

    1994-01-01

    Before radioactive mixed waste in Hanford waste tanks can be isolated and permanently stored, several safety issues need to be addressed. The headspace vapors in Hanford Tank 103-C raise two issues: (1) the potential flammability of the vapor and aerosol, and (2) the potential worker health and safety hazards associated with the toxicity of the constituents. As a result, the authors have implemented organic analysis methods to characterize the headspace vapors in Hanford waste tanks. To address the flammability issue, they have used OSHA versatile sampling (OVS) tubes as the sampling method followed by solvent extraction and GC/MS analysis. For analyzing volatile organics and organic air toxins, they have implemented SUMMA trademark canisters as the collection device followed by cryogenic trapping and GC/MS analysis. Strategies for modifying existing NIOSH and EPA methods to make them applicable to vapors in Hanford waste tanks are discussed. Identification and quantification results of volatile and semivolatile organics are presented

  15. Headspace techniques in foods, fragrances and flavors: an overview.

    Science.gov (United States)

    Rouseff, R; Cadwallader, K

    2001-01-01

    Headspace techniques have traditionally involved the collection of volatiles in the vapor state under either dynamic or static conditions as a means of determining concentrations in the product of interest. A brief overview of contemporary headspace applications and recent innovations are presented from the literature and Chapters in this book. New approaches used to concentrate volatiles under static conditions such as solid phase micro extraction, SPME, are examined. Advances in purge and trap applications and automation are also presented. Innovative methods of evaluating headspace volatiles using solid state sensor arrays (electronic noses) or mass spectrometers without prior separation are referenced. Numerous food and beverage headspace techniques are also reviewed. Advantages, limitations and alternatives to headspace analysis are presented.

  16. Performance demonstration program plan for analysis of simulated headspace gases

    International Nuclear Information System (INIS)

    1995-06-01

    The Performance Demonstration Program (PDP) for analysis of headspace gases will consist of regular distribution and analyses of test standards to evaluate the capability for analyzing VOCs, hydrogen, and methane in the headspace of transuranic (TRU) waste throughout the Department of Energy (DOE) complex. Each distribution is termed a PDP cycle. These evaluation cycles will provide an objective measure of the reliability of measurements performed for TRU waste characterization. Laboratory performance will be demonstrated by the successful analysis of blind audit samples of simulated TRU waste drum headspace gases according to the criteria set within the text of this Program Plan. Blind audit samples (hereinafter referred to as PDP samples) will be used as an independent means to assess laboratory performance regarding compliance with the QAPP QAOs. The concentration of analytes in the PDP samples will encompass the range of concentrations anticipated in actual waste characterization gas samples. Analyses which are required by the WIPP to demonstrate compliance with various regulatory requirements and which are included in the PDP must be performed by laboratories which have demonstrated acceptable performance in the PDP

  17. Application of headspace and direct immersion solid-phase microextraction in the analysis of organothiophosphates related to the Chemical Weapons Convention from water and complex matrices.

    Science.gov (United States)

    Althoff, Marc André; Bertsch, Andreas; Metzulat, Manfred; Klapötke, Thomas M; Karaghiosoff, Konstantin L

    2017-11-01

    The successful application of headspace (HS) and direct immersion (DI) solid phase microextraction (SPME) for the unambiguous identification and characterization of a series of toxic thiophosphate esters, such as Amiton (I), from aqueous phases and complex matrices (e.g. grass and foliage) has been demonstrated. A Thermo Scientific gas chromatograph (GC) - tandem mass spectrometer (MS/MS) system with a TriPlus RSH® autosampler and a SPME tool was used to investigate the effect of different parameters that influence the extraction efficiency: e.g. pH of the sample matrix and extraction temperature. The developed methods were employed for the detection of several Amiton derivatives (Schedule II of the CWC) that are structurally closely related to each other; some of which are new and have not been reported in literature previously. In addition, a novel DI SPME method from complex matrices for the analysis of organophosphates related to the CWC was developed. The studies clearly show that DI SPME for complex matrices is superior to HS extraction and can potentially be applied to other related compounds controlled under the CWC. Copyright © 2017. Published by Elsevier B.V.

  18. Headspace Solid Phase Microextraction in Pesticide Residues Analysis: 2. Apple Samples

    Directory of Open Access Journals (Sweden)

    Jelena Milinović

    2007-01-01

    Full Text Available Headspace solid phase microextraction method (HS/SPME, optimised previously for pesticide water solutions, was applied to trace residues of the pesticides chlorpyrifos, fenthion and bifenthrin in apple samples. One-hour extraction procedure was performed at 60oC extraction temperature. Nonpolar polydimethyl siloxane (PDMS fiber was used. Detection and quantification were carried out by gas chromatography/mass spectrometry (GC/MS. A non-pesticide treated apple sample was fortified with the pesticides over a 0.025-1.25 mg/kg concentration range in order to determine analytical parameters of the method applied. Linearity with regression coefficient (R values higher than 0.99 were obtained over the whole concentration range investigated for chlorpyrifos and fenthion, while linear dependence was observed in the 0.1-1.25 mg/kg range for bifenthrin. Relative recovery values for samples fortified at different levels were in the 56.68-82.91% range. Limit of detection (LOD values were determined as follows: 0.014 mg/kg for chlorpyrifos, 0.021 mg/kg for fenthion and 0.053 mg/kg for bifenthrin. Relative standard deviation (RSD values obtained for multiple analysis of the sample fortified at 0.6 mg/kg level were not higher than 20%.

  19. Solid phase microextraction headspace sampling of chemical warfare agent contaminated samples : method development for GC-MS analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jackson Lepage, C.R.; Hancock, J.R. [Defence Research and Development Canada, Medicine Hat, AB (Canada); Wyatt, H.D.M. [Regina Univ., SK (Canada)

    2004-07-01

    Defence R and D Canada-Suffield (DRDC-Suffield) is responsible for analyzing samples that are suspected to contain chemical warfare agents, either collected by the Canadian Forces or by first-responders in the event of a terrorist attack in Canada. The analytical techniques used to identify the composition of the samples include gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy. GC-MS and LC-MS generally require solvent extraction and reconcentration, thereby increasing sample handling. The authors examined analytical techniques which reduce or eliminate sample manipulation. In particular, this paper presented a screening method based on solid phase microextraction (SPME) headspace sampling and GC-MS analysis for chemical warfare agents such as mustard, sarin, soman, and cyclohexyl methylphosphonofluoridate in contaminated soil samples. SPME is a method which uses small adsorbent polymer coated silica fibers that trap vaporous or liquid analytes for GC or LC analysis. Collection efficiency can be increased by adjusting sampling time and temperature. This method was tested on two real-world samples, one from excavated chemical munitions and the second from a caustic decontamination mixture. 7 refs., 2 tabs., 3 figs.

  20. SPME GC/MS Analysis of Three Ornithogalum L. species from Turkey

    Directory of Open Access Journals (Sweden)

    Gülin Renda

    2016-01-01

    Full Text Available In this study, a solid phase micro extraction (SPME method with gas chromatography-mass spectrometry (GC-MS was used for analysis of volatile compounds in flowers and bulbs of three Ornithogalum species. The samples of flowers and bulbs of Ornithogalum sigmoideum, Ornithogalum orthophyllum, Ornithogalum oligophyllum was separately analyzed by SPME-GC-MS. A comparison of volatile compounds was made between species and the parts studied. A total of 70 compounds were identified and different volatile compounds were determined in distinct parts of the species. The major volatile organic compound of the flowers of O. sigmoideum and O. ornithogalum was furan (54.5% and 57.0% respectively. For O. oligophyllum the major volatile organic compound was nonanal (19.2%. Analyses revealed that SPME-GC-MS method is appropriate for the analysis of volatile compounds of Ornithogalum species.

  1. Simple and sensitive analysis of nereistoxin and its metabolites in human serum using headspace solid-phase microextraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Namera, A; Watanabe, T; Yashiki, M; Kojima, T; Urabe, T

    1999-03-01

    A simple method for the analysis of nereistoxin and its metabolites in human serum using headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) is developed. A vial containing a serum sample, 5M sodium hydroxide, and benzylacetone (internal standard) is heated to 70 degrees C, and an SPME fiber is exposed for 30 min in the headspace of the vial. The compounds extracted by the fiber are desorbed by exposing the fiber in the injection port of the GC-MS. The calibration curves show linearity in the range of 0.05-5.0 micrograms/mL for nereistoxin and N-methyl-N-(2-methylthio-1-methylthiomethyl)ethylamine, 0.01-5.0 micrograms/mL for S,S'-dimethyl dihydronereistoxin, and 0.5-10 micrograms/mL for 2-methylthio-1-methylthiomethylethylamine in serum. No interferences are found, and the analysis time is 50 min for one sample. In addition, this proposed method is applied to a patient who attempted suicide by ingesting Padan 4R, a herbicide. Padan 4R contains 4% cartap hydrochloride, which is an analogue of nereistoxin. Nereistoxin and its metabolites are detected in the serum samples collected from the patient during hospitalization. The concentration ranges of nereistoxin in the serum are 0.09-2.69 micrograms/mL.

  2. SPME-GC-MS analysis of commercial henna samples (Lawsonia inermis L.).

    Science.gov (United States)

    Mengoni, Tamara; Peregrina, Dolores Vargas; Censi, Roberta; Cortese, Manuela; Ricciutelli, Massimo; Maggi, Filippo; Di Martino, Piera

    2016-01-01

    The aim of this work was to provide a characterisation of volatile constituents from different commercial batches of henna (Lawsonia inermis) leaves of different geographic origin. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used for the purpose. A total of 72 components were identified by GC-MS in the headspace of different henna samples which proved to differ considerably from each other, because they were characterised by different classes of components, mainly aliphatic compounds (9.0-64.7%), terpenoids (5.8-45.5%) and aromatics (7.9-45.2%), with alkanes (0.9-18.5%), aldehydes (2.1-18.8%) and carboxylic acids (3.1-29.3%), monoterpenes (3.4-30.0%) and sesquiterpenes (0.8-23.7%) and phenyl propanoids (0.6-43.1%), being the most abundant, respectively. Major representatives of these groups were n-hexadecane (0.5-4.7%), (2E)-hexenal (0.5-11.7%) and acetic acid (2.8-24.5%), limonene (0.8-14.7%), carvol (3.8-7.1%), geranyl acetone (1.4-7.9%) and (E)-caryophyllene (3.3-8.4%), and (E)-anethole (0.6-35.0%), respectively. We assume that factors such as the manufacturing process, the storage conditions and the different geographic origin of the samples may contribute to such variability.

  3. Analysis of Volatile Markers for Virgin Olive Oil Aroma Defects by SPME-GC/FID: Possible Sources of Incorrect Data.

    Science.gov (United States)

    Oliver-Pozo, Celia; Aparicio-Ruiz, Ramón; Romero, Inmaculada; García-González, Diego L

    2015-12-09

    The need to explain virgin olive oil (VOO) aroma descriptors by means of volatiles has raised interest in applying analytical techniques for trapping and quantitating volatiles. Static headspace sampling with solid phase microextraction (SPME) as trapping material is one of the most applied solutions for analyzing volatiles. The use of an internal standard and the determination of the response factors of the main volatiles seem to guarantee the correct determination of volatile concentrations in VOOs by SPME-GC/FID. This paper, however, shows that the competition phenomena between volatiles in their adsorption to the SPME fiber, inherent in static headspace sampling, may affect the quantitation. These phenomena are more noticeable in the particular case of highly odorant matrices, such as rancid and vinegary VOOs with high intensity of defect. The competition phenomena can modify the measurement sensitivity, which can be observed in volatile quantitation as well as in the recording of internal standard areas in different matrices. This paper analyzes the bias of the peak areas and concentrations of those volatiles that are markers for each sensory defect of VOOs (rancid, vinegary, musty, and fusty) when the intensity and complexity of aroma are increased. Of the 17 volatile markers studied in this work, 10 presented some anomalies in the quantitation in highly odorant matrices due the competition phenomena. However, quantitation was not affected in the concentration ranges at which each volatile marker is typically found in the defective oils they were characteristic of, validating their use as markers.

  4. Dynamic speciation analysis of atrazine in aqueous latex nanoparticle dispersions using solid phase microextraction (SPME)

    NARCIS (Netherlands)

    Benhabib, K.; Town, R.M.; Leeuwen, van H.P.

    2009-01-01

    Solid phase microextraction (SPME) is applied in the dynamic speciation analysis of the pesticide atrazine in an aqueous medium containing sorbing latex nanoparticles. It is found that the overall rate of extraction of the analyte is faster than in the absence of nanoparticles and governed by the

  5. Comparison of the atmospheric- and reduced-pressure HS-SPME strategies for analysis of residual solvents in commercial antibiotics using a steel fiber coated with a multiwalled carbon nanotube/polyaniline nanocomposite.

    Science.gov (United States)

    Ghiasvand, Ali Reza; Nouriasl, Kolsoum; Yazdankhah, Fatemeh

    2018-01-01

    A low-cost, sensitive and reliable reduced-pressure headspace solid-phase microextraction (HS-SPME) setup was developed and evaluated for direct extraction of residual solvents in commercial antibiotics, followed by determination by gas chromatography with flame ionization detection (GC-FID). A stainless steel narrow wire was made porous and adhesive by platinization by a modified electrophoretic deposition method and coated with a polyaniline/multiwalled carbon nanotube nanocomposite. All experimental variables affecting the extraction efficiency were investigated for both atmospheric-pressure and reduced-pressure conditions. Comparison of the optimal experimental conditions and the results demonstrated that the reduced-pressure strategy leads to a remarkable increase in the extraction efficiency and reduction of the extraction time and temperature (10 min, 25 °Ϲ vs 20 min, 40 °Ϲ). Additionally, the reduced-pressure strategy showed better analytical performances compared with those obtained by the conventional HS-SPME-GC-FID method. Limit of detections, linear dynamic ranges, and relative standard deviations of the reduced-pressure HS-SPME procedure for benzene, toluene, ethylbenzene, and xylene (BTEX) in injectable solid drugs were obtained over the ranges of 20-100 pg g -1 , 0.02-40 μg g -1 , and 2.8-10.2%, respectively. The procedure developed was successful for the analysis of BTEX in commercial containers of penicillin, ampicillin, ceftriaxone, and cefazolin. Graphical abstract Schematic representation of the developed RP-HS-SPME setup.

  6. Gas chromatographic-mass spectrometric analysis of urinary volatile organic metabolites: Optimization of the HS-SPME procedure and sample storage conditions.

    Science.gov (United States)

    Živković Semren, Tanja; Brčić Karačonji, Irena; Safner, Toni; Brajenović, Nataša; Tariba Lovaković, Blanka; Pizent, Alica

    2018-01-01

    Non-targeted metabolomics research of human volatile urinary metabolome can be used to identify potential biomarkers associated with the changes in metabolism related to various health disorders. To ensure reliable analysis of urinary volatile organic metabolites (VOMs) by gas chromatography-mass spectrometry (GC-MS), parameters affecting the headspace-solid phase microextraction (HS-SPME) procedure have been evaluated and optimized. The influence of incubation and extraction temperatures and times, coating fibre material and salt addition on SPME efficiency was investigated by multivariate optimization methods using reduced factorial and Doehlert matrix designs. The results showed optimum values for temperature to be 60°C, extraction time 50min, and incubation time 35min. The proposed conditions were applied to investigate urine samples' stability regarding different storage conditions and freeze-thaw processes. The sum of peak areas of urine samples stored at 4°C, -20°C, and -80°C up to six months showed a time dependent decrease over time although storage at -80°C resulted in a slight non-significant reduction comparing to the fresh sample. However, due to the volatile nature of the analysed compounds, more than two cycles of freezing/thawing of the sample stored for six months at -80°C should be avoided whenever possible. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. A rapid screening procedure for the analysis of proliferation compounds in complex matrices using solid phase microextraction (SPME) and SPME with in-situ derivatization

    International Nuclear Information System (INIS)

    Alcaraz, A.; Hulsey, S.S.; Andresen, B.D.

    1995-01-01

    A variety of methods have been established using advanced chromatographic techniques and new detection systems for the analysis of chemical signatures associated with nuclear and chemical weapon (CW) proliferation. Most of these analytical methods are used in the laboratory and seldom applied in the field. The Chemical Weapons Convention (an international treaty to ban chemical weapons) may require the rapid on-site analysis of environmental samples which contain CW agents, their precursors, and/or their degradation products. In addition to the fact that certain countries are involved in CW non-compliance, there is a current uncertainty regarding nuclear proliferation. This also creates new demands on sample work-up and analytical instrumentation use in the field. The isolation and identification of unique chemical signatures in complex samples such as soils, waste tanks, and decontamination solutions would determine non-compliance. However, a primary area of detection research continues to be sample preparation. Most of the established sample cleanup technologies involve liquid/liquid, Soxhlet, or most recently, solid phase extraction (SPE). Despite the success of these traditional sample preparation techniques, they are time consuming and require multi-step procedures (especially when preparing samples for gas chromatographic mass-spectrometric analysis). The goal of this work is to demonstrate the advantages of utilizing SPME and SPME in-situ derivatization techniques to eliminate time consuming steps necessary to prepare a sample for on-site GC-MS. The authors' approach was to compare two SPME fibers and to develop methods to facilitate the isolation of polar and moderately polar proliferation compounds from complex environmental samples. This work will help to evaluate current SPME technologies for use during on-site environmental monitoring analysis

  8. A comparison study on a sulfonated graphene-polyaniline nanocomposite coated fiber for analysis of nicotine in solid samples through the traditional and vacuum-assisted HS-SPME.

    Science.gov (United States)

    Ghiasvand, Alireza; Koonani, Samira; Yazdankhah, Fatemeh; Farhadi, Saeid

    2018-02-05

    A simple, rapid, and reliable headspace solid-phase microextraction (HS-SPME) procedure, reinforced by applying vacuum in the extraction vial, was developed. It was applied for the extraction of nicotine in solid samples prior to determination by gas chromatography-flame ionization detection (GC-FID). First, the surface of a narrow stainless steel wire was made porous and adhesive by platinization to obtain a durable, higher surface area, and resistant fiber. Then, a thin film of sulfonated graphene/polyaniline (Sulf-G/PANI) nanocomposite was synthesized and simultaneously coated on the platinized fiber using the electrophoretic deposition (EPD) method. It was demonstrated that the extraction efficiency remarkably increased by applying the reduced-pressure condition in the extraction vial. To evaluate the conventional HS-SPME and vacuum-assisted HS-SPME (VA-HS-SPME) platforms, all experimental parameters affecting the extraction efficiency including desorption time and temperature, extraction time and temperature and moisture content of sample matrix were optimized. The highest extraction efficiency was obtained at 60°C, 10min (extraction temperature and time) and 280°C, 2min (desorption condition), for VA-HS-SPME strategy, while for conventional HS-SPME the extraction and desorption conditions found to be 100°C, 30min and 280°C, 2min, respectively. The Sulf-G/PANI coated fiber showed high thermal stability, good chemical/mechanical resistance, and long lifetime. For analysis of nicotine in solid samples using VA-HS-SPME-GC-FID, linear dynamic range (LDR) was 0.01-30μgg -1 (R 2 =0.996), the relative standard deviation (RSD%, n=6), for analyses of 1μgg -1 nicotine was calculated 3.4% and limit of detection (LOD) found to be 0.002μgg -1 . The VA-HS-SPME-GC-FID strategy was successfully carried out for quantitation of nicotine in hair and tobacco real samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Optimization of HS-SPME/GC-MS analysis and its use in the profiling of illicit ecstasy tablets (Part 1).

    Science.gov (United States)

    Bonadio, Federica; Margot, Pierre; Delémont, Olivier; Esseiva, Pierre

    2009-05-30

    A headspace solid-phase microextraction procedure (HS-SPME) was developed for the profiling of traces present in 3,4-methylenedioxymethylampethamine (MDMA). Traces were first extracted using HS-SPME and then analyzed by gas chromatography-mass spectroscopy (GC-MS). The HS-SPME conditions were optimized using varying conditions. Optimal results were obtained when 40 mg of crushed MDMA sample was heated at 80 degrees C for 15 min, followed by extraction at 80 degrees C for 15 min with a polydimethylsiloxane/divinylbenzene coated fibre. A total of 31 compounds were identified as traces related to MDMA synthesis, namely precursors, intermediates or by-products. In addition some fatty acids used as tabletting materials and caffeine used as adulterant, were also detected. The use of a restricted set of 10 target compounds was also proposed for developing a screening tool for clustering samples having close profile. 114 seizures were analyzed using an SPME auto-sampler (MultiPurpose Samples MPS2), purchased from Gerstel GMBH & Co. (Germany), and coupled to GC-MS. The data was handled using various pre-treatment methods, followed by the study of similarities between sample pairs based on the Pearson correlation. The results show that HS-SPME, coupled with the suitable statistical method is a powerful tool for distinguishing specimens coming from the same seizure and specimens coming from different seizures. This information can be used by law enforcement personnel to visualize the ecstasy distribution network as well as the clandestine tablet manufacturing.

  10. Herbs and spices: characterization and quantitation of biologically-active markers for routine quality control by multiple headspace solid-phase microextraction combined with separative or non-separative analysis.

    Science.gov (United States)

    Sgorbini, Barbara; Bicchi, Carlo; Cagliero, Cecilia; Cordero, Chiara; Liberto, Erica; Rubiolo, Patrizia

    2015-01-09

    Herbs and spices are used worldwide as food flavoring, thus determination of their identity, origin, and quality is mandatory for safe human consumption. An analysis strategy based on separative (HS-SPME-GC-MS) and non-separative (HS-SPME-MS) approaches is proposed for the volatile fraction of herbs and spices, for quality control and to quantify the aromatic markers with a single analysis directly on the plant material as such. Eight-to-ten lots of each of the following herbs/spices were considered: cloves (Syzygium aromaticum (L.) Merr. & Perry), American peppertree (Schinus molle L.), black pepper and white pepper (Piper nigrum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.). Homogeneity, origin, and chemotypes of the investigated lots of each herb/spice were defined by fingerprinting, through statistical elaboration with principal component analysis (PCA). Characterizing aromatic markers were directly quantified on the solid matrix through multiple headspace extraction-HS-SPME (MHS-SPME). Reliable results were obtained with both separative and non-separative methods (where the latter were applicable); the two were in full agreement, RSD% ranging from 1.8 to 7.7% for eugenol in cloves, 2.2-18.4% for carvacrol+thymol in thyme, and 3.1-16.8% for thujones in sage. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Nanoparticle-Incorporated PDMS Film as an Improved Performance SPME Fiber for Analysis of Volatile Components of Eucalyptus Leaf

    Directory of Open Access Journals (Sweden)

    Parviz Aberoomand Azar

    2013-01-01

    Full Text Available A new fabrication strategy was proposed to prepare polydimethylsiloxane (PDMS- coated solid-phase microextraction (SPME on inexpensive and unbreakable Cu fiber. PDMS was covalently bonded to the Cu substrate using self-assembled monolayer (SAM of (3-mercaptopropyltrimethoxysilane (3MPTS as binder. To increase the performance of the fiber, the incorporation effect of some nanomaterials including silica nanoparticles (NPs, carbon nanotubes (CNTs, and carboxylated carbon nanotubes (CNT-COOH to PDMS coating was compared. The surface morphology of the prepared fibers was characterized by scanning electron microscopy (SEM, and their applicability was evaluated through the extraction of some volatile organic compounds (VOCs of Eucalyptus leaf in headspace mode, and parameters affecting the extraction efficiency including extraction temperature and extraction time were optimized. Extracted compounds were analyzed by GC-MS instrument. The results obtained indicated that prepared fibers have some advantages relative to previously prepared SPME fibers, such as higher thermal stability and improved performance of the fiber. Also, results showed that SPME is a fast, simple, quick, and sensitive technique for sampling and sample introduction of Eucalyptus VOCs.

  12. Quantification of selected volatile organic compounds in human urine by gas chromatography selective reagent ionization time of flight mass spectrometry (GC-SRI-TOF-MS) coupled with head-space solid-phase microextraction (HS-SPME).

    Science.gov (United States)

    Mochalski, Paweł; Unterkofler, Karl

    2016-08-07

    Selective reagent ionization time of flight mass spectrometry with NO(+) as the reagent ion (SRI-TOF-MS(NO(+))) in conjunction with gas chromatography (GC) and head-space solid-phase microextraction (HS-SPME) was used to determine selected volatile organic compounds in human urine. A total of 16 volatiles exhibiting high incidence rates were quantified in the urine of 19 healthy volunteers. Amongst them there were ten ketones (acetone, 2-butanone, 3-methyl-2-butanone, 2-pentanone, 3-methyl-2-pentanone, 4-methyl-2-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, and 4-heptanone), three volatile sulphur compounds (dimethyl sulfide, allyl methyl sulfide, and methyl propyl sulfide), and three heterocyclic compounds (furan, 2-methylfuran, 3-methylfuran). The concentrations of the species under study varied between 0.55 nmol L(-1) (0.05 nmol mmol(-1)creatinine) for allyl methyl sulfide and 11.6 μmol L(-1) (1.54 μmol mmol(-1)creatinine) for acetone considering medians. Limits of detection (LODs) ranged from 0.08 nmol L(-1) for allyl methyl sulfide to 1.0 nmol L(-1) for acetone and furan (with RSDs ranging from 5 to 9%). The presented experimental setup assists both real-time and GC analyses of volatile organic compounds, which can be performed consecutively using the same analytical system. Such an approach supports the novel concept of hybrid volatolomics, an approach which combines VOC profiles obtained from two or more body fluids to improve and complement the chemical information on the physiological status of an individual.

  13. Analysis of volatiles in silver carp by headspace solid phase micro-extraction coupled with GC-MS

    International Nuclear Information System (INIS)

    Yang Yuping; Xiong Guangquan; Cheng Wei; Liao Tao; Lin Ruotai; Geng Shengrong; Li Xin; Li Xiaoding; Wu Wenjin

    2010-01-01

    In this paper, a method for the determination of volatiles using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was presented. The extraction conditions were optimized with reference to these volatiles as hexanal, heptanal, benzaldehyde, 1-Octen-3-ol, octanal, nonanal, decenal, 2,4-heptadienal and 2,4-decadienal. The extraction of fish muscle followed by incubation on a StableFlex divinyl benzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber during 50 in at 60 obtained the most effective extraction of the analytes. The methods by HS-SPME and GC-MS were effective in detecting volatiles in the gills, scales, viscera and fish muscles. The types of volatiles in the gill were more than other organs and the number of odors compounds was 63, and the number of volatiles in scales, viscera and fish muscles was 48, 44 and 42 respectively. (authors)

  14. Application of Microextraction Techniques Including SPME and MESI to the Thermal Degradation of Polymers: A Review.

    Science.gov (United States)

    Kaykhaii, Massoud; Linford, Matthew R

    2017-03-04

    Here, we discuss the newly developed micro and solventless sample preparation techniques SPME (Solid Phase Microextraction) and MESI (Membrane Extraction with a Sorbent Interface) as applied to the qualitative and quantitative analysis of thermal oxidative degradation products of polymers and their stabilizers. The coupling of these systems to analytical instruments is also described. Our comprehensive literature search revealed that there is no previously published review article on this topic. It is shown that these extraction techniques are valuable sample preparation tools for identifying complex series of degradation products in polymers. In general, the number of products identified by traditional headspace (HS-GC-MS) is much lower than with SPME-GC-MS. MESI is particularly well suited for the detection of non-polar compounds, therefore number of products identified by this technique is not also to the same degree of SPME. Its main advantage, however, is its ability of (semi-) continuous monitoring, but it is more expensive and not yet commercialized.

  15. (E-2-Nonenal determination in brazilian beers using headspace solid-phase microextraction and gas chromatographic coupled mass spectrometry (HS-SPME-GC-MS Determinação de (E-2-nonenal em cervejas brasileiras utilizando microextração em fase sólida do headspace e cromatografia gasosa acoplada a espectrometria de massas

    Directory of Open Access Journals (Sweden)

    Rodrigo Scherer

    2010-05-01

    Full Text Available (E-2-nonenal is considered an important off-flavor of beer, related to the flavor of beer staling. In this study, a new method for determination of (E-2-nonenal in beer using headspace solid-phase microextraction and gas chromatographic coupled mass spectrometry (HS-SPME-GC-MS was developed and applied in Brazilian beer samples. The extractions were carried out in CAR-PDMS (carboxen-polydimethylsiloxane fiber and the best results were found with 15 minutes of equilibrium and 90 minutes of extraction at 50 °C. The method was linear in the range from 0.02 to 4.0 μg.L-1 with correlation coefficient of 0.9994. The limits of detection and quantification were 0.01 and 0.02 μg.L-1, respectively. 96.5% of recovery and 4% precision (RSD were obtained in the fortification of beer samples with 2.0 μg.L-1 of (E-2-nonenal. The developed method proved to be simple, efficient and highly sensitive to the determination of this analyte being easily applied in the quality control of the brewery. (E-2-nonenal was found in all beer samples analyzed with levels between 0.17 and 0.42 μg.L-1.O (E-2-nonenal é considerado um importante off-flavor da cerveja, sendo relacionado ao sabor de cerveja envelhecida. Neste estudo, um novo método para determinação de (E-2-nonenal em cerveja usando microextração em fase sólida do headspace e cromatografia a gás acoplada à espectrometria de massa (HS-SPME-GC-MS foi desenvolvido e aplicado em amostras de cerveja brasileira. As extrações foram realizadas utilizando a fibra CAR/PDMS (carboxen/polidimetilsiloxano, com 15 minutos de tempo de equilíbrio e 90 minutos de exposição da fibra a 50 °C. O método foi linear na faixa de 0,02 e 4,0 μg.L-1, com coeficiente de correlação de 0,9994. Os limites de detecção e quantificação foram 0,01 e 0,02 μg.L-1, respectivamente. Foram obtidos 96,5% de recuperação e 4% de variação entre replicatas de amostras de cerveja fortificadas com 2,0 μg.L-1 de (E-2-nonenal. O m

  16. An Innovative Rapid Method for Analysis of 10 Organophosphorus Pesticide Residues in Wheat by HS-SPME-GC-FPD/MSD.

    Science.gov (United States)

    Du, Xin; Ren, YongLin; Beckett, Stephen J

    2016-01-01

    The rapid detection of pesticide residues in wheat has become a top food security priority. A solvent-free headspace solid-phase microextraction (HS-SPME) has been evaluated for rapid screening of organophosphorus pesticide (OPP) residues in wheat with high sensitivity. Individual wheat samples (1.7 g), spiked with 10 OPPs, were placed in a 4 mL sealed amber glass vial and heated at 60°C for 45 min. During this time, the OPP residues were extracted with a 50 μm/30 μm divinylbenzene (DVB)/carboxen (CAR)/plasma desorption mass spectroscopy polydimethylsiloxane (PDMS) fiber from the headspace above the sample. The fiber was then removed and injected into the GC injection port at 250°C for desorption of the extracted chemicals. The multiple residues were identified by a GC mass spectrometer detector (GC-MSD) and quantified with a GC flame photometric detector (GC-FPD). Seven spiked levels of 10 OPPs on wheat were analyzed. The GC responses for a 50 μm/30 μm DVB/CAR/PDMS fiber increased with increasing spiking levels, yielding significant (R(2) > 0.98) linear regressions. The lowest LODs of the multiple pesticide standards were evaluated under the conditions of the validation study in a range of levels from 0 (control) to 100 ng of pesticide residue per g of wheat that separated on a low-polar GC capillary column (Agilent DB-35UI). The results of the HS-SPME method were compared with the QuEChERS AOAC 2007.01 method and they showed several advantages over the latter. These included improved sensitivity, selectivity, and simplicity.

  17. Automated headspace solid-phase dynamic extraction to analyse the volatile fraction of food matrices.

    Science.gov (United States)

    Bicchi, Carlo; Cordero, Chiara; Liberto, Erica; Rubiolo, Patrizia; Sgorbini, Barbara

    2004-01-23

    High concentration capacity headspace techniques (headspace solid-phase microextraction (HS-SPME) and headspace sorptive extraction (HSSE)) are a bridge between static and dynamic headspace, since they give high concentration factors as does dynamic headspace (D-HS), and are as easy to apply and as reproducible as static headspace (S-HS). In 2000, Chromtech (Idstein, Germany) introduced an inside-needle technique for vapour and liquid sampling, solid-phase dynamic extraction (SPDE), also known as "the magic needle". In SPDE, analytes are concentrated on a 50 microm film of polydimethylsiloxane (PDMS) and activated carbon (10%) coated onto the inside wall of the stainless steel needle (5 cm) of a 2.5 ml gas tight syringe. When SPDE is used for headspace sampling (HS-SPDE), a fixed volume of the headspace of the sample under investigation is sucked up an appropriate number of times with the gas tight syringe and an analyte amount suitable for a reliable GC or GC-MS analysis accumulates in the polymer coating the needle wall. This article describes the preliminary results of both a study on the optimisation of sampling parameters conditioning HS-SPDE recovery, through the analysis of a standard mixture of highly volatile compounds (beta-pinene, isoamyl acetate and linalool) and of the HS-SPDE-GC-MS analyses of aromatic plants and food matrices. This study shows that HS-SPDE is a successful technique for HS-sampling with high concentration capability, good repeatability and intermediate precision, also when it is compared to HS-SPME.

  18. Experimental design-based isotope-dilution SPME-GC/MS method development for the analysis of smoke flavouring products.

    Science.gov (United States)

    Giri, Anupam; Zelinkova, Zuzana; Wenzl, Thomas

    2017-12-01

    For the implementation of Regulation (EC) No 2065/2003 related to smoke flavourings used or intended for use in or on foods a method based on solid-phase micro extraction (SPME) GC/MS was developed for the characterisation of liquid smoke products. A statistically based experimental design (DoE) was used for method optimisation. The best general conditions to quantitatively analyse the liquid smoke compounds were obtained with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre, 60°C extraction temperature, 30 min extraction time, 250°C desorption temperature, 180 s desorption time, 15 s agitation time, and 250 rpm agitation speed. Under the optimised conditions, 119 wood pyrolysis products including furan/pyran derivatives, phenols, guaiacol, syringol, benzenediol, and their derivatives, cyclic ketones, and several other heterocyclic compounds were identified. The proposed method was repeatable (RSD% <5) and the calibration functions were linear for all compounds under study. Nine isotopically labelled internal standards were used for improving quantification of analytes by compensating matrix effects that might affect headspace equilibrium and extractability of compounds. The optimised isotope dilution SPME-GC/MS based analytical method proved to be fit for purpose, allowing the rapid identification and quantification of volatile compounds in liquid smoke flavourings.

  19. Analysis of Cyanide in Blood by Headspace-Isotope-Dilution-GC-MS

    DEFF Research Database (Denmark)

    Løbger, Lise Lotte; Petersen, Henning Willads; Andersen, Jens Enevold Thaulov

    2008-01-01

    An uncomplicated, rapid, automated procedure for the analysis of low cyanide concentrations in whole blood is reported. The analysis was performed by headspace gas chromatography and mass spectrometry in the (1H12C14N) and m/z 29 (1H13C15N). Carryover from cyanide adsorption onto the surface...

  20. Polyelectrolyte coatings prevent interferences from charged nanoparticles in SPME speciation analysis

    International Nuclear Information System (INIS)

    Zielińska, Katarzyna; Leeuwen, Herman P. van

    2014-01-01

    Highlights: • For the first time SPME fiber is coated with polyelectrolyte layer. • Sorption of nanoparticles on the solid phase surface is prevented. • Polyelectrolyte-modified fiber enables extraction of free analyte in presence of sorbing nanoparticles. - Abstract: In this work we present a new approach for protection of the fiber in solid phase microextraction (SPME) from interfering charged particles present in the sample medium. It involves coating of commercial poly(dimethylsiloxane) extraction phase with polyelectrolyte layer composed of poly(diallyldimethylammonium chloride), and poly(sodium 4-styrenesulfonate). The modified fiber provides reproducible, convenient and fast extraction capabilities toward the model analyte, triclosan (TCS). A negatively charged polyelectrolyte coating prevents sorbing oxidic nanoparticles from both partitioning into the PDMS phase and aggregation at its surface. The results for the TCS/nanoparticle sample show that the polyelectrolyte layer-modified solid phase extracts just the free form of the organic compound and enables dynamic speciation analysis of the nanoparticulate target analyte complex

  1. New insight on biological interaction analysis: new nanocrystalline mixed metal oxide SPME fiber for GC-FID analysis of BTEX and its application in human hemoglobin-benzene interaction studies.

    Directory of Open Access Journals (Sweden)

    Reza Hosseinzadeh

    Full Text Available Nanocrystalline mixed metal oxides (MMO of various metal cations were synthesized and were used for coating a piece of copper wire as a new high sensitive solid phase micro extraction (SPME fiber in extraction and determination of BTEX compounds from the headspace of aqueous samples prior to GC-FID analysis. Under optimum extraction conditions, the proposed fiber exhibited low detection limits, and quantification limits, good reproducibility, simple and fast preparation method, high fiber capacity and high thermal and mechanical durability. These are some of the most important advantages of the new fiber. The proposed fiber was used for human hemoglobin upon interaction with benzene. Binding isotherm, Scatchard and Klotz logarithmic plots were constructed using HS-SPME-GC data, accurately. The obtained binding isotherm analyzed using Hill method. The Hill parameters have been obtained by calculating saturation parameter from the ratio of measured chromatographic peak areas in the presence and absence of hemoglobin. In this interaction, Hill coefficient and Hill constant determined as (nH = 6.14 and log KH = 6.47 respectively. These results reveal the cooperativity of hemoglobin upon interaction with benzene.

  2. Determinação de metil-etil-cetona em amostras de urina com amostragem por micro extração em fase sólida (MEFS em headspace associada à cromatografia gasosa com detector de ionização de chama (CG-DIC Determination of methyl ethyl ketone in urine samples by headspace solid phase micro extraction (SPME sampling associated to gas chromatography with flame-ionization detectoR (GC-FID

    Directory of Open Access Journals (Sweden)

    Marina Venzon Antunes

    2008-01-01

    Full Text Available Methyl ethyl ketone (MEK is a solvent commonly used in chemical, paint and shoe industry. The aim of this study was to develop and validate a method for urinary quantification of MEK, employing headspace solid phase micro extraction sampling (SPME coupled to gas chromatography with flame ionization detection (GC-FID. The calibration curve (y=4.6851x-0.0011 presented good linearity with r²=0.9993. Accuracy (94-109%, intra-assay precision (4.07-5.91% and inter-assay precision (3.03-5.62% were acceptable. The quantification limit was 0.19 mg/L. This low cost method can be used routinely in the biological monitoring of occupational exposure to MEK, according to the requirements of the Brazilian legislation.

  3. Improving Student Understanding of Qualitative and Quantitative Analysis via GC/MS Using a Rapid SPME-Based Method for Determination of Trihalomethanes in Drinking Water

    Science.gov (United States)

    Huang, Shu Rong; Palmer, Peter T.

    2017-01-01

    This paper describes a method for determination of trihalomethanes (THMs) in drinking water via solid-phase microextraction (SPME) GC/MS as a means to develop and improve student understanding of the use of GC/MS for qualitative and quantitative analysis. In the classroom, students are introduced to SPME, GC/MS instrumentation, and the use of MS…

  4. Optimizing headspace sampling temperature and time for analysis of volatile oxidation products in fish oil

    DEFF Research Database (Denmark)

    Rørbæk, Karen; Jensen, Benny

    1997-01-01

    Headspace-gas chromatography (HS-GC), based on adsorption to Tenax GR(R), thermal desorption and GC, has been used for analysis of volatiles in fish oil. To optimize sam sampling conditions, the effect of heating the fish oil at various temperatures and times was evaluated from anisidine values (AV...

  5. Optimization of headspace experimental factors to determine chlorophenols in water by means of headspace solid-phase microextraction and gas chromatography coupled with mass spectrometry and parallel factor analysis.

    Science.gov (United States)

    Morales, Rocío; Cruz Ortiz, M; Sarabia, Luis A

    2012-11-19

    In this work an analytical procedure based on headspace solid-phase microextraction and gas chromatography coupled with mass spectrometry (HS-SPME-GC/MS) is proposed to determine chlorophenols with prior derivatization step to improve analyte volatility and therefore the decision limit (CCα). After optimization, the analytical procedure was applied to analyze river water samples. The following analytes are studied: 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TrCP), 2,3,4,6-tetrachlorophenol (2,4,6-TeCP) and pentachlorophenol (PCP). A D-optimal design is used to study the parameters affecting the HS-SPME process and the derivatization step. Four experimental factors at two levels and one factor at three levels were considered: (i) equilibrium/extraction temperature, (ii) extraction time, (iii) sample volume, (iv) agitation time and (v) equilibrium time. In addition two interactions between four of them were considered. The D-optimal design enables the reduction of the number of experiments from 48 to 18 while maintaining enough precision in the estimation of the effects. As every analysis took 1h, the design is blocked in 2 days. The second-order property of the PARAFAC (parallel factor analysis) decomposition avoids the need of fitting a new calibration model each time that the experimental conditions change. In consequence, the standardized loadings in the sample mode estimated by a PARAFAC decomposition are the response used in the design because they are proportional to the amount of analyte extracted. It has been found that block effect is significant and that 60°C equilibrium temperature together with 25min extraction time are necessary to achieve the best extraction for the chlorophenols analyzed. The other factors and interactions were not significant. After that, a calibration based in a PARAFAC2 decomposition provided the following values of CCα: 120, 208, 86, 39ngL(-1) for 2,4-DCP, 2,4,6-TrCP, 2,3,4,5-TeCP and PCP respectively for a

  6. Discrimination of cherry wines based on their sensory properties and aromatic fingerprinting using HS-SPME-GC-MS and multivariate analysis.

    Science.gov (United States)

    Xiao, Zuobing; Liu, Shengjiang; Gu, Yongbo; Xu, Na; Shang, Yi; Zhu, Jiancai

    2014-03-01

    Volatiles of cherry wines were extracted by headspace solid phase microextraction (HS-SPME) and analyzed by gas chromatography mass spectrometry (GC-MS), multivariate statistical techniques (such as principal component analysis (PCA) and cluster analysis (CA) and correlation analysis) to differentiate sensory attributes of 3 groups of the wines through characterization of volatiles of cherry wine. Seventy-five volatiles were identified in 9 samples, including 29 esters, 22 alcohols, 8 acids, 3 ketones, 5 aldehydes, and 8 miscellaneous compounds. The PCA results showed that the cherry wines were mainly differentiated by 8 sensory attributes. The samples W2, W4, and W7 were grouped around sweet aromatic and the samples W1, W5, and W9 were highly associated with the sweet, esters, green, bitter, and fermented. Nevertheless, the samples W3, W6, and W8 were located close to the sour, alcoholic, and fruity. The final result of correlation analysis was in conformity with the conclusion of PCA. The CA results showed that the group of W2, W4, and W7, and the group of W1, W5, and W9 had less difference than the group of W3, W6, and W8. The reason should be that esterification reactions and fermentation process during the ageing period was more extended. The results of analyzing revealed that HS-SPME-GC-MS coupled with chemometrics could give an appropriate way of characterizing and classifying the cherry wines. Attributes that represent and discriminate among cherry wines might be made use of a better comprehending of the wines and for being utilized in future work. In addition, several chemometrics were used to classify the type of wines and try to install the relationship between volatiles and sensory property. Especially, PCA clearly revealed that the most contributing compounds for sensory attributes of cherry wines, CA was a more applicable way to distinguish types of cherry wines. Therefore, a feasible method that would be helpful to promote the quality of the wines by

  7. GC-MS analysis of headspace and liquid extracts for metabolomic differentiation of citrus Huanglongbing and zinc deficiency in leaves of 'Valencia' sweet orange from commercial groves.

    Science.gov (United States)

    Cevallos-Cevallos, Juan Manuel; García-Torres, Rosalía; Etxeberria, Edgardo; Reyes-De-Corcuera, José Ignacio

    2011-01-01

    Citrus Huanglongbing (HLB) is considered the most destructive citrus disease worldwide. Symptoms-based detection of HLB is difficult due to similarities with zinc deficiency. To find metabolic differences between leaves from HLB-infected, zinc-deficient, and healthy 'Valencia' orange trees by using GC-MS based metabolomics. Analysis based on GC-MS methods for untargeted metabolite analysis of citrus leaves was developed and optimized. Sample extracts from healthy, zinc deficient, or HLB-infected sweet orange leaves were submitted to headspace solid phase micro-extraction (SPME) and derivatization treatments prior to GC-MS analysis. Principal components analysis achieved correct classification of all the derivatized liquid extracts. Analysis of variance revealed 6 possible biomarkers for HLB, of which 5 were identified as proline, β-elemene, (-)trans- caryophyllene, and α-humulene. Significant (P < 0.05) differences in oxo-butanedioic acid, arabitol, and neo-inositol were exclusively detected in samples from plants with zinc deficiency. Levels of isocaryophyllen, α-selinene, β-selinene, and fructose were significantly (P < 0.05) different in healthy leaves only. Results suggest the potential of using identified HLB biomarkers for rapid differentiation of HLB from zinc deficiency. Copyright © 2010 John Wiley & Sons, Ltd.

  8. Gram-negative and -positive bacteria differentiation in blood culture samples by headspace volatile compound analysis.

    Science.gov (United States)

    Dolch, Michael E; Janitza, Silke; Boulesteix, Anne-Laure; Graßmann-Lichtenauer, Carola; Praun, Siegfried; Denzer, Wolfgang; Schelling, Gustav; Schubert, Sören

    2016-12-01

    Identification of microorganisms in positive blood cultures still relies on standard techniques such as Gram staining followed by culturing with definite microorganism identification. Alternatively, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or the analysis of headspace volatile compound (VC) composition produced by cultures can help to differentiate between microorganisms under experimental conditions. This study assessed the efficacy of volatile compound based microorganism differentiation into Gram-negatives and -positives in unselected positive blood culture samples from patients. Headspace gas samples of positive blood culture samples were transferred to sterilized, sealed, and evacuated 20 ml glass vials and stored at -30 °C until batch analysis. Headspace gas VC content analysis was carried out via an auto sampler connected to an ion-molecule reaction mass spectrometer (IMR-MS). Measurements covered a mass range from 16 to 135 u including CO2, H2, N2, and O2. Prediction rules for microorganism identification based on VC composition were derived using a training data set and evaluated using a validation data set within a random split validation procedure. One-hundred-fifty-two aerobic samples growing 27 Gram-negatives, 106 Gram-positives, and 19 fungi and 130 anaerobic samples growing 37 Gram-negatives, 91 Gram-positives, and two fungi were analysed. In anaerobic samples, ten discriminators were identified by the random forest method allowing for bacteria differentiation into Gram-negative and -positive (error rate: 16.7 % in validation data set). For aerobic samples the error rate was not better than random. In anaerobic blood culture samples of patients IMR-MS based headspace VC composition analysis facilitates bacteria differentiation into Gram-negative and -positive.

  9. Dynamic Headspace Sampling as an Initial Step for Sample Preparation in Chromatographic Analysis.

    Science.gov (United States)

    Wojnowski, Wojciech; Majchrzak, Tomasz; Dymerski, Tomasz; Gębicki, Jacek; Namieśnik, Jacek

    2017-11-01

    This work represents a brief summary of the use of dynamic headspace (DHS) as a technique for sample preparation in chromatographic analysis. Despite numerous developments in the area of analyte isolation and enrichment, DHS remains one of the fundamental methods used with GC. In our opinion, interest in this technique will not diminish significantly because it conforms to stipulations of green analytical chemistry. Moreover, DHS fulfills the need for methods that facilitate detection and determination of analytes present at ultratrace levels in complex matrixes. The main focus of this work was placed on the theoretical fundamentals of this method. Also described herein were DHS development, the advantages and disadvantages of this technique compared with other headspace sampling techniques, and selected examples of its applications in food and environmental analyses.

  10. Organic analysis of the headspace of Hanford waste Tank 241-C-103

    International Nuclear Information System (INIS)

    Goheen, S.C.; McVeety, B.D.; Clauss, T.W.; Lucke, R.B.; Ligotke, M.W.; Edwards, J.A.; Fruchter, J.S.

    1996-01-01

    Organic species from the headspace of one Hanford radioactive waste tank are described. Samples were collected either using a sorbent trap or a SUMMA TM canister and were analyzed by gas chromatography and mass spectrometry. The headspace contained several organic components, including alkanes, alkanes, ketones, aldehydes, organic nitriles, and chlorinated hydrocarbons. Sorbent trap samples were designed to collect only normal paraffin hydrocarbons (NPHs). A comparison of NPH data from sorbent traps and SUMMA TM cans revealed results of 693 and 1320 mg/m 3 , NPH respectively. Significant differences were observed in NPH values when samples were collected at different times, or at different locations in the tank. These data suggest either the time of collection, or the position of the sampling device are important variables in the analysis of organic species from Hanford tanks. (author). 16 refs., 3 figs., 2 tabs

  11. Multivariate analysis of volatile compounds detected by headspace solid-phase microextraction/gas chromatography: A tool for sensory classification of cork stoppers.

    Science.gov (United States)

    Prat, Chantal; Besalú, Emili; Bañeras, Lluís; Anticó, Enriqueta

    2011-06-15

    The volatile fraction of aqueous cork macerates of tainted and non-tainted agglomerate cork stoppers was analysed by headspace solid-phase microextraction (HS-SPME)/gas chromatography. Twenty compounds containing terpenoids, aliphatic alcohols, lignin-related compounds and others were selected and analysed in individual corks. Cork stoppers were previously classified in six different classes according to sensory descriptions including, 2,4,6-trichloroanisole taint and other frequent, non-characteristic odours found in cork. A multivariate analysis of the chromatographic data of 20 selected chemical compounds using linear discriminant analysis models helped in the differentiation of the a priori made groups. The discriminant model selected five compounds as the best combination. Selected compounds appear in the model in the following order; 2,4,6 TCA, fenchyl alcohol, 1-octen-3-ol, benzyl alcohol and benzothiazole. Unfortunately, not all six a priori differentiated sensory classes were clearly discriminated in the model, probably indicating that no measurable differences exist in the chromatographic data for some categories. The predictive analyses of a refined model in which two sensory classes were fused together resulted in a good classification. Prediction rates of control (non-tainted), TCA, musty-earthy-vegetative, vegetative and chemical descriptions were 100%, 100%, 85%, 67.3% and 100%, respectively, when the modified model was used. The multivariate analysis of chromatographic data will help in the classification of stoppers and provide a perfect complement to sensory analyses. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Analysis of hydrogen and methane in seawater by "Headspace" method: Determination at trace level with an automatic headspace sampler.

    Science.gov (United States)

    Donval, J P; Guyader, V

    2017-01-01

    "Headspace" technique is one of the methods for the onboard measurement of hydrogen (H 2 ) and methane (CH 4 ) in deep seawater. Based on the principle of an automatic headspace commercial sampler, a specific device has been developed to automatically inject gas samples from 300ml syringes (gas phase in equilibrium with seawater). As valves, micro pump, oven and detector are independent, a gas chromatograph is not necessary allowing a reduction of the weight and dimensions of the analytical system. The different steps from seawater sampling to gas injection are described. Accuracy of the method is checked by a comparison with the "purge and trap" technique. The detection limit is estimated to 0.3nM for hydrogen and 0.1nM for methane which is close to the background value in deep seawater. It is also shown that this system can be used to analyze other gases such as Nitrogen (N 2 ), carbon monoxide (CO), carbon dioxide (CO 2 ) and light hydrocarbons. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Parameters optimization using experimental design for headspace solid phase micro-extraction analysis of short-chain chlorinated paraffins in waters under the European water framework directive.

    Science.gov (United States)

    Gandolfi, F; Malleret, L; Sergent, M; Doumenq, P

    2015-08-07

    The water framework directives (WFD 2000/60/EC and 2013/39/EU) force European countries to monitor the quality of their aquatic environment. Among the priority hazardous substances targeted by the WFD, short chain chlorinated paraffins C10-C13 (SCCPs), still represent an analytical challenge, because few laboratories are nowadays able to analyze them. Moreover, an annual average quality standards as low as 0.4μgL(-1) was set for SCCPs in surface water. Therefore, to test for compliance, the implementation of sensitive and reliable analysis method of SCCPs in water are required. The aim of this work was to address this issue by evaluating automated solid phase micro-extraction (SPME) combined on line with gas chromatography-electron capture negative ionization mass spectrometry (GC/ECNI-MS). Fiber polymer, extraction mode, ionic strength, extraction temperature and time were the most significant thermodynamic and kinetic parameters studied. To determine the suitable factors working ranges, the study of the extraction conditions was first carried out by using a classical one factor-at-a-time approach. Then a mixed level factorial 3×2(3) design was performed, in order to give rise to the most influent parameters and to estimate potential interactions effects between them. The most influent factors, i.e. extraction temperature and duration, were optimized by using a second experimental design, in order to maximize the chromatographic response. At the close of the study, a method involving headspace SPME (HS-SPME) coupled to GC/ECNI-MS is proposed. The optimum extraction conditions were sample temperature 90°C, extraction time 80min, with the PDMS 100μm fiber and desorption at 250°C during 2min. Linear response from 0.2ngmL(-1) to 10ngmL(-1) with r(2)=0.99 and limits of detection and quantification, respectively of 4pgmL(-1) and 120pgmL(-1) in MilliQ water, were achieved. The method proved to be applicable in different types of waters and show key advantages, such

  14. Investigation of a Quantitative Method for the Analysis of Chiral Monoterpenes in White Wine by HS-SPME-MDGC-MS of Different Wine Matrices

    Directory of Open Access Journals (Sweden)

    Mei Song

    2015-04-01

    Full Text Available A valid quantitative method for the analysis of chiral monoterpenes in white wine using head-space solid phase micro-extraction-MDGC-MS (HS-SPME-MDGC-MS with stable isotope dilution analysis was established. Fifteen compounds: (S-(−-limonene, (R-(+-limonene, (+-(2R,4S-cis-rose oxide, (−-(2S,4R-cis-rose oxide, (−-(2R,4R-trans-rose oxide, (+-(2S,4S-cis-rose oxide, furanoid (+-trans-linalool oxide, furanoid (−-cis-linalool oxide, furanoid (−-trans-linalool oxide, furanoid (+-cis-linalool oxide, (−-linalool, (+-linalool, (−-α-terpineol, (+-α-terpineol and (R-(+-β-citronellol were quantified. Two calibration curves were plotted for different wine bases, with varying residual sugar content, and three calibration curves for each wine base were investigated during a single fiber’s lifetime. This was needed as both sugar content and fiber life impacted the quantification of the chiral terpenes. The chiral monoterpene content of six Pinot Gris wines and six Riesling wines was then analyzed using the verified method. ANOVA with Tukey multiple comparisons showed significant differences for each of the detected chiral compounds in all 12 wines. PCA score plots showed a clear separation between the Riesling and Pinot Gris wines. Riesling wines had greater number of chiral terpenes in comparison to Pinot Gris wines. Beyond total terpene content it is possible that the differences in chiral terpene content may be driving the aromatic differences in white wines.

  15. Analysis of the Volatile Profile of Core Chinese Mango Germplasm by Headspace Solid-Phase Microextraction Coupled with Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Xiao-Wei Ma

    2018-06-01

    Full Text Available Despite abundant published research on the volatile characterization of mango germplasm, the aroma differentiation of Chinese cultivars remains unclear. Using headspace solid phase microextraction (HS-SPME coupled with gas chromatography–mass spectrometry (GC-MS, the composition and relative content of volatiles in 37 cultivars representing the diversity of Chinese mango germplasm were investigated. Results indicated that there are distinct differences in the components and content of volatile compounds among and within cultivars. In total, 114 volatile compounds, including 23 monoterpenes, 16 sesquiterpenes, 29 non-terpene hydrocarbons, 25 esters, 11 aldehydes, five alcohols and five ketones, were identified. The total volatile content among cultivars ranged from 211 to 26,022 μg/kg fresh weight (FW, with 123-fold variation. Terpene compounds were the basic background volatiles, and 34 cultivars exhibited abundant monoterpenes. On the basis of hierarchical cluster analysis (HCA and principal component analysis (PCA, terpinolene and α-pinene were important components constituting the aroma of Chinese mango cultivars. Most obviously, a number of mango cultivars with high content of various aroma components were observed, and they can serve as potential germplasms for both breeding and direct use.

  16. Speciation analysis of organotin compounds in human urine by headspace solid-phase micro-extraction and gas chromatography with pulsed flame photometric detection.

    Science.gov (United States)

    Valenzuela, Aníbal; Lespes, Gaëtane; Quiroz, Waldo; Aguilar, Luis F; Bravo, Manuel A

    2014-07-01

    A new headspace solid-phase micro-extraction (HS-SPME) method followed by gas chromatography with pulsed flame photometric detection (GC-PFPD) analysis has been developed for the simultaneous determination of 11 organotin compounds, including methyl-, butyl-, phenyl- and octyltin derivates, in human urine. The methodology has been validated by the analysis of urine samples fortified with all analytes at different concentration levels, and recovery rates above 87% and relative precisions between 2% and 7% were obtained. Additionally, an experimental-design approach has been used to model the storage stability of organotin compounds in human urine, demonstrating that organotins are highly degraded in this medium, although their stability is satisfactory during the first 4 days of storage at 4 °C and pH=4. Finally, this methodology was applied to urine samples collected from harbor workers exposed to antifouling paints; methyl- and butyltins were detected, confirming human exposure in this type of work environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Fabrication of novel nanoporous array anodic alumina solid-phase microextraction fiber coating and its potential application for headspace sampling of biological volatile organic compounds

    International Nuclear Information System (INIS)

    Zhang Zhuomin; Wang Qingtang; Li Gongke

    2012-01-01

    Highlights: ► Nanoporous array anodic alumina (NAAA) SPME coating was originally prepared. ► NAAA SPME coating achieved excellent enrichment capability and selectivity for VOCs. ► NAAA SPME coating can be applied for the headspace sampling of biological VOCs. - Abstract: In the study, nanoporous array anodic alumina (NAAA) prepared by a simple, rapid and stable two-step anodic oxidization method was introduced as a novel solid-phase microextraction (SPME) fiber coating. The regular nanoporous array structure and chemical composition of NAAA SPME fiber coating was characterized and validated by scanning electron microscopy and energy dispersive spectroscopy, respectively. Compared with the commercial polydimethylsiloxane (PDMS) SPME fiber coating, NAAA SPME fiber coating achieved the higher enrichment capability (1.7–4.7 folds) for the mixed standards of volatile organic compounds (VOCs). The selectivity for volatile alcohols by NAAA SPME fiber coating demonstrated an increasing trend with the increasing polarity of alcohols caused by the gradually shortening carbon chains from 1-undecanol to 1-heptanol or the isomerization of carbon chains of some typical volatile alcohols including 2-ethyl hexanol, 1-octanol, 2-phenylethanol, 1-phenylethanol, 5-undecanol, 2-undecanol and 1-undecanol. Finally, NAAA SPME fiber coating was originally applied for the analysis of biological VOCs of Bailan flower, stinkbug and orange peel samples coupled with gas chromatography–mass spectrometry (GC–MS) detection. Thirty, twenty-seven and forty-four VOCs of Bailan flower, stinkbug and orange peel samples were sampled and identified, respectively. Moreover, the contents of trace 1-octanol and nonanal of real orange peel samples were quantified for the further method validation with satisfactory recoveries of 106.5 and 120.5%, respectively. This work proposed a sensitive, rapid, reliable and convenient analytical method for the potential study of trace and small molecular

  18. Fabrication of novel nanoporous array anodic alumina solid-phase microextraction fiber coating and its potential application for headspace sampling of biological volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Zhuomin [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Wang Qingtang [Key Laboratory of Analysis and Detection for Food Safety of Ministry of Education, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou, Fujian 350002 (China); Li Gongke, E-mail: cesgkl@mail.sysu.edu.cn [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China)

    2012-05-21

    Highlights: Black-Right-Pointing-Pointer Nanoporous array anodic alumina (NAAA) SPME coating was originally prepared. Black-Right-Pointing-Pointer NAAA SPME coating achieved excellent enrichment capability and selectivity for VOCs. Black-Right-Pointing-Pointer NAAA SPME coating can be applied for the headspace sampling of biological VOCs. - Abstract: In the study, nanoporous array anodic alumina (NAAA) prepared by a simple, rapid and stable two-step anodic oxidization method was introduced as a novel solid-phase microextraction (SPME) fiber coating. The regular nanoporous array structure and chemical composition of NAAA SPME fiber coating was characterized and validated by scanning electron microscopy and energy dispersive spectroscopy, respectively. Compared with the commercial polydimethylsiloxane (PDMS) SPME fiber coating, NAAA SPME fiber coating achieved the higher enrichment capability (1.7-4.7 folds) for the mixed standards of volatile organic compounds (VOCs). The selectivity for volatile alcohols by NAAA SPME fiber coating demonstrated an increasing trend with the increasing polarity of alcohols caused by the gradually shortening carbon chains from 1-undecanol to 1-heptanol or the isomerization of carbon chains of some typical volatile alcohols including 2-ethyl hexanol, 1-octanol, 2-phenylethanol, 1-phenylethanol, 5-undecanol, 2-undecanol and 1-undecanol. Finally, NAAA SPME fiber coating was originally applied for the analysis of biological VOCs of Bailan flower, stinkbug and orange peel samples coupled with gas chromatography-mass spectrometry (GC-MS) detection. Thirty, twenty-seven and forty-four VOCs of Bailan flower, stinkbug and orange peel samples were sampled and identified, respectively. Moreover, the contents of trace 1-octanol and nonanal of real orange peel samples were quantified for the further method validation with satisfactory recoveries of 106.5 and 120.5%, respectively. This work proposed a sensitive, rapid, reliable and convenient

  19. Time since discharge of 9mm cartridges by headspace analysis, part 1: Comprehensive optimisation and validation of a headspace sorptive extraction (HSSE) method.

    Science.gov (United States)

    Gallidabino, M; Romolo, F S; Weyermann, C

    2017-03-01

    Estimating the time since discharge of spent cartridges can be a valuable tool in the forensic investigation of firearm-related crimes. To reach this aim, it was previously proposed that the decrease of volatile organic compounds released during discharge is monitored over time using non-destructive headspace extraction techniques. While promising results were obtained for large-calibre cartridges (e.g., shotgun shells), handgun calibres yielded unsatisfying results. In addition to the natural complexity of the specimen itself, these can also be attributed to some selective choices in the methods development. Thus, the present series of paper aimed to more systematically evaluate the potential of headspace analysis to estimate the time since discharge of cartridges through the use of more comprehensive analytical and interpretative techniques. Specifically, in this first part, a method based on headspace sorptive extraction (HSSE) was comprehensively optimised and validated, as the latter recently proved to be a more efficient alternative than previous approaches. For this purpose, 29 volatile organic compounds were preliminary selected on the basis of previous works. A multivariate statistical approach based on design of experiments (DOE) was used to optimise variables potentially involved in interaction effects. Introduction of deuterated analogues in sampling vials was also investigated as strategy to account for analytical variations. Analysis was carried out by selected ion mode, gas chromatography coupled to mass spectrometry (GC-MS). Results showed good chromatographic resolution as well as detection limits and peak area repeatability. Application to 9mm spent cartridges confirmed that the use of co-extracted internal standards allowed for improved reproducibility of the measured signals. The validated method will be applied in the second part of this work to estimate the time since discharge of 9mm spent cartridges using multivariate models. Copyright

  20. Analysis of carbonyl compounds via headspace solid-phase microextraction with on-fiber derivatization and gas chromatographic-ion trap tandem mass spectrometric determination of their O-(2,3,4,5,6-pentafluorobenzyl)oxime derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Schmarr, Hans-Georg [Dienstleistungszentrum Laendlicher Raum (DLR) Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse (Germany)], E-mail: hans-georg.schmarr@dlr.rlp.de; Potouridis, Theodoros; Ganss, Sebastian; Sang, Wei; Koepp, Benedikt; Bokuz, Ursula; Fischer, Ulrich [Dienstleistungszentrum Laendlicher Raum (DLR) Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse (Germany)

    2008-06-09

    An improved method for the analysis of carbonyls is described utilizing a headspace solid-phase microextraction (HS-SPME) step and on-fiber derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) hydrochloride. Thermal desorption of the oxime derivatives formed on the fiber is followed by gas chromatographic separation coupled to an ion trap tandem mass spectrometer (GC-ITMS). Selecting specific fragment ions within the electron ionization (EI{sup +}) mass spectra of these oxime derivatives as precursor ions for MS-MS fragmentation provides a suitable method for the target analysis of individual carbonyl classes, such as alkanals, (E)-2-alkenals, (E,E)-2,4-alkadienals, and others. Retention indices on polar as well as on apolar stationary phases along with EI{sup +} mass spectra patterns are presented for a large set of oxime derivatives, giving valuable information needed for unambiguous assignment of substances in complex sample matrices. The fast sample preparation and derivatization step via HS-SPME can be automated and is applicable to a variety of biological samples and foodstuffs, allowing rapid and sensitive screening analyses of important aldehydic biomarkers and aroma active compounds.

  1. Applications of Solid-Phase Microextraction and Gas Chromatography/Mass Spectrometry (SPME-GC/MS in the Study of Grape and Wine Volatile Compounds

    Directory of Open Access Journals (Sweden)

    Annarita Panighel

    2014-12-01

    Full Text Available Volatile compounds are responsible for the wine “bouquet”, which is perceived by sniffing the headspace of a glass, and of the aroma component (palate-aroma of the overall flavor, which is perceived on drinking. Grape aroma compounds are transferred to the wine and undergo minimal alteration during fermentation (e.g., monoterpenes and methoxypyrazines; others are precursors of aroma compounds which form in winemaking and during wine aging (e.g., glycosidically-bound volatile compounds and C13-norisoprenoids. Headspace solid phase microextraction (HS-SPME is a fast and simple technique which was developed for analysis of volatile compounds. This review describes some SPME methods coupled with gas chromatography/mass spectrometry (GC/MS used to study the grape and wine volatiles.

  2. Analysis of pollutants in air and water using gas chromatography and headspace gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Stenner, H.

    1980-01-01

    The combination 'personal sampling' with headspace gas chromatography to determine traces of formaldehyde, phenol and benzene in air is investigated in this work, with the aim of developing maximum workplace concentration values (MWL values). Further possible applications of gas chromatography in trace analysis in the environmentally protected area. The analysis of chromium in waste waters (Cr III as acetyl acetonate complex) is investigated as further possible application, whereby optimum conditions are obtained. A modified flame ionization detector was used to increase the detection sensitivity.

  3. Headspace Analysis of Volatile Compounds Coupled to Chemometrics in Leaves from the Magnoliaceae Family

    Directory of Open Access Journals (Sweden)

    Mohamed A. Farag

    2015-01-01

    Full Text Available Headspace volatile analysis has been used for volatiles profiling in leaves of 4 Magnolia species with a total of 75 compounds were identified. Monterpene hydrocarbons dominated the volatile blend of M. calophylla (86%, M. acuminata (78%, M. virginiana (70% and M. grandiflora (47% with b -pinene and b -ocimene occurring in the largest amounts, whereas sesquiterpenes were the most abundant compounds in M. grandiflora (39%. High levels of oxygenated compounds were only found in M. virginiana volatile blend (11.4% with 2-phenylethyl alcohol as major component. Hierarchical cluster analysis performed on volatiles content revealed the close relationship between M. acuminata and M. calophylla.

  4. SDE and SPME Analysis of Flavor Compounds in Jin Xuan Oolong Tea.

    Science.gov (United States)

    Sheibani, Ershad; Duncan, Susan E; Kuhn, David D; Dietrich, Andrea M; O'Keefe, Sean F

    2016-02-01

    Simultaneous distillation-extraction (SDE) and solid phase micro extraction (SPME) are procedures used for the isolation of flavor compounds in foods. The purpose of this study was to optimize SDE conditions (solvent and time) and to compare SDE with SPME for the isolation of flavor compounds in Jin Xuan oolong tea using GC-MS and GC-O. The concentration of volatile compounds isolated with diethyl ether was higher (P < 0.05) than for dichloromethane and concentration was higher at 40 min (P < 0.05) than 20 or 60 min extractions. For SDE, 128 volatiles were identified using GC-MS and 45 aroma active compounds using GC-O. Trans-nerolidol was the most abundant compound in oolong tea. The number of volatiles identified using GC-MS was lower in SPME than SDE. For SPME, 59 volatiles and 41 aroma active compounds were identified. The composition of the volatiles isolated by the 2 methods differed considerably but provided complementary information. © 2016 Institute of Food Technologists®

  5. Comparison of different types of coatings in headspace solid phase micro extraction for the analysis of pesticide residues in vegetables and fruits

    International Nuclear Information System (INIS)

    Chai, Mee Kin; Tan, Guan Huat

    2008-01-01

    Despite the continuing development of solid-phase micro extraction (SPME) fiber coatings, their selection presents some difficulties for analytes in choosing the appropriate fiber for a particular application. There are many types of SPME coatings available commercially. The most widely used for determination of pesticide residues in vegetable and fruits are polydimethylsiloxane (PDMS) and polyacrylate (PA). A headspace solid phase micro extraction (HS-SPME) procedure using these two commercialized fibers (PDMS and PA) is presented for the determination of selected groups of organo chlorine and organophosphorus pesticides. The extraction performances of these compounds were compared using these two fibers. The optimal experimental procedures for the adsorption and desorption of pesticides were determined. An explanation for the extraction differences is suggested based on the different thickness, polarity of the polymeric film of fibers and the different extracting matrices. In addition, the higher detector response of the pesticides after addition of aliquots of water and an organic solvent to the vegetable and fruit samples are also discussed. The SPME fibers were reusable until a maximum of 120 extractions. Finally, the optimized procedures were applied successfully for the determination of these compounds in vegetable and fruits samples. Mean recoveries for all pesticides were between 75.0-97 % with RSD below 7 %. (author)

  6. Analysis of Furaneol in tomato using dynamic headspace sampling with sodium sulfate.

    Science.gov (United States)

    Buttery, R G; Takeoka, G R; Naim, M; Rabinowitch, H; Nam, Y

    2001-09-01

    High-flow dynamic headspace sampling with excess anhydrous sodium sulfate was found to be an effective method of isolating Furaneol from fresh tomatoes. Quantitative analysis was carried out by gas chromatography using maltol as internal standard. Furaneol was found in the highest concentrations (660-1100 ppb) in the summer crop of home-grown tomatoes and in some of the greenhouse hydroponically grown tomatoes, which are ripened on the plant before being transported to the supermarkets. Furaneol was found in the lowest concentrations (38-180 ppb) in the common ethylene-ripened, field-grown, supermarket tomatoes.

  7. Headspace analysis gas-phase infrared spectroscopy: a study of xanthate decomposition on mineral surfaces

    Science.gov (United States)

    Vreugdenhil, Andrew J.; Brienne, Stephane H. R.; Markwell, Ross D.; Butler, Ian S.; Finch, James A.

    1997-03-01

    The O-ethyldithiocarbonate (ethyl xanthate, CH 3CH 2OCS -2) anion is a widely used reagent in mineral processing for the separation of sulphide minerals by froth flotation. Ethyl xanthate interacts with mineral powders to produce a hydrophobic layer on the mineral surface. A novel infrared technique, headspace analysis gas-phase infrared spectroscopy (HAGIS) has been used to study the in situ thermal decomposition products of ethyl xanthate on mineral surfaces. These products include CS 2, COS, CO 2, CH 4, SO 2, and higher molecular weight alkyl-containing species. Decomposition pathways have been proposed with some information determined from 2H- and 13C-isotope labelling experiments.

  8. Quantitation of (R)- and (S)-linalool in beer using solid phase microextraction (SPME) in combination with a stable isotope dilution assay (SIDA).

    Science.gov (United States)

    Steinhaus, Martin; Fritsch, Helge T; Schieberle, Peter

    2003-11-19

    A stable isotope dilution assay (SIDA) was developed for the quantitation of both linalool enantiomers using synthesized [2H(2)]R/S-linalool as the internal standard. For enrichment of the target compound from beer, a solid phase microextraction method (SPME) was developed. In comparison to the more time-consuming extraction/distillation cleanup of the beer samples, the results obtained by SPME/SIDA were very similar, even under nonequilibration conditions. Analysis of five different types of beer showed significant differences in the linalool concentrations, which were clearly correlated with the intensity of the hoppy aroma note as evaluated by a sensory panel. In addition, significant differences in the R/S ratios were measured in the beers. The SPME/SIDA yielded exact data independently from headspace sampling parameters, such as exposure time or ionic strength of the solution.

  9. A comparison of sample preparation methods for extracting volatile organic compounds (VOCs) from equine faeces using HS-SPME.

    Science.gov (United States)

    Hough, Rachael; Archer, Debra; Probert, Christopher

    2018-01-01

    Disturbance to the hindgut microbiota can be detrimental to equine health. Metabolomics provides a robust approach to studying the functional aspect of hindgut microorganisms. Sample preparation is an important step towards achieving optimal results in the later stages of analysis. The preparation of samples is unique depending on the technique employed and the sample matrix to be analysed. Gas chromatography mass spectrometry (GCMS) is one of the most widely used platforms for the study of metabolomics and until now an optimised method has not been developed for equine faeces. To compare a sample preparation method for extracting volatile organic compounds (VOCs) from equine faeces. Volatile organic compounds were determined by headspace solid phase microextraction gas chromatography mass spectrometry (HS-SPME-GCMS). Factors investigated were the mass of equine faeces, type of SPME fibre coating, vial volume and storage conditions. The resultant method was unique to those developed for other species. Aliquots of 1000 or 2000 mg in 10 ml or 20 ml SPME headspace were optimal. From those tested, the extraction of VOCs should ideally be performed using a divinylbenzene-carboxen-polydimethysiloxane (DVB-CAR-PDMS) SPME fibre. Storage of faeces for up to 12 months at - 80 °C shared a greater percentage of VOCs with a fresh sample than the equivalent stored at - 20 °C. An optimised method for extracting VOCs from equine faeces using HS-SPME-GCMS has been developed and will act as a standard to enable comparisons between studies. This work has also highlighted storage conditions as an important factor to consider in experimental design for faecal metabolomics studies.

  10. Headspace Solid-Phase Microextraction Analysis of Volatile Components in Phalaenopsis Nobby’s Pacific Sunset

    Directory of Open Access Journals (Sweden)

    Chih-Hsin Yeh

    2014-09-01

    Full Text Available Phalaenopsis is the most important economic crop in the Orchidaceae family. There are currently numerous beautiful and colorful Phalaenopsis flowers, but only a few species of Phalaenopsis have an aroma. This study reports the analysis volatile components present in P. Nobby’s Pacific Sunset by solid-phase microextraction (SPME coupled with gas chromatography (GC and gas chromatography/mass spectrometry (GC-MS. The results show that the optimal extraction conditions were obtained by using a DVB/CAR/PDMS fiber. A total of 31 compounds were identified, with the major compounds being geraniol, linalool and α-farnesene. P. Nobby’s Pacific Sunset had the highest odor concentration from 09:00 to 13:00 on the eighth day of storage. It was also found that in P. Nobby’s Pacific Sunset orchids the dorsal sepals and petals had the highest odor concentrations, whereas the column had the lowest.

  11. Headspace solid phase microextraction (HSSPME) for the determination of volatile and semivolatile pollutants in soils

    Energy Technology Data Exchange (ETDEWEB)

    Llompart, Maria [Departamento de Quimica Analitica Nutricion y Bromatologia, Facultad de Quimica, Universidad de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Li, Ken; Fingas, Merv [Emergencies Science Division, Environment Canada, Environmental Technology Centre, 3439 River Road, Ottawa, ON (Canada)

    1999-02-08

    We have investigated the use of headspace solid phase microextraction (HSSPME) as a sample concentration and preparation technique for the analysis of volatile and semivolatile pollutants in soil samples. Soil samples were suspended in solvent and the SPME fibre suspended in the headspace above the slurry. Finally, the fibre was desorbed in the Gas Chromatograph (GC) injection port and the analysis of the samples was carried out. Since the transfer of contaminants from the soil to the SPME fibre involves four separate phases (soil-solvent-headspace and fibre coating), parameters affecting the distribution of the analytes were investigated. Using a well-aged artificially spiked garden soil, different solvents (both organic and aqueous) were used to enhance the release of the contaminants from the solid matrix to the headspace. It was found that simple addition of water is adequate for the purpose of analysing the target volatile organic chemicals (VOCs) in soil. The addition of 1 ml of water to 1 g of soil yielded maximum response. Without water addition, the target VOCs were almost not released from the matrix and a poor response was observed. The effect of headspace volume on response as well as the addition of salt were also investigated. Comparison studies between conventional static headspace (HS) at high temperature (95C) and the new technology HSSPME at room temperature (=20C) were performed. The results obtained with both techniques were in good agreement. HSSPME precision and linearity were found to be better than automated headspace method and HSSPME also produced a significant enhancement in response. The detection and quantification limits for the target VOCs in soils were in the sub-ng g{sup -1} level. Finally, we tried to extend the applicability of the method to the analysis of semivolatiles. For these studies, two natural soils contaminated with diesel fuel and wood preservative, as well as a standard urban dust contaminated with polyaromatic

  12. Grains colonised by moulds: fungal identification and headspace analysis of produced volatile metabolites

    Directory of Open Access Journals (Sweden)

    Maria Paola Tampieri

    2010-01-01

    Full Text Available The aim of this work was to verify if the headspace analysis of fungal volatile compounds produced by some species of Fusarium can be used as a marker of mould presence on maize. Eight samples of maize (four yellow maize from North Italy and four white maize from Hungary, naturally contaminated by Fusarium and positive for the presence of fumonisins, were analyzed to detect moisture content, Aw, volatile metabolites and an enumeration of viable moulds was performed by means of a colony count technique. Headspace samples were analysed using a gas-chromatograph equipped with a capillary column TR-WAX to detect volatile metabolites of moulds. Furthermore macro and microscopic examination of the colonies was performed in order to distinguish, according to their morphology, the genera of the prevalent present moulds. Prevalent mould of eight samples was Fusarium, but other fungi, like Aspergillus, Penicillum and Mucoraceae, were observed. The metabolites produced by F.graminearum and F. moniliforme were Isobutyl-acetate, 3-Methyl-1-butanol and, only at 8 days, 3-Octanone. The incubation time can affect off flavour production in consequence of the presence of other moulds. Further studies on maize samples under different conditions are needed in order to establish the presence of moulds using the count technique and through the identification of volatile compounds.

  13. Analysis of residual toluene in food packaging via headspace extraction method using gas chromatography

    International Nuclear Information System (INIS)

    Lim, Ying Chin; Mohd Marsin Sanagi

    2008-01-01

    Polymeric materials are used in many food contact applications as packaging material. The presence of residual toluene in this food packaging material can migrate into food and thus affect the quality of food. In this study, a manual headspace analysis was successfully designed and developed. The determination of residual toluene was carried out with standard addition method and multiple headspace extraction, MHE) method using gas chromatography-flame ionization detector, GC-FID). Identification of toluene was performed by comparison of its retention time with standard toluene and GC-MS. It was found that the suitable heating temperature was 180 degree Celsius with an optimum heating time of 10 minutes. The study also found that the concentration of residual toluene in multicolored sample was higher compared to mono colored sample whereas residual toluene in sample analyzed using standard addition method was higher compared to MHE method. However, comparison with the results obtained from De Paris laboratory, France found that MHE method gave higher accuracy for sample with low analyte concentration. On the other hand, lower accuracy was obtained for sample with high concentration of residual toluene due to systematic errors. Comparison between determination methods showed that MHE method is more precise compared to standard addition method. (author)

  14. Quantitative Analysis of Bioactive Compounds from Aromatic Plants by Means of Dynamic Headspace Extraction and Multiple Headspace Extraction-Gas Chromatography-Mass Spectrometry

    NARCIS (Netherlands)

    Omar, Jone; Olivares, Maitane; Alonso, Ibone; Vallejo, Asier; Aizpurua-Olaizola, Oier; Etxebarria, Nestor

    2016-01-01

    Seven monoterpenes in 4 aromatic plants (sage, cardamom, lavender, and rosemary) were quantified in liquid extracts and directly in solid samples by means of dynamic headspace-gas chromatography-mass spectrometry (DHS-GC-MS) and multiple headspace extraction-gas chromatography-mass spectrometry

  15. A quantitative approach for pesticide analysis in grape juice by direct interfacing of a matrix compatible SPME phase to dielectric barrier discharge ionization-mass spectrometry.

    Science.gov (United States)

    Mirabelli, Mario F; Gionfriddo, Emanuela; Pawliszyn, Janusz; Zenobi, Renato

    2018-02-12

    We evaluated the performance of a dielectric barrier discharge ionization (DBDI) source for pesticide analysis in grape juice, a fairly complex matrix due to the high content of sugars (≈20% w/w) and pigments. A fast sample preparation method based on direct immersion solid-phase microextraction (SPME) was developed, and novel matrix compatible SPME fibers were used to reduce in-source matrix suppression effects. A high resolution LTQ Orbitrap mass spectrometer allowed for rapid quantification in full scan mode. This direct SPME-DBDI-MS approach was proven to be effective for the rapid and direct analysis of complex sample matrices, with limits of detection in the parts-per-trillion (ppt) range and inter- and intra-day precision below 30% relative standard deviation (RSD) for samples spiked at 1, 10 and 10 ng ml -1 , with overall performance comparable or even superior to existing chromatographic approaches.

  16. Uncertainty of Blood Alcohol Concentration (BAC Results as Related to Instrumental Conditions: Optimization and Robustness of BAC Analysis Headspace Parameters

    Directory of Open Access Journals (Sweden)

    Haleigh A. Boswell

    2015-12-01

    Full Text Available Analysis of blood alcohol concentration is a routine analysis performed in many forensic laboratories. This analysis commonly utilizes static headspace sampling, followed by gas chromatography combined with flame ionization detection (GC-FID. Studies have shown several “optimal” methods for instrumental operating conditions, which are intended to yield accurate and precise data. Given that different instruments, sampling methods, application specific columns and parameters are often utilized, it is much less common to find information on the robustness of these reported conditions. A major problem can arise when these “optimal” conditions may not also be robust, thus producing data with higher than desired uncertainty or potentially inaccurate results. The goal of this research was to incorporate the principles of quality by design (QBD in the adjustment and determination of BAC (blood alcohol concentration instrumental headspace parameters, thereby ensuring that minor instrumental variations, which occur as a matter of normal work, do not appreciably affect the final results of this analysis. This study discusses both the QBD principles as well as the results of the experiments, which allow for determination of more favorable instrumental headspace conditions. Additionally, method detection limits will also be reported in order to determine a reporting threshold and the degree of uncertainty at the common threshold value of 0.08 g/dL. Furthermore, the comparison of two internal standards, n-propanol and t-butanol, will be investigated. The study showed that an altered parameter of 85 °C headspace oven temperature and 15 psi headspace vial pressurization produces the lowest percent relative standard deviation of 1.3% when t-butanol is implemented as an internal standard, at least for one very common platform. The study also showed that an altered parameter of 100 °C headspace oven temperature and 15-psi headspace vial pressurization

  17. Development and validation of automatic HS-SPME with a gas chromatography-ion trap/mass spectrometry method for analysis of volatiles in wines.

    Science.gov (United States)

    Paula Barros, Elisabete; Moreira, Nathalie; Elias Pereira, Giuliano; Leite, Selma Gomes Ferreira; Moraes Rezende, Claudia; Guedes de Pinho, Paula

    2012-11-15

    An automated headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed in order to quantify a large number of volatile compounds in wines such as alcohols, ester, norisoprenoids and terpenes. The procedures were optimized for SPME fiber selection, pre-incubation temperature and time, extraction temperature and time, and salt addition. A central composite experimental design was used in the optimization of the extraction conditions. The volatile compounds showed optimal extraction using a DVB/CAR/PDMS fiber, incubation of 5 ml of wine with 2g NaCl at 45 °C during 5 min, and subsequent extraction of 30 min at the same temperature. The method allowed the identification of 64 volatile compounds. Afterwards, the method was validated successfully for the most significant compounds and was applied to study the volatile composition of different white wines. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Passive Sampling and Analysis of Naphthalene in Internal Combustion Engine Exhaust with Retracted SPME Device and GC-MS

    Directory of Open Access Journals (Sweden)

    Nassiba Baimatova

    2017-07-01

    Full Text Available Exhaust gases from internal combustion engines are the main source of urban air pollution. Quantification of Polycyclic aromatic hydrocarbons (PAHs in the exhaust gases is needed for emissions monitoring, enforcement, development, and testing of control technologies. The objective was to develop quantification of gaseous naphthalene in diesel engine exhaust based on diffusion-controlled extraction onto a retracted solid-phase microextraction (SPME fiber coating and analysis on gas chromatography-mass spectrometry (GC-MS. Extraction of naphthalene with retracted fibers followed Fick’s law of diffusion. Extracted mass of naphthalene was proportional to Cg, t, Dg, T and inversely proportional to Z. Method detection limit (p = 0.95 was 11.5 ppb (0.06 mg·m−3 at t = 9 h, Z = 10 mm and T = 40 °C, respectively. It was found that the % mass extracted of naphthalene by SPME needle assembly depended on the type of fiber. Storage time at different temperatures did not affect analyte losses extracted by polydimethylsiloxane (PDMS 100 µm fiber. The developed method was tested on exhaust gases from idling pickup truck and tractor, and compared side-by-side with a direct injection of sampled exhaust gas method. Time-weighted average (TWA concentrations of naphthalene in exhaust gases from idling pickup truck and a tractor ranged from 0.08 to 0.3 mg·m−3 (15.3–53.7 ppb.

  19. Bromination of Aromatic Compounds by Residual Bromide in Sodium Chloride Matrix Modifier Salt During Heated Headspace GC/MS Analysis

    Science.gov (United States)

    Analytical artifacts attributed to the bromination of toluene, xylenes, and trimethylbenzenes were found during the heated headspace gas chromatography/mass spectrometry (GC/MS) analysis of aqueous samples. The aqueous samples were produced from Fenton-like chemical oxidation rea...

  20. Multiple headspace-solid-phase microextraction: An application to quantification of mushroom volatiles

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Rosaria; Tedone, Laura; De Grazia, Selenia [Dipartimento Farmaco-chimico, University of Messina, viale Annunziata, 98168 Messina (Italy); Dugo, Paola [Dipartimento Farmaco-chimico, University of Messina, viale Annunziata, 98168 Messina (Italy); Centro Integrato di Ricerca (C.I.R.), Università Campus-Biomedico, Via Álvaro del Portillo, 21, 00128 Roma (Italy); Mondello, Luigi, E-mail: lmondello@unime.it [Dipartimento Farmaco-chimico, University of Messina, viale Annunziata, 98168 Messina (Italy); Centro Integrato di Ricerca (C.I.R.), Università Campus-Biomedico, Via Álvaro del Portillo, 21, 00128 Roma (Italy)

    2013-04-03

    Highlights: ► Multiple headspace extraction-solid phase microextraction (MHS-SPME) has been applied to the analysis of Agaricus bisporus. ► Mushroom flavor is characterized by the presence of compounds with a 8-carbon atoms skeleton. ► Formation of 8-carbon compounds involves a unique fungal biochemical pathway. ► The MHS-SPME allowed to determine quantitatively 5 target analytes of A. bisporus for the first time. -- Abstract: Multiple headspace-solid phase microextraction (MHS-SPME) followed by gas chromatography/mass spectrometry (GC–MS) and flame ionization detection (GC–FID) was applied to the identification and quantification of volatiles released by the mushroom Agaricus bisporus, also known as champignon. MHS-SPME allows to perform quantitative analysis of volatiles from solid matrices, free of matrix interferences. Samples analyzed were fresh mushrooms (chopped and homogenized) and mushroom-containing food dressings. 1-Octen-3-ol, 3-octanol, 3-octanone, 1-octen-3-one and benzaldehyde were common constituents of the samples analyzed. Method performance has been tested through the evaluation of limit of detection (LoD, range 0.033–0.078 ng), limit of quantification (LoQ, range 0.111–0.259 ng) and analyte recovery (92.3–108.5%). The results obtained showed quantitative differences among the samples, which can be attributed to critical factors, such as the degree of cell damage upon sample preparation, that are here discussed. Considerations on the mushrooms biochemistry and on the basic principles of MHS analysis are also presented.

  1. Multiple headspace-solid-phase microextraction: An application to quantification of mushroom volatiles

    International Nuclear Information System (INIS)

    Costa, Rosaria; Tedone, Laura; De Grazia, Selenia; Dugo, Paola; Mondello, Luigi

    2013-01-01

    Highlights: ► Multiple headspace extraction-solid phase microextraction (MHS-SPME) has been applied to the analysis of Agaricus bisporus. ► Mushroom flavor is characterized by the presence of compounds with a 8-carbon atoms skeleton. ► Formation of 8-carbon compounds involves a unique fungal biochemical pathway. ► The MHS-SPME allowed to determine quantitatively 5 target analytes of A. bisporus for the first time. -- Abstract: Multiple headspace-solid phase microextraction (MHS-SPME) followed by gas chromatography/mass spectrometry (GC–MS) and flame ionization detection (GC–FID) was applied to the identification and quantification of volatiles released by the mushroom Agaricus bisporus, also known as champignon. MHS-SPME allows to perform quantitative analysis of volatiles from solid matrices, free of matrix interferences. Samples analyzed were fresh mushrooms (chopped and homogenized) and mushroom-containing food dressings. 1-Octen-3-ol, 3-octanol, 3-octanone, 1-octen-3-one and benzaldehyde were common constituents of the samples analyzed. Method performance has been tested through the evaluation of limit of detection (LoD, range 0.033–0.078 ng), limit of quantification (LoQ, range 0.111–0.259 ng) and analyte recovery (92.3–108.5%). The results obtained showed quantitative differences among the samples, which can be attributed to critical factors, such as the degree of cell damage upon sample preparation, that are here discussed. Considerations on the mushrooms biochemistry and on the basic principles of MHS analysis are also presented

  2. Analysis of aldehydes in human exhaled breath condensates by in-tube SPME-HPLC.

    Science.gov (United States)

    Wang, ShuLing; Hu, Sheng; Xu, Hui

    2015-11-05

    In this paper, polypyrrole/graphene (PPy/G) composite coating was prepared by a facile electrochemical polymerization strategy on the inner surface of a stainless steel (SS) tube. Based on the coating tube, a novel online in-tube solid-phase microextraction -high performance liquid chromatography (IT-SPME-HPLC) was developed and applied for the extraction of aldehydes in the human exhaled breath condensates (EBC). The hybrid PPy/G nanocomposite exhibits remarkable chemical and mechanical stability, high selectivity, and satisfactory extraction performance toward aldehyde compounds. Moreover, the proposed online IT-SPME-HPLC method possesses numerous superiorities, such as time and cost saving, process simplicity, high precision and sensitivity. Some parameters related to extraction efficiency were optimized systematically. Under the optimal conditions, the recoveries of the aldehyde compounds at three spiked concentration levels varied in the range of 85%-117%. Good linearity was obtained with excellent correlation coefficients (R(2)) being larger than 0.994. The relative standard deviations (n = 5) of the method ranged from 1.8% to 11.3% and the limits of detection were between 2.3 and 3.3 nmol L(-1). The successful application of the proposed method in human EBC indicated that it is a promising approach for the determination of trace aldehyde metabolites in complex EBC samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Analysis of Organic Volatile Flavor Compounds in Fermented Stinky Tofu Using SPME with Different Fiber Coatings

    Directory of Open Access Journals (Sweden)

    Wei Guan

    2012-03-01

    Full Text Available The organic volatile flavor compounds in fermented stinky tofu (FST were studied using SPME-GC/MS. A total of 39 volatile compounds were identified, including nine esters, seven alcohols, five alkenes, four sulfides, three heterocycles, three carboxylic acids, three ketones, two aldehydes, one phenol, one amine and one ether. These compounds were determined by MS, and conformed by comparison of the retention times of the separated constituents with those of authentic samples and by comparison of retention indexes (RIs of separated constituents with the RIs reported in the literature. The predominant volatile compound in FST was indole, followed by dimethyl trisulfide, phenol, dimethyl disulfide and dimethyl tetrasulfide. In order to find a better extraction time, the extraction times was optimized for each type of SPME fiber; the results show that the best extraction time for Carboxen/PDMS is 60 min, for PDMS/DVB 30 min, for DVB/CAR/PDMS 60 min and for PDMS 75 min. Of the four fibers used in this work, Carboxen/PDMS is found to be the most suitable to extract the organic volatile flavor compounds in fermented stinky tofu.

  4. Dynamic collection and analysis of volatile organic compounds from the headspace of cell cultures.

    Science.gov (United States)

    Baranska, A; Smolinska, A; Boots, A W; Dallinga, J W; van Schooten, F J

    2015-10-15

    interactions. Measurements were performed with gas chromatography time-of-flight mass spectrometry. Multivariate data analysis allowed detection of significant altered compounds in the compared groups. We found a significant change (p  ⩽  0.001) of the composition of VOCs due to the stressing of the Caco-2 cells by H2O2. A total of ten VOCs showed either increased or decreased abundance in the headspace of the cell cultures due to the presence of the H2O2 stressor.

  5. HS-SPME AS AN EFFICIENT TOOL FOR DISCRIMINATING CHEMOTYPES OF Lippia alba (Mill. N. E. Brown

    Directory of Open Access Journals (Sweden)

    Aiêrta C. C. da Silva

    Full Text Available Lippia alba (Mill. N. E. Brown (Verbenaceae is a medicinal plant for which several biological activities are reported, such as sedative, anxiolytic, anti-ulcer, antifungal, antimicrobial, antioxidant, antispasmodic, anti-nociceptive and anti-inflammatory. It is characterized by the production of essential oils which have been used to classify the plant in different chemotypes. In the Northeast region of Brazil, the presence of three chemotypes are reported: myrcene-citral (chemotype I, limonene-citral (chemotype II and carvone-limonene (chemotype III. In this work, headspace-solid phase microextraction (HS-SPME was used on the analysis of the volatile organic compounds (VOCs of three chemotypes of L. alba from the Northeast region of Brazil, and compared to the essential oils of the plants extracted by hydrodistillation. Volatile compounds from each chemotype were more effectively differentiated when extracted by HS-SPME than by hydrodistillation.

  6. Determination of dissolved methane in natural waters using headspace analysis with cavity ring-down spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Hannah M.; Shiller, Alan M., E-mail: alan.shiller@usm.edu

    2015-01-26

    Highlights: • A method for determining low nanomolar dissolved CH{sub 4} was developed. • The methane detection utilizes cavity ring-down spectroscopy (CRDS). • Use of CRDS requires less time, materials and labor than typical of GC analysis. • Relative standard deviations of ∼4% were achieved at low nM CH{sub 4}. • Applications to seawater and river water are presented. - Abstract: Methane (CH{sub 4}) is the third most abundant greenhouse gas (GHG) but is vastly understudied in comparison to carbon dioxide. Sources and sinks to the atmosphere vary considerably in estimation, including sources such as fresh and marine water systems. A new method to determine dissolved methane concentrations in discrete water samples has been evaluated. By analyzing an equilibrated headspace using laser cavity ring-down spectroscopy (CRDS), low nanomolar dissolved methane concentrations can be determined with high reproducibility (i.e., 0.13 nM detection limit and typical 4% RSD). While CRDS instruments cost roughly twice that of gas chromatographs (GC) usually used for methane determination, the process presented herein is substantially simpler, faster, and requires fewer materials than GC methods. Typically, 70-mL water samples are equilibrated with an equivalent amount of zero air in plastic syringes. The equilibrated headspace is transferred to a clean, dry syringe and then drawn into a Picarro G2301 CRDS analyzer via the instrument’s pump. We demonstrate that this instrument holds a linear calibration into the sub-ppmv methane concentration range and holds a stable calibration for at least two years. Application of the method to shipboard dissolved methane determination in the northern Gulf of Mexico as well as river water is shown. Concentrations spanning nearly six orders of magnitude have been determined with this method.

  7. Comparison of Three Methods for Extraction of Volatile Lipid Oxidation Products from Food Matrices for GC-MS Analysis

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Yesiltas, B.; Berner, Lis

    headspace extraction has been performed manually. Recently, automated dynamic headspace methods have become available. This presentation will summarize the principles of the different extraction methods. Moreover, results from fish oil, oil-in-water emulsion and milk obtained with SPME, manual dynamic...... headspace or automated dynamic headspace (TDU/DHS) extraction followed by GC-MS analysis will be compared. In all cases, concentrations of volatiles were quantified by calibration curves by addition of selected standards to oil, emulsion or milk. The results show that the linearity of calibration curves...

  8. Comparative analysis of the vapor headspace of military-grade TNT versus NESTT TNT under dynamic and static conditions

    Science.gov (United States)

    Edge, Cindy C.; Gibb, Julie; Wasserzug, Louis S.

    1998-09-01

    The Institute for Biological Detection Systems (IBDS) has developed a quantitative vapor delivery system that can aid in characterizing dog's sensitivity and ability to recognize odor signatures for explosives and contraband substances. Determining of the dog's odor signature for detection of explosives is important because it may aid in eliminating the risk of handling explosives and reducing cross-contamination. Progress is being made in the development of training aids that represent the headspace of the explosives. NESTTTM TNT materials have been proposed as an approach to developing training aid simulates. In order for such aids to be effective they must mimic the headspace of the target material. This study evaluates the NESTTTM TNT product with regard to this criterion. NESTTTM TNT vapor was generated by the IBDS vapor delivery system, which incorporates a vapor generation cell that enables the user to control the conditions under which a substance is tested. The NESTTTM TNT vapor was compared to the headspace of military-grade TNT. The findings identify and quantify major vapor constituents of military-grade TNT and NESTTTM TNT. A comparative analysis evaluated the degree to which the NESTTTM TNT mimics the headspace of an actual TNT sample.

  9. Systematic comparison of static and dynamic headspace sampling techniques for gas chromatography.

    Science.gov (United States)

    Kremser, Andreas; Jochmann, Maik A; Schmidt, Torsten C

    2016-09-01

    Six automated, headspace-based sample preparation techniques were used to extract volatile analytes from water with the goal of establishing a systematic comparison between commonly available instrumental alternatives. To that end, these six techniques were used in conjunction with the same gas chromatography instrument for analysis of a common set of volatile organic carbon (VOC) analytes. The methods were thereby divided into three classes: static sampling (by syringe or loop), static enrichment (SPME and PAL SPME Arrow), and dynamic enrichment (ITEX and trap sampling). For PAL SPME Arrow, different sorption phase materials were also included in the evaluation. To enable an effective comparison, method detection limits (MDLs), relative standard deviations (RSDs), and extraction yields were determined and are discussed for all techniques. While static sampling techniques exhibited sufficient extraction yields (approx. 10-20 %) to be reliably used down to approx. 100 ng L(-1), enrichment techniques displayed extraction yields of up to 80 %, resulting in MDLs down to the picogram per liter range. RSDs for all techniques were below 27 %. The choice on one of the different instrumental modes of operation (aforementioned classes) was thereby the most influential parameter in terms of extraction yields and MDLs. Individual methods inside each class showed smaller deviations, and the least influences were observed when evaluating different sorption phase materials for the individual enrichment techniques. The option of selecting specialized sorption phase materials may, however, be more important when analyzing analytes with different properties such as high polarity or the capability of specific molecular interactions. Graphical Abstract PAL SPME Arrow during the extraction of volatile analytes from the headspace of an aqueous sample.

  10. HS-SPME analysis of volatile organic compounds of coniferous needle litter

    Science.gov (United States)

    Isidorov, V. A.; Vinogorova, V. T.; Rafałowski, K.

    The composition of volatile emission of Scots pine ( Pinus sylvestris) and spruce ( Picea exelsa) litter was studied by gas chromatography-mass spectrometry (GC-MS) and samples were collected by solid-phase microextraction (SPME) method. The list of identified compounds includes over 60 organic substances of different classes. It was established that volatile emission contain not only components of essential oils of pine and spruce needles but also a large number of organic compounds which are probably secondary metabolites of litter-decomposing fungi. They include lower carbonyl compounds and alcohols as well as products of terpene dehydration and oxidation. These data show that the processes of litter decomposition are an important source of reactive organic compounds under canopy of coniferous forests.

  11. SPME GC/MS determination of organochlorine pesticides in water samples

    Directory of Open Access Journals (Sweden)

    Yerbolat Sailaukhanuly

    2013-05-01

    Full Text Available Headspace solid phase microextraction (HS-SPME in combination with gas chromatography and mass-spectrometry (GC/MS was studied for analysis of water samples. The organochlorine pesticides (OCPs, p,p'-DDT, p,p'-DDD, and p,p'-DDE were collected and analyzed by GC/MS. To select of effective fiber coatings four types of SPME fibers were examined and compared. The parameters effecting the efficiency of HS-SPME such as extraction and pre-incubation time and extraction temperature, effect of solvent nature, ionic strength were studied to obtain optimal parameters. The method was developed using spiked water samples in a concentration range  10 - 500 ng/L. The calibration curve was linear over the studied concentration range with r≥0.9925. The detection limits varied from 1.57 to 2.08 ng/L. An authentic water samples from contaminated lake with OCPs were analyzed by developed method.

  12. Headspace Analysis of Philippine Civet Coffee Beans Using Gas Chromatography-Mass Spectrometry and Electronic Nose

    Science.gov (United States)

    Ongo, E.; Sevilla, F.; Antonelli, A.; Sberveglieri, G.; Montevecchi, G.; Sberveglieri, V.; de Paola, E. L.; Concina, I.; Falasconi, M.

    2011-11-01

    Civet coffee, the most expensive and best coffee in the world, is an economically important export product of the Philippines. With a growing threat of food adulteration and counterfeiting, a need for quality authentication is essential to protect the integrity and strong market value of Philippine civet coffee. At present, there is no internationally accepted method of verifying whether a bean is an authentic civet coffee. This study presented a practical and promising approach to identify and establish the headspace qualitative profile of Philippine civet coffee using electronic nose (E-nose) and gas chromatography-mass spectrometry (GC-MS). E-nose analysis revealed that aroma characteristic is one of the most important quality indicators of civet coffee. The findings were supported by GC-MS analysis. Principal component analysis (PCA) exhibited a clearly separated civet coffees from their control beans. The chromatographic fingerprints indicated that civet coffees differed with their control beans in terms of composition and concentration of individual volatile constituents.

  13. Analysis of volatile headspace gases sampled by cryogenic traps from Westinghouse Hanford Company Tank 242-C-112 March 1992

    International Nuclear Information System (INIS)

    Lucke, R.B.; Clauss, S.A.

    1993-10-01

    Results are given from gas chromatography/mass spectrometry (GC/MS) analyses of the headspace samples obtained by using cryogenic traps from Westinghouse Hanford Company (WHC) Tank 112-C during the month of March, 1992. Samples were analyzed as received with no sample preparation. Analyses included direct GC/MS for volatile/semivolatile components, and direct GC/MS for ammonia. Purge and trap GC/MS analysis was not done. In addition, aliquots were sent to Karl Pool, Pacific Northwest Laboratory, for hydrogen cyanide analysis by ion chromatography, the results are reported here. All concentrations are reported for the methanol extract solutions. To calculate concentrations in the headspace, the cryo-sampling air volume and the methanol rinse volume must be obtained from cryo-sampling personnel at WHC. Triplicate analyses were done on all samples, and average concentrations and standard deviations are reported. One significant result was that no ammonia was detected

  14. Field portable low temperature porous layer open tubular cryoadsorption headspace sampling and analysis part I: Instrumentation.

    Science.gov (United States)

    Bruno, Thomas J

    2016-01-15

    Building on the successful application in the laboratory of PLOT-cryoadsorption as a means of collecting vapor (or headspace) samples for chromatographic analysis, in this paper a field portable apparatus is introduced. This device fits inside of a briefcase (aluminum tool carrier), and can be easily transported by vehicle or by air. The portable apparatus functions entirely on compressed air, making it suitable for use in locations lacking electrical power, and for use in flammable and explosive environments. The apparatus consists of four aspects: a field capable PLOT-capillary platform, the supporting equipment platform, the service interface between the PLOT-capillary and the supporting equipment, and the necessary peripherals. Vapor sampling can be done with either a hand piece (containing the PLOT capillary) or with a custom fabricated standoff module. Both the hand piece and the standoff module can be heated and cooled to facilitate vapor collection and subsequent vapor sample removal. The service interface between the support platform and the sampling units makes use of a unique counter current approach that minimizes loss of cooling and heating due to heat transfer with the surroundings (recuperative thermostatting). Several types of PLOT-capillary elements and sampling probes are described in this report. Applications to a variety of samples relevant to forensic and environmental analysis are discussed in a companion paper. Published by Elsevier B.V.

  15. Establishment of Exposure to Organophosphorus Warfare Agents by Means of SPME-GSMS Analysis of Bodily Fluids

    International Nuclear Information System (INIS)

    Saveleva, E. I.; Koryagina, N. L.; Radilov, A. S.; Khlebnikova, N. S.; Khrustaleva, V. S.; Feld, V. E.

    2007-01-01

    Reliable chemical analytical procedures for revealing an exposure to toxic chemicals, identifying the active substance, and assessing the degree of exposure are necessary as a component of medical and forensic activities in cases of the possible use of highly toxic chemicals in war conflicts and terrorism acts, as well as emergency situations in chemical industry, specifically at chemical weapons storage and destruction facilities. According to Chemical Weapons Convention, Part XI, Appendix 4, e-17, 'samples of importance in the investigation of alleged use include biomedical samples from human or animal sources (blood, urine, excreta, tissue etc.)'. Urinary metabolites, O-alkyl esters of methylphosphic acid, offer one of the simplest means of confirming an exposure to organophosphorus warfare agents (OPWA). Urine, unlike blood or tissues, does not require invasive collection demanding in terms of sterility. Excretion with urine is the major route of elimination of OPWA from an organism. According to published data, 90% of OPWA metabolites are excreted within 48-72 h after intoxication. We developed an SPME-GCMS procedure for the determination of O-alkyl esters methylphosphonic acid in urine, with the following detection limits,: isopropyl and isobutyl esters 5 ng/ml and pinacolyl ester 1 ng/ml. The procedure involves derivatization of the target compounds directly on the microfiber. The total analysis time is 1-1.5 h. In animal experiments in vivo we could establish the exposure to OPWA at a half-LD50 level within no less than 48 h after intoxication. In principle, OPWA metabolites could be detected in urine within two weeks after intoxication but at higher doses. Retrospective analysis of urinary metabolites in cases of the exposure to low doses of OPWA requires lower detection limits (0.1-1 ng/ml). Optimal objects for the retrospective analysis of OPWA in an organism are long-lived blood protein adducts. We developed a procedure for revealing an exposure to

  16. Neuro-genetic multioptimization of the determination of polychlorinated biphenyl congeners in human milk by headspace solid phase microextraction coupled to gas chromatography with electron capture detection

    International Nuclear Information System (INIS)

    Hoffmann Kowalski, Claudia; Silva, Gilmare Antonia da; Poppi, Ronei Jesus; Teixeira Godoy, Helena; Augusto, Fabio

    2007-01-01

    Polychlorinated biphenyls (PCB) can eventually contaminate breast milk, which is a serious issue to the newborn due to their high vulnerability. Solid phase microextraction (SPME) can be a very convenient technique for their isolation and pre-concentration prior chromatographic analysis. Here, a simultaneous multioptimization strategy based on a neuro-genetic approach was applied to a headspace SPME method for determination of 12 PCB in human milk. Gas chromatography with electron capture detection (ECD) was adopted for the separation and detection of the analytes. Experiments according to a Doehlert design were carried out with varied extraction time and temperature, media ionic strength and concentration of the methanol (co-solvent). To find the best model that simultaneously correlate all PCB peak areas and SPME extraction conditions, a multivariate calibration method based on a Bayesian Neural Network (BNN) was applied. The net output from the neural network was used as input in a genetic algorithm (GA) optimization operation (neuro-genetic approach). The GA pointed out that the best values of the overall SPME operational conditions were the saturation of the media with NaCl, extraction temperature of 95 deg. C, extraction time of 60 min and addition of 5% (v/v) methanol to the media. These optimized parameters resulted in the decrease of the detection limits and increase on the sensitivity for all tested analytes, showing that the use of neuro-genetic approach can be a promising way for optimization of SPME methods

  17. Monoterpene synthase from Dracocephalum kotschyi and SPME-GC-MS analysis of its aroma profile

    Directory of Open Access Journals (Sweden)

    S. Saeidnia

    2014-04-01

    Full Text Available Dracocephalum kotschyi (Lamiaceae, as one of the remarkable aromatic plants, widely grows and also is cultivated in various temperate regions of Iran. There are diverse reports about the composition of the oil of this plant representing limonene derivatives as its major compounds. There is no report on cloning of mono- or sesquiterpene synthases from this plant. In the present study, the aroma profile of D. kotschyi has been extracted and analyzed via Headspace Solid-Phase Microextraction technique coupled with Gas Chromatography- Mass Spectroscopy. In order to determine the sequence of the active terpene synthase in this plant, first mRNA was prepared and cloning was performed by 3’ and 5’-RACEs-PCR method, then cDNA was sequenced and finally aligned with other recognized terpene synthases. The results showed that the plant leaves mainly comprised geranial (37.2%, limonene-10-al (28.5%, limonene (20.1% and 1,1-dimethoxy decane (14.5%. Sequencing the cDNA cloned from this plant revealed the presence of a monoterpene synthase absolutely similar to limonene synthase, responsible in formation of limonene, terpinolene, camphene and some other cyclic monoterpenes in its young leaves.

  18. Method detection limit determination and application of a convenient headspace analysis method for methyl tert-butyl ether in water.

    Science.gov (United States)

    O'Neill, Dennis T; Rochette, Elizabeth A; Ramsey, Philip J

    2002-11-15

    Methyl tert-butyl ether (MTBE) is a common groundwater contaminant, introduced to the environment by leaking petroleum storage tanks, urban runoff, and motorized watercraft. In this study. a simplified (static) headspace analysis method was adapted for determination of MTBE in water samples and soil water extracts. The MDL of the headspace method was calculated to be 2.0 microg L(-1) by the EPA single-concentration design method(1) and 1.2 microg L(-1) by a calibration method developed by Hubaux and Vos (Hubaux, A.; Vos, G. Anal. Chem. 1970,42, 849-855). The MDL calculated with the Hubaux and Vos method was favored because it considers both a true positive and a false positive. The static headspace method was applied to analysis of a tap water sample and a monitoring well sample from a gasoline service station, a river sample, and aqueous extracts from soil excavated during removal of a leaking underground storage tank (LUST). The water samples examined in this study had MTTBE concentrations ranging from 6 to 19 microg L(-1). Aqueous extracts of a soil sample taken from the LUST site had 8 microg L(-1) MTBE.

  19. Optimisation and validation of a HS-SPME-GC-IT/MS method for analysis of carbonyl volatile compounds as biomarkers in human urine: Application in a pilot study to discriminate individuals with smoking habits.

    Science.gov (United States)

    Calejo, Isabel; Moreira, Nathalie; Araújo, Ana Margarida; Carvalho, Márcia; Bastos, Maria de Lourdes; de Pinho, Paula Guedes

    2016-02-01

    A new and simple analytical approach consisting of an automated headspace solid-phase microextraction (HS-SPME) sampler coupled to gas chromatography-ion trap/mass spectrometry detection (GC-IT/MS) with a prior derivatization step with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was developed to detect volatile carbonyl metabolites with low molecular weights in human urine. A central composite design (CCD) was used to optimise the PFBHA concentration and extraction conditions that affect the efficiency of the SPME procedure. With a sample volume of 1 mL, optimal conditions were achieved by adding 300 mg/L of PFBHA and allowing the sample to equilibrate for 6 min at 62°C and then extracting the samples for 51 min at the same temperature, using a divinylbenzene/polydimethylsiloxane (DVB/PDMS) fibre. The method allowed the simultaneous identification and quantification of 44 carbonyl compounds consisting of aldehydes, dialdehydes, heterocyclic aldehydes and ketones. The method was validated with regards to the linearity, inter- and intra-day precision and accuracy. The detection limits ranged from 0.009 to 0.942 ng/mL, except for 4-hydroxy-2-nonenal (15 ng/mL), and the quantification limits varied from 0.029 to 1.66 ng/mL, except for butanal (2.78 ng/mL), 2-butanone (2.67 ng/mL), 4-heptanone (3.14 ng/mL) and 4-hydroxy-2-nonenal (50.0 ng/mL). The method accuracy was satisfactory, with recoveries ranging from 90 to 107%. The proof of applicability of the methodology was performed in a pilot target analysis of urine samples obtained from 18 healthy smokers and 18 healthy non-smokers (control group). Chemometric supervised analysis was performed using the volatile patterns acquired for these samples and clearly showed the potential of the volatile carbonyl profiles to discriminate urine from smoker and non-smoker subjects. 5-Methyl-2-furfural (p<0.0001), 2-methylpropanal, nonanal and 2-methylbutanal (p<0.05) were identified as potentially useful

  20. Second Order Kinetic Modeling of Headspace Solid Phase Microextraction of Flavors Released from Selected Food Model Systems

    Directory of Open Access Journals (Sweden)

    Jiyuan Zhang

    2014-09-01

    Full Text Available The application of headspace-solid phase microextraction (HS-SPME has been widely used in various fields as a simple and versatile method, yet challenging in quantification. In order to improve the reproducibility in quantification, a mathematical model with its root in psychological modeling and chemical reactor modeling was developed, describing the kinetic behavior of aroma active compounds extracted by SPME from two different food model systems, i.e., a semi-solid food and a liquid food. The model accounted for both adsorption and release of the analytes from SPME fiber, which occurred simultaneously but were counter-directed. The model had four parameters and their estimated values were found to be more reproducible than the direct measurement of the compounds themselves by instrumental analysis. With the relative standard deviations (RSD of each parameter less than 5% and root mean square error (RMSE less than 0.15, the model was proved to be a robust one in estimating the release of a wide range of low molecular weight acetates at three environmental temperatures i.e., 30, 40 and 60 °C. More insights of SPME behavior regarding the small molecule analytes were also obtained through the kinetic parameters and the model itself.

  1. Volatile Hydrocarbon Analysis in Blood by Headspace Solid-Phase Microextraction: The Interpretation of VHC Patterns in Fire-Related Incidents.

    Science.gov (United States)

    Waters, Brian; Hara, Kenji; Ikematsu, Natsuki; Takayama, Mio; Kashiwagi, Masayuki; Matsusue, Aya; Kubo, Shin-Ichi

    2017-05-01

    A headspace solid-phase microextraction (HS-SPME) technique was used to quantitate the concentration of volatile hydrocarbons from the blood of cadavers by cryogenic gas chromatography-mass spectroscopy. A total of 24 compounds including aromatic and aliphatic volatile hydrocarbons were analyzed by this method. The analytes in the headspace of 0.1 g of blood mixed with 1.0 mL of distilled water plus 1 µL of an internal standard solution were adsorbed onto a 100-µm polydimethylsiloxane fiber at 0°C for 15 min, and measured using a GC-MS full scan method. The limit of quantitation for the analytes ranged from 6.8 to 10 ng per 1 g of blood. This method was applied to actual autopsy cases to quantitate the level of volatile hydrocarbons (VHCs) in the blood of cadavers who died in fire-related incidents. The patterns of the VHCs revealed the presence or absence of accelerants. Petroleum-based fuels such as gasoline and kerosene were differentiated. The detection of C8-C13 aliphatic hydrocarbons indicated the presence of kerosene; the detection of C3 alkylbenzenes in the absence of C8-C13 aliphatic hydrocarbons was indicative of gasoline; and elevated levels of styrene or benzene in the absence of C3/C4 alkylbenzenes and aliphatic hydrocarbons indicated a normal construction fire. This sensitive HS-SPME method could help aid the investigation of fire-related deaths by providing a simple pattern to use for the interpretation of VHCs in human blood. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Quantitative analysis of 2-furfural and 5-methylfurfural in different Italian vinegars by headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry using isotope dilution.

    Science.gov (United States)

    Giordano, Lucia; Calabrese, Roberto; Davoli, Enrico; Rotilio, Domenico

    2003-10-31

    A new method was developed for the determination of 2-furfural (2-F) and 5-methylfurfural (5-MF), two products of Maillard reaction in vinegar, with head-space solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). A divinylbenzene (DVB)/carboxen (CAR)/polydimethylsiloxane (PDMS) fibre was used and SPME conditions were optimised, studying ionic strength effect, temperature effect and adsorption time. Both analytes were determined by calibration established on 2-furfural-d4 (2-F-d4). The method showed good linearity in the range studied (from 16 to 0.12 mg/l), with a regression coefficient r2 of 0.9999. Inter-batch precision and accuracy were found between 14.9 and 6.0% and between -11.7 and 0.2%, respectively. Detection limit was 15 microg/l. The method is simple and accurate and it has been applied to a series of balsamic and non-balsamic vinegars.

  3. Comparison of common components analysis with principal components analysis and independent components analysis: Application to SPME-GC-MS volatolomic signatures.

    Science.gov (United States)

    Bouhlel, Jihéne; Jouan-Rimbaud Bouveresse, Delphine; Abouelkaram, Said; Baéza, Elisabeth; Jondreville, Catherine; Travel, Angélique; Ratel, Jérémy; Engel, Erwan; Rutledge, Douglas N

    2018-02-01

    The aim of this work is to compare a novel exploratory chemometrics method, Common Components Analysis (CCA), with Principal Components Analysis (PCA) and Independent Components Analysis (ICA). CCA consists in adapting the multi-block statistical method known as Common Components and Specific Weights Analysis (CCSWA or ComDim) by applying it to a single data matrix, with one variable per block. As an application, the three methods were applied to SPME-GC-MS volatolomic signatures of livers in an attempt to reveal volatile organic compounds (VOCs) markers of chicken exposure to different types of micropollutants. An application of CCA to the initial SPME-GC-MS data revealed a drift in the sample Scores along CC2, as a function of injection order, probably resulting from time-related evolution in the instrument. This drift was eliminated by orthogonalization of the data set with respect to CC2, and the resulting data are used as the orthogonalized data input into each of the three methods. Since the first step in CCA is to norm-scale all the variables, preliminary data scaling has no effect on the results, so that CCA was applied only to orthogonalized SPME-GC-MS data, while, PCA and ICA were applied to the "orthogonalized", "orthogonalized and Pareto-scaled", and "orthogonalized and autoscaled" data. The comparison showed that PCA results were highly dependent on the scaling of variables, contrary to ICA where the data scaling did not have a strong influence. Nevertheless, for both PCA and ICA the clearest separations of exposed groups were obtained after autoscaling of variables. The main part of this work was to compare the CCA results using the orthogonalized data with those obtained with PCA and ICA applied to orthogonalized and autoscaled variables. The clearest separations of exposed chicken groups were obtained by CCA. CCA Loadings also clearly identified the variables contributing most to the Common Components giving separations. The PCA Loadings did not

  4. Rapid and sensitive analysis of polychlorinated biphenyls and acrylamide in food samples using ionic liquid-based in situ dispersive liquid-liquid microextraction coupled to headspace gas chromatography.

    Science.gov (United States)

    Zhang, Cheng; Cagliero, Cecilia; Pierson, Stephen A; Anderson, Jared L

    2017-01-20

    A simple and rapid ionic liquid (IL)-based in situ dispersive liquid-liquid microextraction (DLLME) method was developed and coupled to headspace gas chromatography (HS-GC) employing electron capture (ECD) and mass spectrometry (MS) detection for the analysis of polychlorinated biphenyls (PCBs) and acrylamide at trace levels from milk and coffee samples. The chemical structures of the halide-based ILs were tailored by introducing various functional groups to the cations to evaluate the effect of different structural features on the extraction efficiency of the target analytes. Extraction parameters including the molar ratio of IL to metathesis reagent and IL mass were optimized. The effects of HS oven temperature and the HS sample vial volume on the analyte response were also evaluated. The optimized in situ DLLME method exhibited good analytical precision, good linearity, and provided detection limits down to the low ppt level for PCBs and the low ppb level for acrylamide in aqueous samples. The matrix-compatibility of the developed method was also established by quantifying acrylamide in brewed coffee samples. This method is much simpler and faster compared to previously reported GC-MS methods using solid-phase microextraction (SPME) for the extraction/preconcentration of PCBs and acrylamide from complex food samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Ultra trace analysis of PAHs by designing simple injection of large amounts of analytes through the sample reconcentration on SPME fiber after magnetic solid phase extraction.

    Science.gov (United States)

    Khodaee, Nader; Mehdinia, Ali; Esfandiarnejad, Reyhaneh; Jabbari, Ali

    2016-01-15

    A simple solventless injection method was introduced based on the using of a solid-phase microextraction (SPME) fiber for injection of large amounts of the analytes extracted by the magnetic solid phase extraction (MSPE) procedure. The resulted extract from MSPE procedure was loaded on a G-coated SPME fiber, and then the fiber was injected into the gas chromatography (GC) injection port. This method combines the advantages of exhaustive extraction property of MSPE and the solvent-less injection of SPME to improve the sensitivity of the analysis. In addition, the analytes were re-concentrated prior to inject into the gas chromatography (GC) inlet because of the organic solvent removing from the remaining extract of MSPE technique. Injection of the large amounts of analytes was made possible by using the introduced procedure. Fourteen polycyclic aromatic hydrocarbons (PAHs) with different volatility were used as model compounds to investigate the method performance for volatile and semi-volatile compounds. The introduced method resulted in the higher enhancement factors (5097-59376), lower detection limits (0.29-3.3pgmL(-1)), and higher sensitivity for the semi-volatile compounds compared with the conventional direct injection method. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Analysis of High Quality Agar wood Oil Chemical Compounds By Means Of SPME/ GC-MS and Z-Score Technique

    International Nuclear Information System (INIS)

    Nurlaila Ismail; Mohd Ali Nor Azah; Mailina Jamil; Saiful Nizam Tajuddin; Mohd Nasir Taib

    2013-01-01

    Currently, the grading of the agar wood oil to the high and low quality is done using manually such as human trained grader. It was performed based on the agar wood oil physical properties such as human experience and perception and the oil colour, odor and long lasting aroma. Several researchers found that chemical profiles of the oil should be utilized to overcome the problem facing by manual techniques for example human nose cannot tolerate with the many oils at the same time, so that accurate result can be obtained in grading the agar wood oil. The analysis involved of SPME/ GC-MS and Z-score techniques have been proposed in this study to analyze the chemical compounds especially from the high quality samples of agar wood oil (Aquilariamalaccensis) from Malaysia. Two SPME fibers were used such as divinylbenzene-carbogen-polydimethylsiloxane (DVB-CAR-PDMS) and polydimethylsiloxane (PDMS) in extracting the oils compound under three different sampling temperature conditions such as 40, 60 and 80 degree Celsius. The chemical compounds extracted by SPME/ GC-MS were analyzed. The chemical compounds as identified by Z-score as significant compounds were discussed before the conclusion is made. It was found that 10-epi-γ-eudesmol, aromadendrene, β-agar ofuran, α-agar ofuran and γ-eudesmol were highlighted as significant for high quality agar wood oil and can be used as a marker compounds in classifying the agar wood oil. (author)

  7. Essential oil from Rhaponticum acaule L. roots: Comparative study using HS-SPME/GC/GC–MS and hydrodistillation techniques

    Directory of Open Access Journals (Sweden)

    Batoul Benyelles

    2014-12-01

    Full Text Available The composition of essential oil extracted from Rhaponticum acaule L. roots growing wild in Algeria was studied by hydrodistillation (HD and by Head-Space Solid Phase Micro-Extraction (HS-SPME. Quantitative but not qualitative differences have been found in the chemical composition of both analysed samples depending on the extraction method. However, the oil obtained from R. acaule roots shows that aliphatic alcohols were found to be the major class (69.2%, followed by the terpenes (5.5%, alkenes (5.2% and alkynes (4.0%. In both cases the analysis were carried out using Gas Chromatography (GC and Gas Chromatography–Mass Spectrometry (GC–MS. Our study shows that HS-SPME extraction could be considered as an alternative technique for the isolation of volatiles from plant. 25 components were identified in oil vs. 39 in the HS-SPME. However the oil composition of roots was mainly represented by a variety of aliphatic hydrocarbons (alcohols, aldehydes and ketones and terpenes which are known for their antimicrobial activities.

  8. Uptake of Radionuclide Metals by SPME Fibers

    International Nuclear Information System (INIS)

    Duff, M; S Crump, S; Robert Ray, R; Keisha Martin, K; Donna Beals, D

    2006-08-01

    The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) and fire debris (FD) evidence while maintaining evidentiary value. One experimental method for the isolation of HE and FD residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolved radionuclide ( 239/240 Pu, 238 U, 237 Np, 85 Sr, 133 Ba, 137 Cs, 60 Co and 226 Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE and FD residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE and FD residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection

  9. Speciation of mercury compounds by gas chromatography with atomic emission detection. Simultaneous optimization of a headspace solid-phase microextraction and derivatization procedure by use of chemometric techniques

    Energy Technology Data Exchange (ETDEWEB)

    Carro, A.M.; Neira, I.; Rodil, R.; Lorenzo, R. A. [Univ. Santiago de Compostela (Spain). Dpto. Quimica Analitica, Nutricion y Bromatologia

    2003-06-01

    A method is proposed for the extraction and determination of organomercury compounds and Hg(II) in seawater samples by headspace solid-phase microextraction (HS-SPME) combined with capillary gas chromatography-microwave-induced plasma atomic emission spectrometry. The mercury species were derivatized with sodium tetraphenylborate, sorbed on a polydimethylsiloxane-coated fused-silica fibre, and desorbed in the injection port of the GC, in splitless mode. Experimental design methodology was used to evaluate the effect of six HS-SPME-derivatization variables: sample volume, NaBPh{sub 4} volume, pH, sorption time, extraction-derivatization temperature, and rate of stirring. Use of a multicriterion decision-making approach, with the desirability function, enabled determination of the optimum working conditions of the procedure for simultaneous analysis of three mercury species. (orig.)

  10. pH-dependent equilibrium isotope fractionation associated with the compound specific nitrogen and carbon isotope analysis of substituted anilines by SPME-GC/IRMS.

    Science.gov (United States)

    Skarpeli-Liati, Marita; Turgeon, Aurora; Garr, Ashley N; Arnold, William A; Cramer, Christopher J; Hofstetter, Thomas B

    2011-03-01

    Solid-phase microextraction (SPME) coupled to gas chromatography/isotope ratio mass spectrometry (GC/IRMS) was used to elucidate the effects of N-atom protonation on the analysis of N and C isotope signatures of selected aromatic amines. Precise and accurate isotope ratios were measured using polydimethylsiloxane/divinylbenzene (PDMS/DVB) as the SPME fiber material at solution pH-values that exceeded the pK(a) of the substituted aniline's conjugate acid by two pH-units. Deviations of δ(15)N and δ(13)C-values from reference measurements by elemental analyzer IRMS were small (IRMS. Under these conditions, the detection limits for accurate isotope ratio measurements were between 0.64 and 2.1 mg L(-1) for δ(15)N and between 0.13 and 0.54 mg L(-1) for δ(13)C, respectively. Substantial inverse N isotope fractionation was observed by SPME-GC/IRMS as the fraction of protonated species increased with decreasing pH leading to deviations of -20‰ while the corresponding δ(13)C-values were largely invariant. From isotope ratio analysis at different solution pHs and theoretical calculations by density functional theory, we derived equilibrium isotope effects, EIEs, pertinent to aromatic amine protonation of 0.980 and 1.001 for N and C, respectively, which were very similar for all compounds investigated. Our work shows that N-atom protonation can compromise accurate compound-specific N isotope analysis of aromatic amines.

  11. Analysis of benzene, toluene, ethylbenzene and xylenes in soils by headspace and gas chromatography/flame ionization detector

    Directory of Open Access Journals (Sweden)

    Jurandir Pereira Pinto

    2006-02-01

    Full Text Available The constituents of gasoline: benzene, toluene, ethylbenzene and xylenes (BTEX are frequently found in soils due to leaks in fuel storage tanks and they present chronic toxicity. In this work it was developed and validated a methodology of BTEX analysis in soil by gas chromatography/ flame ionization detector and static headspace. The recovery of BTEX in soil samples was evaluated using soils with different textures (sandy and loamy. The analysis method showed good resolution, in a low time of analysis (less than 30 minutes. Limits of quantification of 0.05 mg Kg¯¹ soil for benzene, toluene, ethylbenzene and xylenes are below the guiding values that range from 0.15 to 95 mg Kg¯¹ soil, established to determine soil quality. It was verified that the methodology enables the use of this method for BTEX analysis of soil samples for passive environmental identification of gas stations.

  12. Determination of fatty acids and volatile compounds in fruits of rosehip(Rosa L.) species by HS-SPME/GC-MS and Im-SPME/GC-MS techniques

    OpenAIRE

    MURATHAN, ZEHRA TUĞBA; ZARIFIKHOSROSHAHI, MOZGAN; KAFKAS, NESİBE EBRU

    2016-01-01

    In this study, we aimed to compare fatty acid and volatile compound compositions of four rosehip species, namely Rosa pimpinellifolia, R. Villosa, R. Canina, and R. Dumalis, by gas chromatography with flame ionization detector (GC/FID) and headspace and immersion solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME/GC-MS and Im-SPME/GC-MS) techniques. The total lipid contents in fruits of the rosehip species varied from 5.83% (R. Villosa) to 7.84% (R. Dumalis). A total of...

  13. SOLID PHASE MICRO EXTRACTION (SPME) FLAVOR ANALYSIS OF APPLE JUICE AND COFFEE MIXTURES USING GAS CHROMATOGRAPHY-MASS SPECTROMETRY (GC-MS)

    OpenAIRE

    Mi Ja Kim; Jeehyun Lee; Jaeyoung Byun; Sunmi Choi; Wonsik Choi

    2016-01-01

    This research was conducted to evaluate the flavor of apple juice and coffee mixtures and the sensory quality of SPME extracts using gas chromatography-mass spectrometry (GC-MS). Three samples with different compositions were examined. Sample A1 contained85% apple juiceand 15% coffee, sample A2 had87.5% apple and 12.5% coffee, and sample A3 had90% apple juiceand 10% coffee. The sensory analysis involved 100 panelists and a sequential monadic test. Sample presentation orders were balanced in ...

  14. Determination of Porosity in Shale by Double Headspace Extraction GC Analysis.

    Science.gov (United States)

    Zhang, Chun-Yun; Li, Teng-Fei; Chai, Xin-Sheng; Xiao, Xian-Ming; Barnes, Donald

    2015-11-03

    This paper reports on a novel method for the rapid determination of the shale porosity by double headspace extraction gas chromatography (DHE-GC). Ground core samples of shale were placed into headspace vials and DHE-GC measurements of released methane gas were performed at a given time interval. A linear correlation between shale porosity and the ratio of consecutive GC signals was established both theoretically and experimentally by comparing with the results from the standard helium pycnometry method. The results showed that (a) the porosity of ground core samples of shale can be measured within 30 min; (b) the new method is not significantly affected by particle size of the sample; (c) the uncertainties of measured porosities of nine shale samples by the present method range from 0.31 to 0.46 p.u.; and (d) the results obtained by the DHE-GC method are in a good agreement with those from the standard helium pycnometry method. In short, the new DHE-GC method is simple, rapid, and accurate, making it a valuable tool for shale gas-related research and applications.

  15. Quantitative analysis of total starch content in wheat flour by reaction headspace gas chromatography.

    Science.gov (United States)

    Xie, Wei-Qi; Gong, Yi-Xian; Yu, Kong-Xian

    2017-09-01

    This paper proposed a new reaction headspace gas chromatographic (HS-GC) method for efficiently quantifying the total starch content in wheat flours. A certain weight of wheat flour was oxidized by potassium dichromate in an acidic condition in a sealed headspace vial. The results show that the starch in wheat flour can be completely transferred to carbon dioxide at the given conditions (at 100 °C for 40 min) and the total starch content in wheat flour sample can be indirectly quantified by detecting the CO 2 formed from the oxidation reaction. The data showed that the relative standard deviation of the reaction HS-GC method in the precision test was less than 3.06%, and the relative differences between the new method and the reference method (titration method) were no more than 8.90%. The new reaction HS-GC method is automated, accurate, and can be a reliable tool for determining the total starch content in wheat flours in both laboratory and industrial applications. Graphical abstract The total starch content in wheat flour can be indirectly quantified by the GC detection of the CO 2 formed from the oxidation reaction between wheat flour and potassium dichromate in an acidic condition.

  16. Quantification of Polyfunctional Thiols in Wine by HS-SPME-GC-MS Following Extractive Alkylation.

    Science.gov (United States)

    Musumeci, Lauren E; Ryona, Imelda; Pan, Bruce S; Loscos, Natalia; Feng, Hui; Cleary, Michael T; Sacks, Gavin L

    2015-07-06

    Analyses of key odorous polyfunctional volatile thiols in wines (3-mercaptohexanol (3-MH), 3-mercaptohexylacetate (3-MHA), and 4-mercapto-4-methyl-2-pentanone (4-MMP)) are challenging due to their high reactivity and ultra-trace concentrations, especially when using conventional gas-chromatography electron impact mass spectrometry (GC-EI-MS). We describe a method in which thiols are converted to pentafluorobenzyl (PFB) derivatives by extractive alkylation and the organic layer is evaporated prior to headspace solid phase microextraction (HS-SPME) and GC-EI-MS analysis. Optimal parameters were determined by response surface area modeling. The addition of NaCl solution to the dried SPME vials prior to extraction resulted in up to less than fivefold improvement in detection limits. Using 40 mL wine samples, limits of detection for 4-MMP, 3-MH, and 3-MHA were 0.9 ng/L, 1 ng/L, and 17 ng/L, respectively. Good recovery (90%-109%) and precision (5%-11% RSD) were achieved in wine matrices. The new method was used to survey polyfunctional thiol concentrations in 61 commercial California and New York State wines produced from V. vinifera (Riesling, Gewürztraminer, Cabernet Sauvignon, Sauvignon blanc and non-varietal rosé wines), V. labruscana (Niagara), and Vitis spp. (Cayuga White). Mean 4-MMP concentrations in New York Niagara (17 ng/L) were not significantly different from concentrations in Sauvignon blanc, but were significantly higher than 4-MMP in other varietal wines.

  17. Determination of Lactones in Wines by Headspace Solid-Phase Microextraction and Gas Chromatography Coupled with Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    S. J. Pérez-Olivero

    2014-01-01

    Full Text Available Application of headspace solid-phase microextraction (HS-SPME coupled with high-resolution gas chromatographic (HRGC analysis was studied for determining lactones in wines. Six different SPME fibers were tested, and the influence of different factors such as temperature and time of desorption, ionic strength, time of extraction, content of sugar, ethanol, tannins and anthocyanins, and pH and influence of SO2 were studied. The proposed HS-SPME-GC method is an appropriate technique for the quantitative analysis of γ-butyrolactone, γ-hexalactone, trans-whiskey lactone, γ-octalactone, cis-whiskey lactone, γ-nonalactone, γ-decalactone, δ-decalactone, and γ-undecalactone in wines. Method reproducibility and repeatability ranged between 0.6 and 5.2% for all compounds. Detection limit for γ-butyrolactone was 0.17 mg/L and a few μg/L for the rest of the compounds. The optimized method has been applied to several wine samples.

  18. Comparison of direct, headspace and headspace cold fiber modes in solid phase microextraction of polycyclic aromatic hydrocarbons by a new coating based on poly(3,4-ethylenedioxythiophene)/graphene oxide composite.

    Science.gov (United States)

    Banitaba, Mohammad Hossein; Hosseiny Davarani, Saied Saeed; Kazemi Movahed, Siyavash

    2014-01-17

    A novel nanocomposite coating made of poly(3,4-ethylenedioxythiophene) (PEDOT) and graphene oxide was electrochemically prepared on gold wire. The prepared fiber was applied to the solid-phase microextraction (SPME) and gas chromatographic analysis of six polycyclic aromatic hydrocarbons (PAHs). Three modes of extraction i.e. direct immersion (DI), headspace (HS) and headspace cold fiber (HS-CF) in SPME were investigated. The results were compared under optimized conditions of each mode, considering the effects of the three most important parameters which are extraction temperature, extraction time and ionic strength. The comparison showed that HS-CF-SPME results in the best outcome for the extraction of PAHs from water samples. Under the optimized conditions of this mode, the calibration curves were linear within the range of 0.4-600μgL(-1) and the detection limits were between 0.05 and 0.13μgL(-1). The intra-day and inter-day relative standard deviations obtained at 10μgL(-1) (n=5), using a single fiber, were 4.1-6.8% and 4.8-8.4%, respectively. The fiber-to-fiber repeatabilities (n=4), expressed as the relative standard deviations (RSD%), were between 6.5% and 10.7% at a 10μgL(-1) concentration level. The method was successfully applied to the analysis of PAHs in seawater samples showing recoveries from 85% to 107%. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. High-throughput analysis using non-depletive SPME: challenges and applications to the determination of free and total concentrations in small sample volumes.

    Science.gov (United States)

    Boyacı, Ezel; Bojko, Barbara; Reyes-Garcés, Nathaly; Poole, Justen J; Gómez-Ríos, Germán Augusto; Teixeira, Alexandre; Nicol, Beate; Pawliszyn, Janusz

    2018-01-18

    In vitro high-throughput non-depletive quantitation of chemicals in biofluids is of growing interest in many areas. Some of the challenges facing researchers include the limited volume of biofluids, rapid and high-throughput sampling requirements, and the lack of reliable methods. Coupled to the above, growing interest in the monitoring of kinetics and dynamics of miniaturized biosystems has spurred the demand for development of novel and revolutionary methodologies for analysis of biofluids. The applicability of solid-phase microextraction (SPME) is investigated as a potential technology to fulfill the aforementioned requirements. As analytes with sufficient diversity in their physicochemical features, nicotine, N,N-Diethyl-meta-toluamide, and diclofenac were selected as test compounds for the study. The objective was to develop methodologies that would allow repeated non-depletive sampling from 96-well plates, using 100 µL of sample. Initially, thin film-SPME was investigated. Results revealed substantial depletion and consequent disruption in the system. Therefore, new ultra-thin coated fibers were developed. The applicability of this device to the described sampling scenario was tested by determining the protein binding of the analytes. Results showed good agreement with rapid equilibrium dialysis. The presented method allows high-throughput analysis using small volumes, enabling fast reliable free and total concentration determinations without disruption of system equilibrium.

  20. Ethanol analysis by headspace gas chromatography with simultaneous flame-ionization and mass spectrometry detection.

    Science.gov (United States)

    Tiscione, Nicholas B; Alford, Ilene; Yeatman, Dustin Tate; Shan, Xiaoqin

    2011-09-01

    Ethanol is the most frequently identified compound in forensic toxicology. Although confirmation involving mass spectrometry is desirable, relatively few methods have been published to date. A novel technique utilizing a Dean's Switch to simultaneously quantitate and confirm ethyl alcohol by flame-ionization (FID) and mass spectrometric (MS) detection after headspace sampling and gas chromatographic separation is presented. Using 100 μL of sample, the limits of detection and quantitation were 0.005 and 0.010 g/dL, respectively. The zero-order linear range (r(2) > 0.990) was determined to span the concentrations of 0.010 to 1.000 g/dL. The coefficient of variation of replicate analyses was less than 3.1%. Quantitative accuracy was within ±8%, ±6%, ±3%, and ±1.5% at concentrations of 0.010, 0.025, 0.080, and 0.300 g/dL, respectively. In addition, 1,1-difluoroethane was validated for qualitative identification by this method. The validated FID-MS method provides a procedure for the quantitation of ethyl alcohol in blood by FID with simultaneous confirmation by MS and can also be utilized as an identification method for inhalants such as 1,1-difluoroethane.

  1. HS-SPME-GC-MS analysis of antioxidant degradation products migrating to drinking water from PE materials and PEX pipes

    DEFF Research Database (Denmark)

    Lützhøft, Hans-Christian Holten; Waul, Christopher Kevin; Andersen, Henrik Rasmus

    2013-01-01

    degradation products may leach and enter drinking water. The aim of this investigation was to develop a method for measuring these degradation products with a performance meeting the drinking water quality criteria of 20 µg L−1. Using headspace solid phase microextraction coupled to a gas chromatograph......Polyethylene (PE) and cross-linked polyethylene (PEX) pipes are frequently used in water supply systems. Such pipes contain added antioxidants with phenolic structures, e.g. Irgafos 168, Irganox 1010 and 1076, in order to improve durability. However, phenol, ketone and quinone antioxidant...

  2. Multiple headspace-solid-phase microextraction: an application to quantification of mushroom volatiles.

    Science.gov (United States)

    Costa, Rosaria; Tedone, Laura; De Grazia, Selenia; Dugo, Paola; Mondello, Luigi

    2013-04-03

    Multiple headspace-solid phase microextraction (MHS-SPME) followed by gas chromatography/mass spectrometry (GC-MS) and flame ionization detection (GC-FID) was applied to the identification and quantification of volatiles released by the mushroom Agaricus bisporus, also known as champignon. MHS-SPME allows to perform quantitative analysis of volatiles from solid matrices, free of matrix interferences. Samples analyzed were fresh mushrooms (chopped and homogenized) and mushroom-containing food dressings. 1-Octen-3-ol, 3-octanol, 3-octanone, 1-octen-3-one and benzaldehyde were common constituents of the samples analyzed. Method performance has been tested through the evaluation of limit of detection (LoD, range 0.033-0.078 ng), limit of quantification (LoQ, range 0.111-0.259 ng) and analyte recovery (92.3-108.5%). The results obtained showed quantitative differences among the samples, which can be attributed to critical factors, such as the degree of cell damage upon sample preparation, that are here discussed. Considerations on the mushrooms biochemistry and on the basic principles of MHS analysis are also presented. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Quantitative analysis of aldehydes in canned vegetables using static headspace-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Serrano, María; Gallego, Mercedes; Silva, Manuel

    2017-11-17

    Volatile aldehydes appear in canned vegetables as constituents and some of them can also be present as disinfection by-products (DBPs) because of the contact between vegetables and treated water. This paper describes two static headspace-gas chromatography-mass spectrometry (SHS-GC-MS) methods to determine 15 aldehydes in both the solid and the liquid phases of canned vegetables. The treatment for both phases of samples was carried out simultaneously into an SHS unit, including the leaching of the aldehydes (from the vegetable), their derivatization and volatilization of the oximes formed. Detection limits were obtained within the range of 15-400μg/kg and 3-40μg/L for aldehydes in the solid and the liquid phases of the food, respectively. The relative standard deviation was lower than 7% -for the whole array of the target analytes-, the trueness evaluated by recovery experiments provided %recoveries between 89 and 99% and short- and long-term stability studies indicated there was no significant variation in relative peak areas of all aldehydes in both phases of canned vegetables after their storing at 4°C for two weeks. The study of the origin of the 15 aldehydes detected between both phases of canned vegetables showed that: i) the presence of 13 aldehydes -at average concentrations of 2.2-39μg/kg and 0.25-71μg/L for the solid and the liquid phases, respectively- is because they are natural constituents of vegetables; and ii) the presence of glyoxal and methylglyoxal -which are mainly found in the liquid phase (average values, 1.4-4.1μg/L)- is ascribed to the use of treated water, thereby being DBPs. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Optimization of the HS-SPME-GC/MS technique for the analysis of volatile compounds in caprine Coalho cheese using response surface methodology

    Directory of Open Access Journals (Sweden)

    Taliana Kênia Alves BEZERRA

    2016-03-01

    Full Text Available Abstract Caprine Coalho cheese presents great potential for a typical protected designation of origin, considering that this traditional Brazilian cheese presents a slightly salty and acid flavor, combined with a unique texture. This study optimized the HS-SPME-GC-MS methodology for volatile analysis of Coalho cheese, which can be used as a tool to help in the identification of the distinctive aroma profile of this cheese. The conditions of equilibrium time, extraction temperature and time were optimized using the statistical tool factorial experimental design 23, and applying the desirability function. After the evaluation, it was concluded that the optimum extraction conditions comprised equilibrium and extraction time of 20 and 40 minutes, respectively; and ideal extraction temperature of 45 °C. The optimum extraction of volatile compounds in goat Coalho cheese captured 32 volatile compounds: 5 alcohols, 5 esters, 3 ketones, 6 acids, 3 aldehydes, 3 terpenes, and 7 hydrocarbons.

  5. Optimization of biological and instrumental detection of explosives and ignitable liquid residues including canines, SPME/ITMS and GC/MSn

    Science.gov (United States)

    Furton, Kenneth G.; Harper, Ross J.; Perr, Jeannette M.; Almirall, Jose R.

    2003-09-01

    A comprehensive study and comparison is underway using biological detectors and instrumental methods for the rapid detection of ignitable liquid residues (ILR) and high explosives. Headspace solid phase microextraction (SPME) has been demonstrated to be an effective sampling method helping to identify active odor signature chemicals used by detector dogs to locate forensic specimens as well as a rapid pre-concentration technique prior to instrumental detection. Common ignitable liquids and common military and industrial explosives have been studied including trinitrotoluene, tetryl, RDX, HMX, EGDN, PETN and nitroglycerine. This study focuses on identifying volatile odor signature chemicals present, which can be used to enhance the level and reliability of detection of ILR and explosives by canines and instrumental methods. While most instrumental methods currently in use focus on particles and on parent organic compounds, which are often involatile, characteristic volatile organics are generally also present and can be exploited to enhance detection particularly for well-concealed devices. Specific examples include the volatile odor chemicals 2-ethyl-1-hexanol and cyclohexanone, which are readily available in the headspace of the high explosive composition C-4; whereas, the active chemical cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX) is not. The analysis and identification of these headspace 'fingerprint' organics is followed by double-blind dog trials of the individual components using certified teams in an attempt to isolate and understand the target compounds to which dogs are sensitive. Studies to compare commonly used training aids with the actual target explosive have also been undertaken to determine their suitability and effectiveness. The optimization of solid phase microextraction (SPME) combined with ion trap mobility spectrometry (ITMS) and gas chromatography/mass spectrometry/mass spectrometry (GC/MSn) is detailed including interface development

  6. Microextração por fase sólida SPME, Solid Phase Micro-Extration

    Directory of Open Access Journals (Sweden)

    Antonio Luiz Pires Valente

    2000-08-01

    Full Text Available Fundamental aspects of Solid Phase Micro-Extraction (SPME are discussed in the present paper. The application of SPME as a microtechnique of sample preparation for gas chromatographic analysis is considered and related to existing theoretical models. Both research prototypes and commercial SPME devices are considered.

  7. Optimization of headspace solid-phase microextraction for analysis of {beta}-caryophyllene in a nanoemulsion dosage form prepared with copaiba (Copaifera multijuga Hayne) oil

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Daiane de O; Colombo, Mariana; Kelmann, Regina G. [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Av. Ipiranga, 2752, CEP 90610-000 (Brazil); De Souza, Tatiane P. [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Universidade Federal do Amazonas, Manaus, Amazonas (Brazil); Bassani, Valquiria L.; Teixeira, Helder F. [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Av. Ipiranga, 2752, CEP 90610-000 (Brazil); Veiga, Valdir F. [Departamento de Quimica, Instituto de Ciencias Exatas, UFAM, Av. Gal. Rodrigo Octavio, 6.200 - Japiim, 69.079-000, Manaus - AM (Brazil); Limberger, Renata P. [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Av. Ipiranga, 2752, CEP 90610-000 (Brazil); and others

    2012-04-06

    Highlights: Black-Right-Pointing-Pointer A SPME-CG method is proposed for {beta}-caryophyllene assay in nanoemulsions containing copaiba oil. Black-Right-Pointing-Pointer SPME parameters were optimized for efficient {beta}-caryophyllene extraction. Black-Right-Pointing-Pointer The stability-indicating capability and specificity of the method were satisfied. Black-Right-Pointing-Pointer Nanoemulsions partially protected {beta}-caryophyllene under stressing conditions. Black-Right-Pointing-Pointer The proposed method presents linearity, lows LOD and LOQ, good precision, accuracy and robustness. - Abstract: Recent studies have shown the anti-inflammatory activity of Copaiba oils may be addressed to the high content of {beta}-caryophyllene, the most common sesquiterpene detected, especially in the Copaifera multijuga Hayne species. In the present study, nanoemulsions were proposed as a delivery system for copaiba oil in view to treat locally inflamed skin. This article describes the optimization and validation of a stability-indicating SPME-GC method, for {beta}-caryophyllene analysis in the nanoemulsions produced by high pressure homogenization. SPME methods are performed with PDMS (polydimethylsiloxane) fiber (100 {mu}m). Three SPME parameters were evaluated by a three-level-three-factor Box-Behnken factorial design as potentially affecting the technique efficiency. According to the results obtained, the best conditions to extract {beta}-caryophyllene were: (i) sampling temperature of 45 Degree-Sign C, (ii) sampling time of 20 min and (iii) no NaCl addition. Results coming from the forced degradation tests showed a reduction of {beta}-caryophyllene peak area when both caryophyllene methanolic solution and nanoemulsions were exposed to acid hydrolysis, UV-A irradiation, oxidative (H{sub 2}O{sub 2}) and thermolitic (60 Degree-Sign C) conditions. Such reduction occurred in lower extent in the nanoemulsions, suggesting a protective effect of the formulation to {beta

  8. Optimization of headspace solid-phase microextraction for analysis of β-caryophyllene in a nanoemulsion dosage form prepared with copaiba (Copaifera multijuga Hayne) oil

    International Nuclear Information System (INIS)

    Dias, Daiane de O; Colombo, Mariana; Kelmann, Regina G.; De Souza, Tatiane P.; Bassani, Valquiria L.; Teixeira, Helder F.; Veiga, Valdir F.; Limberger, Renata P.

    2012-01-01

    Highlights: ► A SPME-CG method is proposed for β-caryophyllene assay in nanoemulsions containing copaiba oil. ► SPME parameters were optimized for efficient β-caryophyllene extraction. ► The stability-indicating capability and specificity of the method were satisfied. ► Nanoemulsions partially protected β-caryophyllene under stressing conditions. ► The proposed method presents linearity, lows LOD and LOQ, good precision, accuracy and robustness. - Abstract: Recent studies have shown the anti-inflammatory activity of Copaiba oils may be addressed to the high content of β-caryophyllene, the most common sesquiterpene detected, especially in the Copaifera multijuga Hayne species. In the present study, nanoemulsions were proposed as a delivery system for copaiba oil in view to treat locally inflamed skin. This article describes the optimization and validation of a stability-indicating SPME-GC method, for β-caryophyllene analysis in the nanoemulsions produced by high pressure homogenization. SPME methods are performed with PDMS (polydimethylsiloxane) fiber (100 μm). Three SPME parameters were evaluated by a three-level-three-factor Box–Behnken factorial design as potentially affecting the technique efficiency. According to the results obtained, the best conditions to extract β-caryophyllene were: (i) sampling temperature of 45 °C, (ii) sampling time of 20 min and (iii) no NaCl addition. Results coming from the forced degradation tests showed a reduction of β-caryophyllene peak area when both caryophyllene methanolic solution and nanoemulsions were exposed to acid hydrolysis, UV-A irradiation, oxidative (H 2 O 2 ) and thermolitic (60 °C) conditions. Such reduction occurred in lower extent in the nanoemulsions, suggesting a protective effect of the formulation to β-caryophyllene content. Since no degradation products were detected in the same retention time of β-caryophyllene, the specificity of the method was demonstrated. The method was linear in

  9. Determination of Sesquiterpenes in Wines by HS-SPME Coupled with GC-MS

    OpenAIRE

    Cincotta, Fabrizio; Verzera, Antonella; Tripodi, Gianluca; Condurso, Concetta

    2015-01-01

    The sesquiterpene compounds present in red wines were characterized and quantified by Headspace Solid-Phase Microextraction in combination with Gas Chromatography–Mass Spectrometry (HS-SPME-GC-MS). Sixteen sesquiterpenes were identified, mainly hydrocarbons but also derived oxygenated compounds. Sesquiterpenes were acyclic, monocyclic, byciclic and tryciclic. Sesquiterpenes were detected in SIM (selected ion monitoring) mode using their characteristics ions. All the sesquiterpenes were identi...

  10. Multi-volatile method for aroma analysis using sequential dynamic headspace sampling with an application to brewed coffee.

    Science.gov (United States)

    Ochiai, Nobuo; Tsunokawa, Jun; Sasamoto, Kikuo; Hoffmann, Andreas

    2014-12-05

    A novel multi-volatile method (MVM) using sequential dynamic headspace (DHS) sampling for analysis of aroma compounds in aqueous sample was developed. The MVM consists of three different DHS method parameters sets including choice of the replaceable adsorbent trap. The first DHS sampling at 25 °C using a carbon-based adsorbent trap targets very volatile solutes with high vapor pressure (>20 kPa). The second DHS sampling at 25 °C using the same type of carbon-based adsorbent trap targets volatile solutes with moderate vapor pressure (1-20 kPa). The third DHS sampling using a Tenax TA trap at 80 °C targets solutes with low vapor pressure (0.9910) and high sensitivity (limit of detection: 1.0-7.5 ng mL(-1)) even with MS scan mode. The feasibility and benefit of the method was demonstrated with analysis of a wide variety of aroma compounds in brewed coffee. Ten potent aroma compounds from top-note to base-note (acetaldehyde, 2,3-butanedione, 4-ethyl guaiacol, furaneol, guaiacol, 3-methyl butanal, 2,3-pentanedione, 2,3,5-trimethyl pyrazine, vanillin, and 4-vinyl guaiacol) could be identified together with an additional 72 aroma compounds. Thirty compounds including 9 potent aroma compounds were quantified in the range of 74-4300 ng mL(-1) (RSD<10%, n=5). Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Multivariate analysis of the volatile components in tobacco based on infrared-assisted extraction coupled to headspace solid-phase microextraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Yang, Yanqin; Pan, Yuanjiang; Zhou, Guojun; Chu, Guohai; Jiang, Jian; Yuan, Kailong; Xia, Qian; Cheng, Changhe

    2016-11-01

    A novel infrared-assisted extraction coupled to headspace solid-phase microextraction followed by gas chromatography with mass spectrometry method has been developed for the rapid determination of the volatile components in tobacco. The optimal extraction conditions for maximizing the extraction efficiency were as follows: 65 μm polydimethylsiloxane-divinylbenzene fiber, extraction time of 20 min, infrared power of 175 W, and distance between the infrared lamp and the headspace vial of 2 cm. Under the optimum conditions, 50 components were found to exist in all ten tobacco samples from different geographical origins. Compared with conventional water-bath heating and nonheating extraction methods, the extraction efficiency of infrared-assisted extraction was greatly improved. Furthermore, multivariate analysis including principal component analysis, hierarchical cluster analysis, and similarity analysis were performed to evaluate the chemical information of these samples and divided them into three classifications, including rich, moderate, and fresh flavors. The above-mentioned classification results were consistent with the sensory evaluation, which was pivotal and meaningful for tobacco discrimination. As a simple, fast, cost-effective, and highly efficient method, the infrared-assisted extraction coupled to headspace solid-phase microextraction technique is powerful and promising for distinguishing the geographical origins of the tobacco samples coupled to suitable chemometrics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Modified HS-SPME for determination of quantitative relations between low-molecular oxygen compounds in various matrices.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Szewczyk, Joanna; Dybowski, Michal P

    2016-09-07

    Similar quantitative relations between individual constituents of the liquid sample established by its direct injection can be obtained applying Polydimethylsiloxane (PDMS) fiber in the headspace solid phase microextraction (HS-SPME) system containing the examined sample suspended in methyl silica oil. This paper proves that the analogous system composed of sample suspension/emulsion in polyethylene glycol (PEG) and Carbowax fiber allows to get similar quantitative relations between components of the mixture as those established by its direct analysis, but only for polar constituents. It is demonstrated for essential oil (EO) components of savory, sage, mint and thyme, and of artificial liquid mixture of polar constituents. The observed differences in quantitative relations between polar constituents estimated by both applied procedures are insignificant (Fexp < Fcrit). The presented results indicates that wider applicability of the system composed of a sample suspended in the oil of the same physicochemical character as that of used SPME fiber coating strongly depends on the character of interactions between analytes-suspending liquid and analytes-fiber coating. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Rapid analysis of dissolved methane, ethylene, acetylene and ethane using partition coefficients and headspace-gas chromatography.

    Science.gov (United States)

    Lomond, Jasmine S; Tong, Anthony Z

    2011-01-01

    Analysis of dissolved methane, ethylene, acetylene, and ethane in water is crucial in evaluating anaerobic activity and investigating the sources of hydrocarbon contamination in aquatic environments. A rapid chromatographic method based on phase equilibrium between water and its headspace is developed for these analytes. The new method requires minimal sample preparation and no special apparatus except those associated with gas chromatography. Instead of Henry's Law used in similar previous studies, partition coefficients are used for the first time to calculate concentrations of dissolved hydrocarbon gases, which considerably simplifies the calculation involved. Partition coefficients are determined to be 128, 27.9, 1.28, and 96.3 at 30°C for methane, ethylene, acetylene, and ethane, respectively. It was discovered that the volume ratio of gas-to-liquid phase is critical to the accuracy of the measurements. The method performance can be readily improved by reducing the volume ratio of the two phases. Method validation shows less than 6% variation in accuracy and precision except at low levels of methane where interferences occur in ambient air. Method detection limits are determined to be in the low ng/L range for all analytes. The performance of the method is further tested using environmental samples collected from various sites in Nova Scotia.

  14. Headspace Hanging Drop Liquid Phase Microextraction and Gas Chromatography-Mass Spectrometry for the Analysis of Flavors from Clove Buds

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Mi Jin; Shin, Yeon Jae; Oh, Se Yeon; Kim, Nam Sun; Kim, Kun; Lee, Dong Sun [Seoul Women' s University, Seoul (Korea, Republic of)

    2006-02-15

    A novel sample pretreatment technique, headspace hanging drop liquid phase microextraction (HS-LPME) was studied and applied to the determination of flavors from solid clove buds by gas chromatography-mass spectrometry (GC-MS). Several parameters affecting on HS-LPME such as organic solvent drop volume, extraction time, extraction temperature and phase ratio were investigated. 1-Octanol was selected as the extracting solvent, drop size was fixed to 0.6 μL. 60 min extraction time at 25 .deg. C was chosen. HS-LPME has the good efficiency demonstrated by the higher partition equilibrium constant (K{sub lh}) values and concentration factor (CF) values. The limits of detection (LOD) were 1.5-3.2 ng. The amounts of eugenol, β-caryophyllene and eugenol acetate from the clove bud sample were 1.90 mg/g, 1.47 mg/g and 7.0 mg/g, respectively. This hanging drop based method is a simple, fast and easy sample enrichment technique using minimal solvent. HSLPME is an alternative sample preparation method for the analysis of volatile aroma compounds by GC-MS.

  15. Direct analysis of volatile organic compounds in foods by headspace extraction atmospheric pressure chemical ionisation mass spectrometry.

    Science.gov (United States)

    Perez-Hurtado, P; Palmer, E; Owen, T; Aldcroft, C; Allen, M H; Jones, J; Creaser, C S; Lindley, M R; Turner, M A; Reynolds, J C

    2017-11-30

    The rapid screening of volatile organic compounds (VOCs) by direct analysis has potential applications in the areas of food and flavour science. Currently, the technique of choice for VOC analysis is gas chromatography/mass spectrometry (GC/MS). However, the long chromatographic run times and elaborate sample preparation associated with this technique have led a movement towards direct analysis techniques, such as selected ion flow tube mass spectrometry (SIFT-MS), proton transfer reaction mass spectrometry (PTR-MS) and electronic noses. The work presented here describes the design and construction of a Venturi jet-pump-based modification for a compact mass spectrometer which enables the direct introduction of volatiles for qualitative and quantitative analysis. Volatile organic compounds were extracted from the headspace of heated vials into the atmospheric pressure chemical ionization source of a quadrupole mass spectrometer using a Venturi pump. Samples were analysed directly with no prior sample preparation. Principal component analysis (PCA) was used to differentiate between different classes of samples. The interface is shown to be able to routinely detect problem analytes such as fatty acids and biogenic amines without the requirement of a derivatisation step, and is shown to be able to discriminate between four different varieties of cheese with good intra and inter-day reproducibility using an unsupervised PCA model. Quantitative analysis is demonstrated using indole standards with limits of detection and quantification of 0.395 μg/mL and 1.316 μg/mL, respectively. The described methodology can routinely detect highly reactive analytes such as volatile fatty acids and diamines without the need for a derivatisation step or lengthy chromatographic separations. The capability of the system was demonstrated by discriminating between different varieties of cheese and monitoring the spoilage of meats. © 2017 The Authors. Rapid Communications in Mass

  16. Analysis of volatile compounds in gluten-free bread crusts with an optimised and validated SPME-GC/QTOF methodology.

    Science.gov (United States)

    Pico, Joana; Antolín, Beatriz; Román, Laura; Gómez, Manuel; Bernal, José

    2018-04-01

    The aroma of bread crust, as one of the first characteristics perceived, is essential for bread acceptance. However, gluten-free bread crusts exhibit weak aroma. A SPME-GC/QTOF methodology was optimised with PCA and RSM and validated for the quantification of 44 volatile compounds in bread crust, extracting 0.75 g of crust at 60 °C for 51 min. LODs ranged between 3.60 and 1760 μg Kg -1 , all the R 2 were higher than 0.99 and %RSD for precision and %Er for accuracy were lower than 9% and 12%, respectively. A commercial wheat bread crust was quantified, and furfural was the most abundant compound. Bread crusts of wheat starch and of japonica rice, basmati rice and teff flours were also quantified. Teff flour and wheat starch crusts were very suitable for improving gluten-free bread crust aroma, due to their similar content in 2-acetyl-1-pyrroline and 4-hydroxy-2,5-dimethyl-3(2H)-furanone compared to wheat flour crust and also for their high content in pyrazines. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Development and Validation of a SPME-GC-MS Method for In situ Passive Sampling of Root Volatiles from Glasshouse-Grown Broccoli Plants Undergoing Below-Ground Herbivory by Larvae of Cabbage Root Fly, Delia radicum L.

    Science.gov (United States)

    Deasy, William; Shepherd, Tom; Alexander, Colin J; Birch, A Nicholas E; Evans, K Andrew

    2016-11-01

    Research on plant root chemical ecology has benefited greatly from recent developments in analytical chemistry. Numerous reports document techniques for sampling root volatiles, although only a limited number describe in situ collection. To demonstrate a new method for non-invasive in situ passive sampling using solid phase micro extraction (SPME), from the immediate vicinity of growing roots. SPME fibres inserted into polyfluorotetrafluoroethylene (PTFE) sampling tubes located in situ which were either perforated, covered with stainless steel mesh or with microporous PTFE tubing, were used for non-invasive sub-surface sampling of root volatiles from glasshouse-grown broccoli. Sampling methods were compared with above surface headspace collection using Tenax TA. The roots were either mechanically damaged or infested with Delia radicum larvae. Principal component analysis (PCA) was used to investigate the effect of damage on the composition of volatiles released by broccoli roots. Analyses by gas chromatography-mass spectrometry (GC-MS) with SPME and automated thermal desorption (ATD) confirmed that sulphur compounds, showing characteristic temporal emission patterns, were the principal volatiles released by roots following insect larval damage. Use of SPME with in situ perforated PTFE sampling tubes was the most robust method for out-of-lab sampling. This study describes a new method for non-invasive passive sampling of volatiles in situ from intact and insect damaged roots using SPME. The method is highly suitable for remote sampling and has potential for wide application in chemical ecology/root/soil research. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  18. Zero-Headspace Coal-Core Gas Desorption Canister, Revised Desorption Data Analysis Spreadsheets and a Dry Canister Heating System

    Science.gov (United States)

    Barker, Charles E.; Dallegge, Todd A.

    2005-01-01

    Coal desorption techniques typically use the U.S. Bureau of Mines (USBM) canister-desorption method as described by Diamond and Levine (1981), Close and Erwin (1989), Ryan and Dawson (1993), McLennan and others (1994), Mavor and Nelson (1997) and Diamond and Schatzel (1998). However, the coal desorption canister designs historically used with this method have an inherent flaw that allows a significant gas-filled headspace bubble to remain in the canister that later has to be compensated for by correcting the measured desorbed gas volume with a mathematical headspace volume correction (McLennan and others, 1994; Mavor and Nelson, 1997).

  19. Graphene deposited onto aligned zinc oxide nanorods as an efficient coating for headspace solid-phase microextraction of gasoline fractions from oil samples.

    Science.gov (United States)

    Wen, Congying; Li, Mengmeng; Li, Wangbo; Li, Zizhou; Duan, Wei; Li, Yulong; Zhou, Jie; Li, Xiyou; Zeng, Jingbin

    2017-12-29

    The content of gasoline fraction in oil samples is not only an important indicator of oil quality, but also an indispensable fundamental data for oil refining and processing. Before its determination, efficient preconcentration and separation of gasoline fractions from complicated matrices is essential. In this work, a thin layer of graphene (G) was deposited onto oriented ZnO nanorods (ZNRs) as a SPME coating. By this approach, the surface area of G was greatly enhanced by the aligned ZNRs, and the surface polarity of ZNRs was changed from polar to less polar, which were both beneficial for the extraction of gasoline fractions. In addition, the ZNRs were well protected by the mechanically and chemically stable G, making the coating highly durable for use. With headspace SPME (HS-SPME) mode, the G/ZNRs coating can effectively extract gasoline fractions from various oil samples, whose extraction efficiency achieved 1.5-5.4 and 2.1-8.2 times higher than those of a G and commercial 7-μm PDMS coating respectively. Coupled with GC-FID, the developed method is sensitive, simple, cost effective and easily accessible for the analysis of gasoline fractions. Moreover, the method is also feasible for the detection of gasoline markers in simulated oil-polluted water, which provides an option for the monitoring of oil spill accident. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Determination of furfural and hydroxymethylfurfural from baby formula using headspace solid phase microextraction based on nanostructured polypyrrole fiber coupled with ion mobility spectrometry.

    Science.gov (United States)

    Kamalabadi, Mahdie; Ghaemi, Elham; Mohammadi, Abdorreza; Alizadeh, Naader

    2015-08-15

    Furfural (Fu) and hydroxymethylfurfural (HMFu) are extracted using a dodecylbenzenesulfonate-doped polypyrrole coating as a fiber for headspace solid phase microextraction (HS-SPME) method in baby formula samples and detected using ion mobility spectrometry (IMS). Sample pH, salt effect, extraction time and temperature were investigated and optimized as effective parameters in HS-SPME. The calibration curves were linear in the range of 20-300 ng g(-1) (R(2)>0.99). Limits of detection for Fu and HMFu were 6 ng g(-1) and 5 ng g(-1), respectively. The RSD% of Fu and HMFu for five analyses was 4.4 and 4.9, respectively. The proposed method was successfully applied to determine of Fu and HMFu in the different baby formula samples with satisfactory result. The results were in agreement with those obtained using HPLC analysis. The HS-SPME-IMS is precise, selective and sensitive analytical method for determination of Fu and HMFu in baby formula samples, without any derivatization process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Simple and accurate quantification of BTEX in ambient air by SPME and GC-MS.

    Science.gov (United States)

    Baimatova, Nassiba; Kenessov, Bulat; Koziel, Jacek A; Carlsen, Lars; Bektassov, Marat; Demyanenko, Olga P

    2016-07-01

    Benzene, toluene, ethylbenzene and xylenes (BTEX) comprise one of the most ubiquitous and hazardous groups of ambient air pollutants of concern. Application of standard analytical methods for quantification of BTEX is limited by the complexity of sampling and sample preparation equipment, and budget requirements. Methods based on SPME represent simpler alternative, but still require complex calibration procedures. The objective of this research was to develop a simpler, low-budget, and accurate method for quantification of BTEX in ambient air based on SPME and GC-MS. Standard 20-mL headspace vials were used for field air sampling and calibration. To avoid challenges with obtaining and working with 'zero' air, slope factors of external standard calibration were determined using standard addition and inherently polluted lab air. For polydimethylsiloxane (PDMS) fiber, differences between the slope factors of calibration plots obtained using lab and outdoor air were below 14%. PDMS fiber provided higher precision during calibration while the use of Carboxen/PDMS fiber resulted in lower detection limits for benzene and toluene. To provide sufficient accuracy, the use of 20mL vials requires triplicate sampling and analysis. The method was successfully applied for analysis of 108 ambient air samples from Almaty, Kazakhstan. Average concentrations of benzene, toluene, ethylbenzene and o-xylene were 53, 57, 11 and 14µgm(-3), respectively. The developed method can be modified for further quantification of a wider range of volatile organic compounds in air. In addition, the new method is amenable to automation. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Automated determination of aliphatic primary amines in wastewater by simultaneous derivatization and headspace solid-phase microextraction followed by gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Llop, Anna; Pocurull, Eva; Borrull, Francesc

    2010-01-22

    This paper presents a fully automated method for determining ten primary amines in wastewater at ng/L levels. The method is based on simultaneous derivatization with pentafluorobenzaldehyde (PFBAY) and headspace solid-phase microextraction (HS-SPME) followed by gas chromatography coupled to ion trap tandem mass spectrometry (GC-IT-MS-MS). The influence of main factors on the efficiency of derivatization and of HS-SPME is described in detail and optimized by a central composite design. For all species, the highest enrichment factors were achieved using a 85 microm polyacrylate (PA) fiber exposed in the headspace of stirred water samples (750 rpm) at pH 12, containing 360 g/L of NaCl, at 40 degrees C for 15 min. Under optimized conditions, the proposed method achieved detection limits ranging from 10 to 100 ng/L (except for cyclohexylamine). The optimized method was then used to determine the presence of primary amines in various types of wastewater samples, such as influent and effluent wastewater from municipal and industrial wastewater treatment plants (WWTPs) and a potable water treatment plant. Although the analysis of these samples revealed the presence of up to 1500 microg/L of certain primary amines in influent industrial wastewater, the concentration of these compounds in the effluent and in municipal and potable water was substantially lower, at low microg/L levels. The new derivatization-HS-SPME-GC-IT-MS-MS method is suitable for the fast, reliable and inexpensive determination of primary amines in wastewater in an automated procedure. Copyright 2009 Elsevier B.V. All rights reserved.

  3. Headspace needle-trap analysis of priority volatile organic compounds from aqueous samples: application to the analysis of natural and waste waters.

    Science.gov (United States)

    Alonso, Monica; Cerdan, Laura; Godayol, Anna; Anticó, Enriqueta; Sanchez, Juan M

    2011-11-11

    Combining headspace (HS) sampling with a needle-trap device (NTD) to determine priority volatile organic compounds (VOCs) in water samples results in improved sensitivity and efficiency when compared to conventional static HS sampling. A 22 gauge stainless steel, 51-mm needle packed with Tenax TA and Carboxen 1000 particles is used as the NTD. Three different HS-NTD sampling methodologies are evaluated and all give limits of detection for the target VOCs in the ng L⁻¹ range. Active (purge-and-trap) HS-NTD sampling is found to give the best sensitivity but requires exhaustive control of the sampling conditions. The use of the NTD to collect the headspace gas sample results in a combined adsorption/desorption mechanism. The testing of different temperatures for the HS thermostating reveals a greater desorption effect when the sample is allowed to diffuse, whether passively or actively, through the sorbent particles. The limits of detection obtained in the simplest sampling methodology, static HS-NTD (5 mL aqueous sample in 20 mL HS vials, thermostating at 50 °C for 30 min with agitation), are sufficiently low as to permit its application to the analysis of 18 priority VOCs in natural and waste waters. In all cases compounds were detected below regulated levels. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Dynamic headspace-gas-chromatography-olfactometry analysis of different anatomical parts of lovage (Levisticum officinale Koch.) at eight growing stages

    NARCIS (Netherlands)

    Bylaite, E.; Roozen, J.P.; Legger, A.; Venskutonis, R.P.; Posthumus, M.A.

    2000-01-01

    Volatiles of five different parts of lovage (leaves, stems, flowers, seeds, and roots) were isolated by dynamic headspace (DHS) method and analyzed by GC-FID and GC-olfactometry (GC-O) techniques. In total, 98 compounds were identified in the samples, of which 41 are reported as lovage volatiles for

  5. Quantification of Polyfunctional Thiols in Wine by HS-SPME-GC-MS Following Extractive Alkylation

    Directory of Open Access Journals (Sweden)

    Lauren E. Musumeci

    2015-07-01

    Full Text Available Analyses of key odorous polyfunctional volatile thiols in wines (3-mercaptohexanol (3-MH, 3-mercaptohexylacetate (3-MHA, and 4-mercapto-4-methyl-2-pentanone (4-MMP are challenging due to their high reactivity and ultra-trace concentrations, especially when using conventional gas-chromatography electron impact mass spectrometry (GC-EI-MS. We describe a method in which thiols are converted to pentafluorobenzyl (PFB derivatives by extractive alkylation and the organic layer is evaporated prior to headspace solid phase microextraction (HS-SPME and GC-EI-MS analysis. Optimal parameters were determined by response surface area modeling. The addition of NaCl solution to the dried SPME vials prior to extraction resulted in up to less than fivefold improvement in detection limits. Using 40 mL wine samples, limits of detection for 4-MMP, 3-MH, and 3-MHA were 0.9 ng/L, 1 ng/L, and 17 ng/L, respectively. Good recovery (90%–109% and precision (5%–11% RSD were achieved in wine matrices. The new method was used to survey polyfunctional thiol concentrations in 61 commercial California and New York State wines produced from V. vinifera (Riesling, Gewürztraminer, Cabernet Sauvignon, Sauvignon blanc and non-varietal rosé wines, V. labruscana (Niagara, and Vitis spp. (Cayuga White. Mean 4-MMP concentrations in New York Niagara (17 ng/L were not significantly different from concentrations in Sauvignon blanc, but were significantly higher than 4-MMP in other varietal wines.

  6. Differentiation of Commercial PDO Wines Produced in Istria (Croatia According to Variety and Harvest Year Based on HS-SPME-GC/MS Volatile Aroma Compound Profiling

    Directory of Open Access Journals (Sweden)

    Igor Lukić

    2017-01-01

    Full Text Available To differentiate monovarietal wines made from native and introduced varieties in Istria (Croatia, samples of Malvazija istarska, Chardonnay and Muscat yellow from two harvest years (2013 and 2014 were subjected to headspace solid-phase microextraction and gas chromatographic/mass spectrometric analysis (HS-SPME-GC/MS of volatile aroma compounds. Significant effects of variety and harvest year were determined, but their interaction complicated the differentiation. Particular compounds were consistent as markers of variety in both years: nerol for Malvazija, ethyl cinnamate and a tentatively identified isomer of dimethylbenzaldehyde for Chardonnay, and terpenes for Muscat yellow. Wines from 2013 contained higher concentrations of the majority of important volatiles. A 100 % correct differentiation of Malvazija istarska and Chardonnay wines according to both variety and harvest year was achieved by stepwise linear discriminant analysis.

  7. Differentiation of Commercial PDO Wines Produced in Istria (Croatia) According to Variety and Harvest Year Based on HS-SPME-GC/MS Volatile Aroma Compound Profiling.

    Science.gov (United States)

    Lukić, Igor; Horvat, Ivana

    2017-03-01

    To differentiate monovarietal wines made from native and introduced varieties in Istria (Croatia), samples of Malvazija istarska, Chardonnay and Muscat yellow from two harvest years (2013 and 2014) were subjected to headspace solid-phase microextraction and gas chromatographic/mass spectrometric analysis (HS-SPME-GC/MS) of volatile aroma compounds. Significant effects of variety and harvest year were determined, but their interaction complicated the differentiation. Particular compounds were consistent as markers of variety in both years: nerol for Malvazija, ethyl cinnamate and a tentatively identified isomer of dimethylbenzaldehyde for Chardonnay, and terpenes for Muscat yellow. Wines from 2013 contained higher concentrations of the majority of important volatiles. A 100% correct differentiation of Malvazija istarska and Chardonnay wines according to both variety and harvest year was achieved by stepwise linear discriminant analysis.

  8. Analysis of aroma compounds of Roselle by Dynamic Headspace Sampling using different preparation methods

    DEFF Research Database (Denmark)

    Juhari, Nurul Hanisah Binti; Varming, Camilla; Petersen, Mikael Agerlin

    2015-01-01

    The influence of different methods of sample preparation on the aroma profiles of dried Roselle (Hibiscus sabdariffa) was studied. Least amounts of aroma compounds were recovered by analysis of whole dry calyxes (WD) followed by ground dry (GD), blended together with water (BTW), and ground...

  9. Detection of Pseudomonas aeruginosa in sputum headspace through volatile organic compound analysis

    Directory of Open Access Journals (Sweden)

    Goeminne Pieter C

    2012-10-01

    Full Text Available Abstract Introduction Chronic pulmonary infection is the hallmark of Cystic Fibrosis lung disease. Searching for faster and easier screening may lead to faster diagnosis and treatment of Pseudomonas aeruginosa (P. aeruginosa. Our aim was to analyze and build a model to predict the presence of P. aeruginosa in sputa. Methods Sputa from 28 bronchiectatic patients were used for bacterial culturing and analysis of volatile compounds by gas chromatography–mass spectrometry. Data analysis and model building were done by Partial Least Squares Regression Discriminant analysis (PLS-DA. Two analysis were performed: one comparing P. aeruginosa positive with negative cultures at study visit (PA model and one comparing chronic colonization according to the Leeds criteria with P. aeruginosa negative patients (PACC model. Results The PA model prediction of P. aeruginosa presence was rather poor, with a high number of false positives and false negatives. On the other hand, the PACC model was stable and explained chronic P. aeruginosa presence for 95% with 4 PLS-DA factors, with a sensitivity of 100%, a positive predictive value of 86% and a negative predictive value of 100%. Conclusion Our study shows the potential for building a prediction model for the presence of chronic P. aeruginosa based on volatiles from sputum.

  10. A high area, porous and resistant platinized stainless steel fiber coated by nanostructured polypyrrole for direct HS-SPME of nicotine in biological samples prior to GC-FID quantification.

    Science.gov (United States)

    Abdolhosseini, Sana; Ghiasvand, Alireza; Heidari, Nahid

    2017-09-01

    The surface of a stainless steel fiber was made porous, resistant and cohesive using electrophoretic deposition and coated by the nanostructured polypyrrole using an amended in-situ electropolymerization method. The coated fiber was applied for direct extraction of nicotine in biological samples through a headspace solid-phase microextraction (HS-SPME) method followed by GC-FID determination. The effects of the important experimental variables on the efficiency of the developed HS-SPME-GC-FID method, including pH of sample solution, extraction temperature and time, stirring rate, and ionic strength were evaluated and optimized. Under the optimal experimental conditions, the calibration curve was linear over the range of 0.1-20μgmL -1 and the detection limit was obtained 20ngmL -1 . Relative standard deviation (RSD, n=6) was calculated 7.6%. The results demonstrated the superiority of the proposed fiber compared with the most used commercial types. The proposed HS-SPME-GC-FID method was successfully used for the analysis of nicotine in urine and human plasma samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. A salting out system for improving the efficiency of the headspace solid-phase microextraction of short and medium chain free fatty acids.

    Science.gov (United States)

    Fiorini, Dennis; Pacetti, Deborah; Gabbianelli, Rosita; Gabrielli, Serena; Ballini, Roberto

    2015-08-28

    Given the importance of short and medium chain free fatty acids (FFAs) in several fields, this study sought to improve the extraction efficiency of the solid-phase microextraction (SPME) of FFAs by evaluating salting out agents that appear promising for this application. The salts ammonium sulfate ((NH4)2SO4) and sodium dihydrogen phosphate (NaH2PO4) were tried on their own and in combination (3.7/1), in four different total amounts, as salting out agents in the headspace-SPME-gas chromatographic (HS-SPME-GC) analysis of the FFAs from acetic acid (C2) to decanoic acid (C10). Their performance in a model system of an aqueous standard mixture of FFAs at a pH of 3.5 was compared to that of the more commonly used sodium chloride (NaCl) and sodium sulfate (Na2SO4). All of the salts and salt systems evaluated, in proper amount, gave improved results compared to NaCl (saturated), which instead gave interesting results only for the least volatile FFAs C8 and C10. For C2-C6, the salt system that gave the best results compared to NaCl was (NH4)2SO4/NaH2PO4, in the highest of the four amounts evaluated, with factor increases between 1.2 and 4.1-fold, and NaH2PO4, between 1.0 and 4.3-fold. The SPME extraction efficiency given by the mixture (NH4)2SO4/NaH2PO4 was also assessed on biological and food samples, confirming that overall it performed better than NaCl. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Characterisation of volatile profiles in 50 native Peruvian chili pepper using solid phase microextraction-gas chromatography mass spectrometry (SPME-GCMS).

    Science.gov (United States)

    Patel, Kirti; Ruiz, Candy; Calderon, Rosa; Marcelo, Mavel; Rojas, Rosario

    2016-11-01

    The volatiles were characterised by headspace solid phase micro extraction (HS-SPME), gas chromatography mass spectrometry (GC-FID/MS). A total of 127 compounds were identified with terpenes (including mono terpenes and sesquiterpenes - a total of 45 compounds), esters (31 compounds) and hydrocarbons (20 compounds) were the predominant volatile compounds. Principal component analysis (PCA) of the volatile compounds yielded 2 significant PC's, which together accounted for 90.3% of the total variance in the data set and the scatter plot generated between PC1 and PC2 successfully segregated the 50 chili pepper samples into 7 groups. Clusters of hydrocarbons, esters, terpenes, aldehyde and ketones formed the major determinants of the difference. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Evaluation and application of static headspace-multicapillary column-gas chromatography-ion mobility spectrometry for complex sample analysis.

    Science.gov (United States)

    Denawaka, Chamila J; Fowlis, Ian A; Dean, John R

    2014-04-18

    An evaluation of static headspace-multicapillary column-gas chromatography-ion mobility spectrometry (SHS-MCC-GC-IMS) has been undertaken to assess its applicability for the determination of 32 volatile compounds (VCs). The key experimental variables of sample incubation time and temperature have been evaluated alongside the MCC-GC variables of column polarity, syringe temperature, injection temperature, injection volume, column temperature and carrier gas flow rate coupled with the IMS variables of temperature and drift gas flow rate. This evaluation resulted in six sets of experimental variables being required to separate the 32 VCs. The optimum experimental variables for SHS-MCC-GC-IMS, the retention time and drift time operating parameters were determined; to normalise the operating parameters, the relative drift time and normalised reduced ion mobility for each VC were determined. In addition, a full theoretical explanation is provided on the formation of the monomer, dimer and trimer of a VC. The optimum operating condition for each VC calibration data was obtained alongside limit of detection (LOD) and limit of quantitation (LOQ) values. Typical detection limits ranged from 0.1ng bis(methylthio)methane, ethylbutanoate and (E)-2-nonenal to 472ng isovaleric acid with correlation coefficient (R(2)) data ranging from 0.9793 (for the dimer of octanal) through to 0.9990 (for isobutyric acid). Finally, the developed protocols were applied to the analysis of malodour in sock samples. Initial work involved spiking an inert matrix and sock samples with appropriate concentrations of eight VCs. The average recovery from the inert matrix was 101±18% (n=8), while recoveries from the sock samples were lower, that is, 54±30% (n=8) for sock type 1 and 78±24% (n=6) for sock type 2. Finally, SHS-MCC-GC-IMS was applied to sock malodour in a field trial based on 11 volunteers (mixed gender) over a 3-week period. By applying the SHS-MCC-GC-IMS database, four VCs were

  14. Determination of chlorophenols in landfill leachate using headspace sampling with ionic liquid-coated solid-phase microextraction fibers combined with gas chromatography–mass spectrometry

    International Nuclear Information System (INIS)

    Ho, Tse-Tsung; Chen, Chung-Yu; Li Zuguang; Yang, Thomas Ching-Cherng; Lee, Maw-Rong

    2012-01-01

    Highlights: ► Ionic liquid (IL), ([C 4 MIM][PF 6 ]), was rapid synthesized by microwave radiation. ► Trace chlorophenols in landfill leachate were extract by SPME coated IL. ► The IL-coated SPME-GC/MS method is low-cost, solvent-free and sensitive. - Abstract: A new microextraction technique based on ionic liquid solid-phase microextraction (IL-SPME) was developed for determination of trace chlorophenols (CPs) in landfill leachate. The synthesized ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([C 4 MIM][PF 6 ]), was coated onto the spent fiber of SPME for extraction of trace CPs. After extraction, the absorbed analytes were desorbed and quantified using gas chromatography–mass spectrometry (GC/MS). The term of the proposed method is as ionic liquid-coated of solid-phase microextraction combined with gas chromatography–mass spectrometry (IL-SPME-GC/MS). No carryover effect was found, and every laboratory-made ionic liquids-coated-fiber could be used for extraction at least eighty times without degradation of efficiency. The chlorophenols studied were 2,4-dichlorophenol (2,4-DP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP), and pentachlorophenol (PCP). The best results of chlorophenols analysis were obtained with landfill leachate at pH 2, headspace extraction for 4 min, and thermal desorption with the gas chromatograph injector at 240 °C for 4 min. Linearity was observed from 0.1 to 1000 μg L −1 with relative standard deviations (RSD) less than 7% and recoveries were over 87%. The limit of detection (LOD) for pentachlorophenol was 0.008 μg L −1 . The proposed method was tested by analyzing landfill leachate from a sewage farm. The concentrations of chlorophenols were detected to range from 1.1 to 1.4 μg L −1 . The results demonstrate that the IL-SPME-GC/MS method is highly effective in analyzing trace chlorophenols in landfill leachate.

  15. Determination of chlorophenols in landfill leachate using headspace sampling with ionic liquid-coated solid-phase microextraction fibers combined with gas chromatography-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Tse-Tsung; Chen, Chung-Yu [Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan (China); Li Zuguang [Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan (China); College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, Zhejiang (China); Yang, Thomas Ching-Cherng [Department of Chemistry, National Kaohsiung Normal University, Kaohsiung 82444, Taiwan (China); Lee, Maw-Rong, E-mail: mrlee@dragon.nchu.edu.tw [Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan (China)

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer Ionic liquid (IL), ([C{sub 4}MIM][PF{sub 6}]), was rapid synthesized by microwave radiation. Black-Right-Pointing-Pointer Trace chlorophenols in landfill leachate were extract by SPME coated IL. Black-Right-Pointing-Pointer The IL-coated SPME-GC/MS method is low-cost, solvent-free and sensitive. - Abstract: A new microextraction technique based on ionic liquid solid-phase microextraction (IL-SPME) was developed for determination of trace chlorophenols (CPs) in landfill leachate. The synthesized ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([C{sub 4}MIM][PF{sub 6}]), was coated onto the spent fiber of SPME for extraction of trace CPs. After extraction, the absorbed analytes were desorbed and quantified using gas chromatography-mass spectrometry (GC/MS). The term of the proposed method is as ionic liquid-coated of solid-phase microextraction combined with gas chromatography-mass spectrometry (IL-SPME-GC/MS). No carryover effect was found, and every laboratory-made ionic liquids-coated-fiber could be used for extraction at least eighty times without degradation of efficiency. The chlorophenols studied were 2,4-dichlorophenol (2,4-DP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP), and pentachlorophenol (PCP). The best results of chlorophenols analysis were obtained with landfill leachate at pH 2, headspace extraction for 4 min, and thermal desorption with the gas chromatograph injector at 240 Degree-Sign C for 4 min. Linearity was observed from 0.1 to 1000 {mu}g L{sup -1} with relative standard deviations (RSD) less than 7% and recoveries were over 87%. The limit of detection (LOD) for pentachlorophenol was 0.008 {mu}g L{sup -1}. The proposed method was tested by analyzing landfill leachate from a sewage farm. The concentrations of chlorophenols were detected to range from 1.1 to 1.4 {mu}g L{sup -1}. The results demonstrate that the IL-SPME-GC/MS method is highly effective in

  16. Analysis of volatile organic compounds in pleural effusions by headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry.

    Science.gov (United States)

    Huang, Zhongping; Zhang, Jie; Zhang, Peipei; Wang, Hong; Pan, Zaifa; Wang, Lili

    2016-07-01

    Headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry was applied to the analysis of volatile organic compounds in pleural effusions. The highly volatile organic compounds were separated successfully with high sensitivity by the employment of a cryotrap device, with the construction of a cold column head by freezing a segment of metal capillary with liquid nitrogen. A total of 76 volatile organic compounds were identified in 50 pleural effusion samples (20 malignant effusions and 30 benign effusions). Among them, 34 more volatile organic compounds were detected with the retention time less than 8 min, by comparing with the normal headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry method. Furthermore, 24 volatile organic compounds with high occurrence frequency in pleural effusion samples, 18 of which with the retention time less than 8 min, were selected for the comparative analysis. The results of average peak area comparison and box-plot analysis showed that except for cyclohexanone, 2-ethyl-1-hexanol, and tetramethylbenzene, which have been reported as potential cancer biomarkers, cyclohexanol, dichloromethane, ethyl acetate, n-heptane, ethylbenzene, and xylene also had differential expression between malignant and benign effusions. Therefore, the proposed approach was valuable for the comprehensive characterization of volatile organic compounds in pleural effusions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. ANALYTICAL APPROACH OF THE VOLATILE FRACTION OF Solanum quitoense BY HS-SPME/GC-MS

    Directory of Open Access Journals (Sweden)

    EDUARDO CORPAS IGUARÁN

    2017-07-01

    Full Text Available The species of lulo fruit (Solanum quitoense, predominant in Colombia, is a promising fruit for both national and international market due to its flavor and nutritional characteristics, which generated the interest to know the volatile composition of its pulp. After adjusting, the chromatographic conditions necessary to analyze volatile fraction of this fruit, the effect of the temperature and time of adsorption was measured through the headspace - solid phase microextraction (HS-SPME and gas chromatography - mass spectrometry (GC-MS, on the area of volatile compounds of S. quitoense, by applying the experimental design of a factor. The descriptive analysis suggested that the adsorption at 60°C and 30 minutes promoted optimal recovery of volatiles as well as internal standard (1-Octanol, with recovery of 99,66% at 60ºC, while the non-parametric test Kruskal-Wallis showed statistical differences in the effect of time (P= 0,018, but not of the temperature adsorption (P= 0,058 upon the volatiles compounds area. A predominance of esters (48,98%, aldehydes (18,37%, and alcohols (14,29% was observed and also were found compounds of greatest area such as 3-hexen-1-ol acetate, acetic acid methyl ester, and acetic acid hexyl ester. These metabolites determine the characteristic aroma from lulo pulp and influence the consumer preference.

  18. Analysis of Odorants in Marking Fluid of Siberian Tiger (Panthera tigris altaica) Using Simultaneous Sensory and Chemical Analysis with Headspace Solid-Phase Microextraction and Multidimensional Gas Chromatography-Mass Spectrometry-Olfactometry.

    Science.gov (United States)

    Soso, Simone B; Koziel, Jacek A

    2016-06-25

    Scent-marking is the most effective method of communication in the presence or absence of a signaler. These complex mixtures result in a multifaceted interaction triggered by the sense of smell. The objective was to identify volatile organic compound (VOC) composition and odors emitted by total marking fluid (MF) associated with Siberian tigers (Panthera tigris altaica). Siberian tiger, an endangered species, was chosen because its MF had never been analyzed. Solid phase microextraction (SPME) for headspace volatile collection combined with multidimensional gas chromatography-mass spectrometry-olfactometry for simultaneous chemical and sensory analyses were used. Thirty-two VOCs emitted from MF were identified. 2-acetyl-1-pyrroline, the sole previously identified compound responsible for the "characteristic" odor of P. tigris MF, was identified along with two additional compounds confirmed with standards (urea, furfural) and four tentatively identified compounds (3-methylbutanamine, (R)-3-methylcyclopentanone, propanedioic acid, and 3-hydroxybutanal) as being responsible for the characteristic aroma of Siberian tiger MF. Simultaneous chemical and sensory analyses improved characterization of scent-markings and identified compounds not previously reported in MF of other tiger species. This research will assist animal ecologists, behaviorists, and zookeepers in understanding how scents from specific MF compounds impact tiger and wildlife communication and improve management practices related to animal behavior. Simultaneous chemical and sensory analyses is applicable to unlocking scent-marking information for other species.

  19. Analysis of Odorants in Marking Fluid of Siberian Tiger (Panthera tigris altaica Using Simultaneous Sensory and Chemical Analysis with Headspace Solid-Phase Microextraction and Multidimensional Gas Chromatography-Mass Spectrometry-Olfactometry

    Directory of Open Access Journals (Sweden)

    Simone B. Soso

    2016-06-01

    Full Text Available Scent-marking is the most effective method of communication in the presence or absence of a signaler. These complex mixtures result in a multifaceted interaction triggered by the sense of smell. The objective was to identify volatile organic compound (VOC composition and odors emitted by total marking fluid (MF associated with Siberian tigers (Panthera tigris altaica. Siberian tiger, an endangered species, was chosen because its MF had never been analyzed. Solid phase microextraction (SPME for headspace volatile collection combined with multidimensional gas chromatography-mass spectrometry-olfactometry for simultaneous chemical and sensory analyses were used. Thirty-two VOCs emitted from MF were identified. 2-acetyl-1-pyrroline, the sole previously identified compound responsible for the “characteristic” odor of P. tigris MF, was identified along with two additional compounds confirmed with standards (urea, furfural and four tentatively identified compounds (3-methylbutanamine, (R-3-methylcyclopentanone, propanedioic acid, and 3-hydroxybutanal as being responsible for the characteristic aroma of Siberian tiger MF. Simultaneous chemical and sensory analyses improved characterization of scent-markings and identified compounds not previously reported in MF of other tiger species. This research will assist animal ecologists, behaviorists, and zookeepers in understanding how scents from specific MF compounds impact tiger and wildlife communication and improve management practices related to animal behavior. Simultaneous chemical and sensory analyses is applicable to unlocking scent-marking information for other species.

  20. Quantitative Analysis of Bisphenol A Leached from Household Plastics by Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry (SPME-GC-MS)

    Science.gov (United States)

    Johnson, Bettie Obi; Burke, Fernanda M.; Harrison, Rebecca; Burdette, Samantha

    2012-01-01

    The measurement of trace levels of bisphenol A (BPA) leached out of household plastics using solid-phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS) is reported here. BPA is an endocrine-disrupting compound used in the industrial manufacture of polycarbonate plastic bottles and epoxy resin can liners. This experiment…

  1. Multivariate statistical analysis of hemlock (Tsuga) volatiles by SPME/GC/MS: insights into the phytochemistry of the hemlock woolly adelgid (Adelges tsugae Annand)

    Science.gov (United States)

    Anthony Lagalante; Frank Calvosa; Michael Mirzabeigi; Vikram Iyengar; Michael Montgomery; Kathleen Shields

    2007-01-01

    A previously developed single-needle, SPME/GC/MS technique was used to measure the terpenoid content of T. canadensis growing in a hemlock forest at Lake Scranton, PA (Lagalante and Montgomery 2003). The volatile terpenoid composition was measured over a 1-year period from June 2003 to May 2004 to follow the annual cycle of foliage development from...

  2. HP-SPME of volatile polycyclic aromatic hydrocarbons from water using multiwalled carbon nanotubes coated on a steel fiber through electrophoretic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Maghsoudi, S.; Noroozian, E. [Shahid Bahonar Univ., Kerman (Iran, Islamic Republic of). Dept. of Chemistry

    2012-08-15

    A headspace solid-phase microextraction (SPME) method using a stainless steel wire electrophoretically coated with dodecylsulfate modified multiwalled carbon nanotubes was used for the gas chromatographic (GC) determination of polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Electrophoretic deposition was easily carried out from an aqueous sodium dodecylsulfate medium. The effects of various parameters on the efficiency of SPME process, such as extraction time, extraction temperature, ionic strength, desorption time, and desorption temperature were studied. Under optimized conditions, the detection limits for the various PAHs studied varied from 0.03 to 0.07 ng mL{sup -1}. The inter-day and intra-day relative standard deviations at a 10 ng mL{sup -1} concentration level (n = 7) using a single-fiber were from 5.5 to 9.7 and 4.1 to 8.5 %, respectively. The fiber-to-fiber RSD% (n = 3) was between 7.3 and 11.1 %. The linear ranges were between 0.1 and 100 ng mL{sup -1}. The method was successfully applied to the analysis of a real sample with the recoveries from 88 to 105 % for 5 ng mL{sup -1} and 89 to 101 % for 0.5 ng mL{sup -1} samples. (orig.)

  3. Determination of infinite dilution activity coefficients using HS-SPME/GC/FID for hydrocarbons in furfural at temperatures of (298.15, 308.15, and 318.15) K

    International Nuclear Information System (INIS)

    Arantes Furtado, Filipe; Vieira Coelho, Gerson Luiz

    2012-01-01

    Highlights: ► Two approaches were proposed using SPME on determination of infinite dilution activity coefficients. ► Infinite dilution activity coefficients of nine solutes in solvent furfural at T = (298.15, 308.15, and 318.15) K. ► Fiber–gas partition coefficients of nine solutes on PDMS at T = (298.15, 308.15, and 318.15) K. ► Optical microscopy analysis and statistical tests to measure possible damages on fiber coating. ► Advantages and limitations of methodology proposed were discussed. - Abstract: A new methodology using the headspace solid phase microextraction (HS-SPME) technique has been used to evaluate the infinite dilution activity coefficient (γ 12 ∞ ) of nine hydrocarbons (alkanes, cycloalkanes, and aromatics) in furfural solvent. The main objective of this study was to validate a faster and lower cost methodology expanding the use of HS-SPME to determine infinite dilution activity of solutes in organic solvents. Two approaches were proposed for the determination of γ 12 ∞ in order to use this technique (HS-SPME). In addition, the fiber–gas partition coefficients (K fg ) for each analyte at each of the studied temperatures were determined. The activity and partition coefficients have been reported at temperatures of (298.15, 308.15, and 318.15) K. The data were compared with the literature infinite dilution data determined by other methods such as liquid–gas chromatography (GLC) and gas stripping. Partial molar excess enthalpies of mixing at infinite dilution for each solute have been determined. The fibers were tested before and after each experiment, using statistical methods to ensure that their properties do not change during the experiments. The fibers were also analyzed by optical microscopy to evaluate possible surface damage by comparing them with new fibers. The activity coefficient values correlated well with the data in the literature and showed average deviations less than 10%.

  4. Development of the HS-SPME-GC-MS/MS method for analysis of chemical warfare agent and their degradation products in environmental samples.

    Science.gov (United States)

    Nawała, Jakub; Czupryński, Krzysztof; Popiel, Stanisław; Dziedzic, Daniel; Bełdowski, Jacek

    2016-08-24

    After World War II approximately 50,000 tons of chemical weapons were dumped in the Baltic Sea by the Soviet Union under the provisions of the Potsdam Conference on Disarmament. These dumped chemical warfare agents still possess a major threat to the marine environment and to human life. Therefore, continue monitoring of these munitions is essential. In this work, we present the application of new solid phase microextraction fibers in analysis of chemical warfare agents and their degradation products. It can be concluded that the best fiber for analysis of sulfur mustard and its degradation products is butyl acrylate (BA), whereas for analysis of organoarsenic compounds and chloroacetophenone, the best fiber is a co-polymer of methyl acrylate and methyl methacrylate (MA/MMA). In order to achieve the lowest LOD and LOQ the samples should be divided into two subsamples. One of them should be analyzed using a BA fiber, and the second one using a MA/MMA fiber. When the fast analysis is required, the microextraction should be performed by use of a butyl acrylate fiber because the extraction efficiency of organoarsenic compounds for this fiber is acceptable. Next, we have elaborated of the HS-SPME-GC-MS/MS method for analysis of CWA degradation products in environmental samples using laboratory obtained fibers The analytical method for analysis of organosulfur and organoarsenic compounds was optimized and validated. The LOD's for all target chemicals were between 0.03 and 0.65 ppb. Then, the analytical method developed by us, was used for the analysis of sediment and pore water samples from the Baltic Sea. During these studies, 80 samples were analyzed. It was found that 25 sediments and 5 pore water samples contained CWA degradation products such as 1,4-dithiane, 1,4-oxathiane or triphenylarsine, the latter being a component of arsine oil. The obtained data is evidence that the CWAs present in the Baltic Sea have leaked into the general marine environment. Copyright

  5. Comparison of extraction techniques and mass spectrometric ionization modes in the analysis of wine volatile carbonyls

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Julian; Mateo-Vivaracho, Laura; Cacho, Juan [Laboratory for Flavor Analysis and Enology, Institute of Engineering of Aragon, I3A, Department of Analytical Chemistry, Faculty of Sciences, University of Zaragoza, 50009 Zaragoza (Spain); Ferreira, Vicente, E-mail: vferre@unizar.es [Laboratory for Flavor Analysis and Enology, Institute of Engineering of Aragon, I3A, Department of Analytical Chemistry, Faculty of Sciences, University of Zaragoza, 50009 Zaragoza (Spain)

    2010-02-15

    This work presents a comparative study of the analytical characteristics of two methods for the analysis of carbonyl compounds in wine, both based on the derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). In the first method derivatives are formed in the solid phase extraction (SPE) cartridge in which the analytes have been previously isolated, while in the second method derivatives are formed in a solid phase microextraction (SPME) fibre saturated with vapors of the reagent and exposed to the sample headspace. In both cases detection has been carried out by electron impact (EI) or negative chemical ionization (NCI) mass spectrometry. The possibility of determining haloanisols simultaneously has been also considered. The method based on SPE presents, in general, better analytical properties than the SPME one. Although linearity was satisfactory for both methods (R{sup 2} > 0.99), repeatability of the SPE method (RSD < 10%) was better than that obtained with SPME (9% < RSD < 20%). Detection limits obtained with EI are better for the SPE method except for trihaloanisols, while with NCI detection limits for both strategies are comparable, although the SPME strategy presents worse results for ketones and methional. Detection limits are always lower with NCI, being the improvement most notable for SPME. Recovery experiments show that in the case of SPE, uncertainties are lower than 12% in all cases, while with the SPME method the imprecision plus the existence of matrix effects make the global uncertainty to be higher than 15%.

  6. Comparison of extraction techniques and mass spectrometric ionization modes in the analysis of wine volatile carbonyls

    International Nuclear Information System (INIS)

    Zapata, Julian; Mateo-Vivaracho, Laura; Cacho, Juan; Ferreira, Vicente

    2010-01-01

    This work presents a comparative study of the analytical characteristics of two methods for the analysis of carbonyl compounds in wine, both based on the derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). In the first method derivatives are formed in the solid phase extraction (SPE) cartridge in which the analytes have been previously isolated, while in the second method derivatives are formed in a solid phase microextraction (SPME) fibre saturated with vapors of the reagent and exposed to the sample headspace. In both cases detection has been carried out by electron impact (EI) or negative chemical ionization (NCI) mass spectrometry. The possibility of determining haloanisols simultaneously has been also considered. The method based on SPE presents, in general, better analytical properties than the SPME one. Although linearity was satisfactory for both methods (R 2 > 0.99), repeatability of the SPE method (RSD < 10%) was better than that obtained with SPME (9% < RSD < 20%). Detection limits obtained with EI are better for the SPE method except for trihaloanisols, while with NCI detection limits for both strategies are comparable, although the SPME strategy presents worse results for ketones and methional. Detection limits are always lower with NCI, being the improvement most notable for SPME. Recovery experiments show that in the case of SPE, uncertainties are lower than 12% in all cases, while with the SPME method the imprecision plus the existence of matrix effects make the global uncertainty to be higher than 15%.

  7. [Analysis of the components of floral scent in Glochidion puberum using gas chromatography-mass spectrometry with dynamic headspace adsorption].

    Science.gov (United States)

    Huang, Daihong; Zhang, Zhenguo; Chen, Guoping; Li, Houhun; Shi, Fuchen

    2015-03-01

    The floral scent plays the important key role in maintaining the obligate pollination mutualism between Glochidion plants and Epicephala moths. In the study, the dynamic headspace adsorption technique was employed to collect the floral scent emitted by Glochidion puberum, gas chromatography coupled with mass spectrometry (GC-MS) was used for the detection and identification of volatile chemical components in headspace samples of flowers from G. puberum. The peak area normalization was used to determine the relative contents of each odour component. The results showed that 45 compounds mainly consisting of monoterpenes and sesquiterpenes were isolated from the floral scent produced by G. puberum. Especially, both linalool (38.06%) and β-elemene (23.84%) were considered as the major scent components of G. puberum. It was speculated that linalool and β-elemene may be the two potential compounds attracting female Epicephala moths. The study provided the basic data for further electroantennographic detection and bioassays to identify the compounds having the actual physiological activity to female Epicephala moths.

  8. Analysis of volatile flavor compounds influencing Chinese-type soy sauces using GC-MS combined with HS-SPME and discrimination with electronic nose.

    Science.gov (United States)

    Gao, Lihua; Liu, Ting; An, Xinjing; Zhang, Jinlan; Ma, Xiaoran; Cui, Jinmei

    2017-01-01

    Soy sauce contains a variety of volatiles that are highly valuable to its quality with regard to sensory characteristics. This paper describes the analysis of volatile compounds influencing the flavor quality of Chinese-type soy sauces. Gas chromatography-mass spectrometry (GC-MS) combined with headspace-solid phase microextraction and electronic nose (E-nose) were applied for identifying the volatile flavor compounds as well as determining their volatile profiles of 12 soy sauces manufactured by different fermentation process. Forty one key volatile components of these 12 soy sauce products, a pure soy sauce and an acid-hydrolyzed vegetable protein sample, were compared in semi-quantitative form, and their volatile flavor profiles were analyzed by E-nose. The substantially similar results between hierarchical cluster analysis based on GC-MS data and E-nose analysis suggested that both techniques may be useful in evaluating the flavor quality of soy sauces and differentiating soy sauce products. The study also showed that there were less volatile flavor compounds in soy sauces produced through low-salt solid-state fermentation process, a traditional manufacturing technology and a widely adopted technology in Chinese soy sauce industries. In addition, the investigation suggested that the flavor quality of soy sauce varied widely in Chinese domestic market, and that the present Chinese national standards of soy sauce should be further perfected by the addition of flavor grades of soy sauce in the physical and chemical index. Meanwhile, this research provided valuable information to manufacturers and government regulators, which have practical significance to improve quality of soy sauces.

  9. Headspace solid-phase microextraction with 1-pyrenyldiazomethane on-fibre derivatisation for analysis of fluoroacetic acid in biological samples.

    Science.gov (United States)

    Sporkert, Frank; Pragst, Fritz; Hübner, Sandra; Mills, Graham

    2002-05-25

    A new and in part automated headspace solid-phase microextraction method for quantitative determination of the highly toxic rodenticide fluoroacetic acid (FAA) in serum and other biological samples has been developed. FAA and deuterated acetic acid (internal standard) were extracted from acidified samples by a StableFlex divinylbenzene-Carboxen on polydimethylsiloxane fibre. The acids were derivatised on the fibre in-situ with 1-pyrenyldiazomethane and detected using gas chromatography-mass spectrometry with electron impact ionisation and selected ion monitoring. The calibration curve for FAA in serum was linear over the range from 0.02 to 5 microg/ml, with limits of detection and quantification of 0.02 and 0.07 microg/ml, respectively. The method was also tested with spiked whole blood, urine, stomach contents and kidney samples. It was sufficiently reliable, reproducible and sensitive for use in routine forensic toxicology applications.

  10. Method for sampling and analysis of volatile biomarkers in process gas from aerobic digestion of poultry carcasses using time-weighted average SPME and GC-MS.

    Science.gov (United States)

    Koziel, Jacek A; Nguyen, Lam T; Glanville, Thomas D; Ahn, Heekwon; Frana, Timothy S; Hans van Leeuwen, J

    2017-10-01

    A passive sampling method, using retracted solid-phase microextraction (SPME) - gas chromatography-mass spectrometry and time-weighted averaging, was developed and validated for tracking marker volatile organic compounds (VOCs) emitted during aerobic digestion of biohazardous animal tissue. The retracted SPME configuration protects the fragile fiber from buffeting by the process gas stream, and it requires less equipment and is potentially more biosecure than conventional active sampling methods. VOC concentrations predicted via a model based on Fick's first law of diffusion were within 6.6-12.3% of experimentally controlled values after accounting for VOC adsorption to the SPME fiber housing. Method detection limits for five marker VOCs ranged from 0.70 to 8.44ppbv and were statistically equivalent (p>0.05) to those for active sorbent-tube-based sampling. The sampling time of 30min and fiber retraction of 5mm were found to be optimal for the tissue digestion process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Liquid paraffin as new dilution medium for the analysis of high boiling point residual solvents with static headspace-gas chromatography.

    Science.gov (United States)

    D'Autry, Ward; Zheng, Chao; Bugalama, John; Wolfs, Kris; Hoogmartens, Jos; Adams, Erwin; Wang, Bochu; Van Schepdael, Ann

    2011-07-15

    Residual solvents are volatile organic compounds which can be present in pharmaceutical substances. A generic static headspace-gas chromatography analysis method for the identification and control of residual solvents is described in the European Pharmacopoeia. Although this method is proved to be suitable for the majority of samples and residual solvents, the method may lack sensitivity for high boiling point residual solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and benzyl alcohol. In this study, liquid paraffin was investigated as new dilution medium for the analysis of these residual solvents. The headspace-gas chromatography method was developed and optimized taking the official Pharmacopoeia method as a starting point. The optimized method was validated according to ICH criteria. It was found that the detection limits were below 1μg/vial for each compound, indicating a drastically increased sensitivity compared to the Pharmacopoeia method, which failed to detect the compounds at their respective limit concentrations. Linearity was evaluated based on the R(2) values, which were above 0.997 for all compounds, and inspection of residual plots. Instrument and method precision were examined by calculating the relative standard deviations (RSD) of repeated analyses within the linearity and accuracy experiments, respectively. It was found that all RSD values were below 10%. Accuracy was checked by a recovery experiment at three different levels. Mean recovery values were all in the range 95-105%. Finally, the optimized method was applied to residual DMSO analysis in four different Kollicoat(®) sample batches. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. A headspace solid-phase microextraction procedure coupled with gas chromatography-mass spectrometry for the analysis of volatile polycyclic aromatic hydrocarbons in milk samples

    Energy Technology Data Exchange (ETDEWEB)

    Aguinaga, N.; Campillo, N.; Vinas, P.; Hernandez-Cordoba, M. [University of Murcia, Department of Analytical Chemistry, Faculty of Chemistry, Murcia (Spain)

    2008-06-15

    A sensitive and solvent-free method for the determination of ten polycyclic aromatic hydrocarbons, namely, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene and chrysene, with up to four aromatic rings, in milk samples using headspace solid-phase microextraction and gas chromatography-mass spectrometry detection has been developed. A polydimethylsiloxane-divinylbenzene fiber was chosen and used at 75 C for 60 min. Detection limits ranging from 0.2 to 5 ng L{sup -1} were attained at a signal-to-noise ratio of 3, depending on the compound and the milk sample under analysis. The proposed method was applied to ten different milk samples and the presence of six of the analytes studied in a skimmed milk with vegetal fiber sample was confirmed. The reliability of the procedure was verified by analyzing two different certified reference materials and by recovery studies. (orig.)

  13. Direct thermal desorption in the analysis of cheese volatiles by gas chromatography and gas chromatography-mass spectrometry: comparison with simultaneous distillation-extraction and dynamic headspace.

    Science.gov (United States)

    Valero, E; Sanz, J; Martínez-Castro, I

    2001-06-01

    Direct thermal desorption (DTD) has been used as a technique for extracting volatile components of cheese as a preliminary step to their gas chromatographic (GC) analysis. In this study, it is applied to different cheese varieties: Camembert, blue, Chaumes, and La Serena. Volatiles are also extracted using other techniques such as simultaneous distillation-extraction and dynamic headspace. Separation and identification of the cheese components are carried out by GC-mass spectrometry. Approximately 100 compounds are detected in the examined cheeses. The described results show that DTD is fast, simple, and easy to automate; requires only a small amount of sample (approximately 50 mg); and affords quantitative information about the main groups of compounds present in cheeses.

  14. Ultrafast Screening and Quantitation of Pesticides in Food and Environmental Matrices by Solid-Phase Microextraction-Transmission Mode (SPME-TM) and Direct Analysis in Real Time (DART).

    Science.gov (United States)

    Gómez-Ríos, Germán Augusto; Gionfriddo, Emanuela; Poole, Justen; Pawliszyn, Janusz

    2017-07-05

    The direct interface of microextraction technologies to mass spectrometry (MS) has unquestionably revolutionized the speed and efficacy at which complex matrices are analyzed. Solid Phase Micro Extraction-Transmission Mode (SPME-TM) is a technology conceived as an effective synergy between sample preparation and ambient ionization. Succinctly, the device consists of a mesh coated with polymeric particles that extracts analytes of interest present in a given sample matrix. This coated mesh acts as a transmission-mode substrate for Direct Analysis in Real Time (DART), allowing for rapid and efficient thermal desorption/ionization of analytes previously concentrated on the coating, and dramatically lowering the limits of detection attained by sole DART analysis. In this study, we present SPME-TM as a novel tool for the ultrafast enrichment of pesticides present in food and environmental matrices and their quantitative determination by MS via DART ionization. Limits of quantitation in the subnanogram per milliliter range can be attained, while total analysis time does not exceed 2 min per sample. In addition to target information obtained via tandem MS, retrospective studies of the same sample via high-resolution mass spectrometry (HRMS) were accomplished by thermally desorbing a different segment of the microextraction device.

  15. Further research on the photo-SPME of triclosan

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Prado, Lucia; Llompart, Maria; Lores, Marta; Fernandez-Alvarez, Maria; Garcia-Jares, Carmen; Cela, Rafael [Universidad de Santiago de Compostela, Departamento de Quimica Analitica, Nutricion y Bromatologia. Facultad de Quimica, Instituto de Investigacion y Analisis Alimentario, Santiago de Compostela (Spain)

    2006-04-15

    In this study the photoinduced degradation of triclosan has been investigated by photo-solid-phase microextraction (photo-SPME). In photo-SPME, photodegradation is carried out on the SPME fibre containing the target compound. Triclosan was extracted from aqueous solutions by use of polydimethylsiloxane SPME fibres and these were subsequently exposed to UV irradiation (power 8 W, wavelength 254 nm) for different times (from 2 to 60 min). The photodegradation kinetics of triclosan were investigated, the photoproducts generated were tentatively identified, and the photochemical behaviour of these products was studied by use of this on-fibre approach followed by gas chromatographic-mass spectrometric analysis. Eight photoproducts were tentatively identified, including chlorinated phenols, chlorohydroxydiphenyl ethers, 2,8-dichlorodibenzo-p-dioxin, and a possible dichlorodibenzodioxin isomer or dichlorohydroxydibenzofuran. The main photodegradation mechanisms were postulated and photodegradation pathways proposed. The effect of pH on triclosan degradation and on triclosan-to-dioxin conversion was also investigated. Triclosan degradation occurred, and generation of 2,8-dichlorodibenzo-p-dioxin was confirmed, throughout the pH range studied (from 3 to 9). (orig.)

  16. A short review of headspace extraction and ultrasonic solvent extraction for honey volatiles fingerprinting

    Directory of Open Access Journals (Sweden)

    Z. Marijanović

    2009-01-01

    Full Text Available Honey volatiles exhibit a potential role in distinguishing honeys as a function of botanical origin, but heating of honey generates artefacts such as compounds of Strecker degradation and Maillard reaction products. This short review is focused on the most recently applied methods for honey volatiles fingerprinting (without generation of thermal artefacts: headspace extraction (dynamic headspace extraction (DHE, headspace solid-phase microextraction (HS-SPME and ultrasonic solvent extraction (USE. These methods display a varying degree of selectivity and effectiveness depending upon the compounds involved and the extraction conditions. Recent developments of these methods are discussed, with application examples drawn from the literature as well from our own research. Flavour qualities of the honey are very much dependent on the volatile and semivolatile organic compounds present in both the sample matrix and the headspace aroma. Therefore the use of one single technique is not adequate for reliable honey volatiles profiling, but combined use of headspace extraction and ultrasonic solvent extraction could be a useful tool for the characterization of the honey and identification of its botanical source through typical volatile marker compounds.

  17. Headspace solid-phase microextraction coupled to gas chromatography for the analysis of aldehydes in edible oils.

    Science.gov (United States)

    Ma, Chunhua; Ji, Jiaojiao; Tan, Connieal; Chen, Dongmei; Luo, Feng; Wang, Yiru; Chen, Xi

    2014-03-01

    Oxidation has important effects on the quality of edible oils. In particular, the generation of aldehydes produced by the oxidation of oils is one of the deteriorative factors to their quality. The aim of this study was to develop a method to determine the aldehydes as lipid oxidation markers in edible oils. Seven aldehydes generated from lipid oxidation were studied using headspace solid-phase microextraction coupled to gas chromatography with a flame ionization detector. The extraction efficiency of five commercial fibers was investigated and the influence of extraction temperature, extraction time, desorption temperature, and desorption time were optimized. The best result was obtained with 85 μm carboxen/polydimethylsiloxane, extraction at 50 °C for 15 min and desorption in the gas chromatography injector at 250 °C for 2 min. Under the optimized conditions, the content of hexanal was the highest of the seven aldehydes in all edible oils. The limits of detection for hexanal in the three oils were found to range from 4.6 to 10.2 ng L(-1). The reproducibility of the method was evaluated and the relative standard deviations were less than 8.9%. This developed approach was successfully applied to analyze hexanal in peanut oil, soy oil, and olive oil samples, and these results were compared with those obtained using the thiobarbituric acid-reactive substances (TBARs) method. © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Magnetic solid phase extraction and static headspace gas chromatography-mass spectrometry method for the analysis of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Cai, Ying; Yan, Zhihong; Wang, Lijia; NguyenVan, Manh; Cai, Qingyun

    2016-01-15

    A magnetic solid phase extraction (MSPE) protocol combining a static headspace gas chromatography coupled to mass spectrometry (HS-GC-MS) method has been developed for extraction, and determination of 16 polycyclic aromatic hydrocarbons (PAHs) in drinking water samples. Magnetic nanoparticles (MNPs) were coated with 3-aminopropyltriethoxysilane and modified by cholesterol chloroformate. Transmission electron microscope, vibrating sample magnetometer, Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy were used to characterize the cholesterol-functionalized sorbents, and the main parameters affecting the extraction as well as HS sampling, such as sorbent amount, extraction time, oven temperature and equilibration time have been investigated and established. Combination with HS sampling, the MSPE procedure was simple, fast and environmentally friendly, without need of any organic solvent. Method validation proved the feasibility of the developed sorbents for the quantitation of the investigated analytes at trace levels obtaining the limit of detection (S/N=3) ranging from 0.20 to 7.8 ng/L. Good values for intra and inter-day precision were obtained (RSDs ≤ 9.9%). The proposed method was successfully applied to drinking water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Novel polyamide-based nanofibers prepared by electrospinning technique for headspace solid-phase microextraction of phenol and chlorophenols from environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Bagheri, Habib, E-mail: bagheri@sharif.edu [Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, Azadi Av., P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of); Aghakhani, Ali; Baghernejad, Masoud; Akbarinejad, Alireza [Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, Azadi Av., P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)

    2012-02-24

    A novel solid phase microextraction (SPME) fiber was fabricated by electrospinning method in which a polymeric solution was converted to nanofibers using high voltages. A thin stainless steel wire was coated by the network of polymeric nanofibers. The polymeric nanofiber coating on the wire was mechanically stable due to the fine and continuous nanofibers formation around the wire with a three dimensional structure. Polyamide (nylon 6), due to its suitable characteristics was used to prepare the unbreakable SPME nanofiber. The scanning electron microscopy (SEM) images of this new coating showed a diameter range of 100-200 nm for polyamide nanofibers with a homogeneous and porous surface structure. The extraction efficiency of new coating was investigated for headspace solid-phase microextraction (HS-SPME) of some environmentally important chlorophenols from aqueous samples followed by gas chromatography-mass spectrometry (GC-MS) analysis. Effect of different parameters influencing the extraction efficiency including extraction temperature, extraction time, ionic strength and polyamide amount were investigated and optimized. In order to improve the chromatographic behavior of phenolic compounds, all the analytes were derivatized prior to the extraction process using basic acetic anhydride. The detection limits of the method under optimized conditions were in the range of 2-10 ng L{sup -1}. The relative standard deviations (RSD) (n = 3) at the concentration level of 1.7-6.7 ng mL{sup -1} were obtained between 1 and 7.4%. The calibration curves of chlorophenols showed linearity in the range of 27-1330 ng L{sup -1} for phenol and monochlorophenols and 7-1000 ng L{sup -1} for dichloro and trichlorophenols. Also, the proposed method was successfully applied to the extraction of phenol and chlorophenols from real water samples and relative recoveries were between 84 and 98% for all the selected analytes except for 2,4,6 tricholophenol which was between 72 and 74%.

  20. Novel polyamide-based nanofibers prepared by electrospinning technique for headspace solid-phase microextraction of phenol and chlorophenols from environmental samples

    International Nuclear Information System (INIS)

    Bagheri, Habib; Aghakhani, Ali; Baghernejad, Masoud; Akbarinejad, Alireza

    2012-01-01

    A novel solid phase microextraction (SPME) fiber was fabricated by electrospinning method in which a polymeric solution was converted to nanofibers using high voltages. A thin stainless steel wire was coated by the network of polymeric nanofibers. The polymeric nanofiber coating on the wire was mechanically stable due to the fine and continuous nanofibers formation around the wire with a three dimensional structure. Polyamide (nylon 6), due to its suitable characteristics was used to prepare the unbreakable SPME nanofiber. The scanning electron microscopy (SEM) images of this new coating showed a diameter range of 100–200 nm for polyamide nanofibers with a homogeneous and porous surface structure. The extraction efficiency of new coating was investigated for headspace solid-phase microextraction (HS-SPME) of some environmentally important chlorophenols from aqueous samples followed by gas chromatography–mass spectrometry (GC–MS) analysis. Effect of different parameters influencing the extraction efficiency including extraction temperature, extraction time, ionic strength and polyamide amount were investigated and optimized. In order to improve the chromatographic behavior of phenolic compounds, all the analytes were derivatized prior to the extraction process using basic acetic anhydride. The detection limits of the method under optimized conditions were in the range of 2–10 ng L −1 . The relative standard deviations (RSD) (n = 3) at the concentration level of 1.7–6.7 ng mL −1 were obtained between 1 and 7.4%. The calibration curves of chlorophenols showed linearity in the range of 27–1330 ng L −1 for phenol and monochlorophenols and 7–1000 ng L −1 for dichloro and trichlorophenols. Also, the proposed method was successfully applied to the extraction of phenol and chlorophenols from real water samples and relative recoveries were between 84 and 98% for all the selected analytes except for 2,4,6 tricholophenol which was between 72 and 74%.

  1. Preparation and characterization of sodium dodecyl sulfate doped polypyrrole solid phase micro extraction fiber and its application to endocrine disruptor pesticide analysis.

    Science.gov (United States)

    Korba, Korcan; Pelit, Levent; Pelit, Füsun Okçu; Ozdokur, K Volkan; Ertaş, Hasan; Eroğlu, Ahmet E; Ertaş, F Nil

    2013-06-15

    A robust in house solid-phase micro extraction (SPME) surface has been developed for the headspace (HS)-SPME determination of endocrine disruptor pesticides, namely, Chlorpyrifos, Penconazole, Procymidone, Bromopropylate and Lambda-Cyhalothrin in wine sample by using sodium dodecylsulfate doped polypyrrole SPME fiber. Pyrrole monomer was electrochemically polymerized on a stainless steel wire in laboratory conditions in virtue of diminishing the cost and enhancing the analyte retention on its surface to exert better selectivity and hence the developed polymerized surface could offer to analyst to exploit it as a fiber in headspace SPME analysis. The parameters, mainly, adsorption temperature and time, desorption temperature, stirring rate and salt amount were optimized to be as 70°C and 45min, 200°C, 600rpm and 10gL(-1), respectively. Limit of detection was estimated in the range of 0.073-1.659ngmL(-1) for the pesticides studied. The developed method was applied in to red wine sample with acceptable recovery values (92-107%) which were obtained for these selected pesticides. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Measurement of Activity Coefficients at Infinite Dilution for Alcohols in [BMIM][CH3SO4] using HS-SPME/GC-FID

    Directory of Open Access Journals (Sweden)

    A. M. Elias

    Full Text Available ABSTRACT The activity coefficient at infinite dilution (&IN1 and distribution ratios at infinite dilution (&IN2 were determined for alkanols (methanol, ethanol, 1-propanol, 1-butanol, 2-butanol, and 2-methyl-2-propanol in the ionic liquid (IL 1-butyl-3-methylimidazolium methyl sulfate ([BMIM][CH3SO4] by HS-SPME (Headspace - Solid Phase Micro Extraction at four temperatures (298.15, 313.15, 333.15, and 353.15K using headspace - solid phase microextraction (SPME-HS. The results showed significant agreement with literature data. In addition, partial molar excess enthalpies at infinite dilution (&IN3, excess Gibbs energies (&IN4, and excess entropies (&IN5 were calculated from the (&IN6 values.

  3. Investigations on the emission of fragrance allergens from scented toys by means of headspace solid-phase microextraction gas chromatography-mass spectrometry.

    Science.gov (United States)

    Masuck, Ines; Hutzler, Christoph; Luch, Andreas

    2010-04-30

    In the revised European toy safety directive 2009/48/EC the application of fragrance allergens in children's toys is restricted. The focus of the present work lies on the instrumental analytics of 13 banned fragrance allergens, as well as on 11 fragrance allergens that require declaration when concentrations surpass 100 microg per gram material. Applying a mixture of ethyl acetate and toluene solid/liquid extraction was performed prior to quantitative analysis of mass contents of fragrances in scented toys. In addition, an easy-to-perform method for the determination of emitted fragrances at 23 degrees C (handling conditions) or at 40 degrees C (worst case scenario) has been worked out to allow for the evaluation of potential risks originating from inhalation of these compounds during handling of or playing with toys. For this purpose a headspace solid-phase microextraction (HS-SPME) technique was developed and coupled to subsequent gas chromatography-mass spectrometry (GC-MS) analysis. Fragrance allergens were adsorbed (extracted) from the gas phase onto an 85 microm polyacrylate fiber while incubating pieces of the scented toys in sealed headspace vials at 23 degrees C and 40 degrees C. Quantification of compounds was performed via external calibration. The newly developed headspace method was subsequently applied to five perfumed toys. As expected, the emission of fragrance allergens from scented toys depends on the temperature and on the content of fragrance allergens present in those samples. In particular at conditions mimicking worst case (40 degrees C), fragrance allergens in toys may pose a risk to children since considerable amounts of compound might be absorbed by lung tissue via breathing of contaminated air. 2010 Elsevier B.V. All rights reserved.

  4. Characterization of Volatile Compounds with HS-SPME from Oxidized n-3 PUFA Rich Oils via Rancimat Tests.

    Science.gov (United States)

    Yang, Kai-Min; Cheng, Ming-Ching; Chen, Chih-Wei; Tseng, Chin-Yin; Lin, Li-Yun; Chiang, Po-Yuan

    2017-02-01

    Algae oil and fish oil are n-3 PUFA mainstream commercial products. The various sources for the stability of n-3 PUFA oxidation are influenced by the fatty acid composition, extraction and refined processing. In this study, the oil stability index (OSI) occurs within 2.3 to 7.6 hours with three different n-3 PUFA rich oil. To set the OSI in the Rancimat test as the oil stability limit and observed various degrees of oxidation (0, 25, 50, 75, 100 and 125%). The volatile oxidation compounds were analyzed via headspace-solid phase microextraction (HS-SPME) and GC/MS. We detected 51 volatile compound variations during the oxidation, which were composed of aldehydes, hydrocarbons, cyclic compounds, alcohols, benzene compounds, ketones, furans, ester and pyrrolidine. The off-flavor characteristics can be strongly influenced by the synergy effects of volatile oxidation compounds. Chemometric analysis (PCA and AHC) was applied to identify the sensitive oxidation marker compounds, which included a (E,E)-2,4-heptadienal appropriate marker, via lipid oxidation in the n-3 PUFA rich oil.

  5. Natural Variation of Volatile Compounds in Virgin Olive Oil Analyzed by HS-SPME/GC-MS-FID

    Directory of Open Access Journals (Sweden)

    Carlos Sanz

    2018-04-01

    Full Text Available Virgin olive oil is unique among plant oils for its high levels of oleic acid, and the presence of a wide range of minor components, which are responsible for both its health-promoting properties and characteristic aroma, and only produced when olives are crushed during the industrial process used for oil production. The genetic variability of the major volatile compounds comprising the oil aroma was studied in a representative sample of olive cultivars from the World Olive Germplasm Collection (IFAPA, Cordoba, Spain, by means of the headspace solid-phase microextraction/gas chromatography–mass spectrometry–flame ionization detection (HS-SPME/GC-MS-FID. The analytical data demonstrated that a high variability is found for the content of volatile compounds in olive species, and that most of the volatile compounds found in the oils were synthesized by the enzymes included in the so-called lipoxygenase pathway. Multivariate analysis allowed the identification of cultivars that are particularly interesting, in terms of volatile composition and presumed organoleptic quality, which can be used both to identify old olive cultivars that give rise to oils with a high organoleptic quality, and in parent selection for olive breeding programs.

  6. NMR, HS-SPME-GC/MS, and HPLC/MSn Analyses of Phytoconstituents and Aroma Profile of Rosmarinus eriocalyx.

    Science.gov (United States)

    Bendif, Hamdi; Miara, Mohamed Djamel; Peron, Gregorio; Sut, Stefania; Dall'Acqua, Stefano; Flamini, Guido; Maggi, Filippo

    2017-10-01

    In this work, a comprehensive study on the chemical constituents of the aerial parts of Rosmarinus eriocalyx (Lamiaceae), an aromatic shrub traditionally consumed as a food and herbal remedy in Algeria, is presented. The aroma profile was analysed by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC/MS), whereas the crude extract constituents were analyzed by 1 H-NMR and by high performance liquid chromatography coupled with mass spectrometry (HPLC/MS n ). Thirty-nine volatile compounds, most of them being monoterpenes, have been identified, with camphor, camphene, and α-pinene as the most abundant constituents. 1 H-NMR analysis revealed the presence of phenolic compounds and betulinic acid while HPLC/MS n allowed the identification of glycosilated and aglyconic flavonoids as well as phenylpropanoid derivatives. Some of these constituents, namely as betulinic acid, rosmanol, and cirsimaritin were reported for the first time in R. eriocalyx. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  7. Differentiation of wines according to grape variety and geographical origin based on volatiles profiling using SPME-MS and SPME-GC/MS methods.

    Science.gov (United States)

    Ziółkowska, Angelika; Wąsowicz, Erwin; Jeleń, Henryk H

    2016-12-15

    Among methods to detect wine adulteration, profiling volatiles is one with a great potential regarding robustness, analysis time and abundance of information for subsequent data treatment. Volatile fraction fingerprinting by solid-phase microextraction with direct analysis by mass spectrometry without compounds separation (SPME-MS) was used for differentiation of white as well as red wines. The aim was to differentiate between varieties used for wine production and to also differentiate wines by country of origin. The results obtained were compared to SPME-GC/MS analysis in which compounds were resolved by gas chromatography. For both approaches the same type of statistical procedure was used to compare samples: principal component analysis (PCA) followed by linear discriminant analysis (LDA). White wines (38) and red wines (41) representing different grape varieties and various regions of origin were analysed. SPME-MS proved to be advantageous in use due to better discrimination and higher sample throughput. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Comparison and characterization of volatile compounds as markers of oils stability during frying by HS-SPME-GC/MS and Chemometric analysis.

    Science.gov (United States)

    Ben Hammouda, Ibtissem; Freitas, Flavia; Ammar, Sonda; Da Silva, M D R Gomes; Bouaziz, Mohamed

    2017-11-15

    The formation and emission of volatile compounds, including the aldehydes and some toxic compounds of oil samples, ROPO pure (100%) and the blended ROPO/RCO (80-20%), were carried out during deep frying at 180°C. The volatile profile of both oil samples was evaluated by an optimized HS-SPME-GC/MS method, before and after 20, 40 and 60 successive sessions of deep-frying. Actually, from 100 detected compounds, aldehydes were found to be the main group formed. In addition, the oil degradation under thermal treatment regarding the volatile compounds were evaluated and compared. Consequently, the blended ROPO/RCO revealed fewer formations of unsaturated aldehydes, including toxic ones, such as acrolein, and showed a greater stability against oxidative thermal degradation compared to ROPO pure. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Optimization of Solid Phase Micro-Extraction (SPME for Monitoring Occupational Exposure to Ethyl Benzene

    Directory of Open Access Journals (Sweden)

    H. Heidari

    2009-08-01

    Full Text Available AbstractBackground and Objectives: Analytical methods for volatile organic compounds (VOCs in different samples need extraction of compounds, by applying hazardous solvents. Solid phase micro-extraction (SPME is a solvent-free equilibrium extraction method, in which proper calibration can allow quantitative determinations of VOCs at a very good sensitivity without the use of any organic solvent. VOCs are generally present in urine only at trace levels, therefore, a sensitive procedure is needed for their trace determinations. Throughout this study, headspace solid phase micro-extraction (HS-SPME was followed by GC-FID for ethyl benzene in spiked urine was optimized.Methods: In this study, the parameters influencing SPME and gas chromatography of ethyl benzene, including extraction time, temperature, desorption temperature, desorption time, salt addition, sample pH, sample volume and sample agitation were investigated. Results: Extraction procedure was performed at 30°C for 6 min, using 0.2 gml-1 of NaCl in the sample solution. The sample volume and sample pH were optimized at 5 ml and 7 (neutral pH, respectively. Desorption of the ethyl benzene was carried out for 60 sec. at 250°C. The method was also validated with three different spiked urine samples and illustrated an appropriate reproducibility over six consecutive days as well as six within-day experiments. During this investigation, parameters of accuracy, linearity, and detection limits of the procedure were also evaluated.Conclusion: The developed method of HS- SPME-GC-FID proved to be a simple, convenient, and practical procedure, and was successfully used for measuring of ethyl benzene in spiked urine.

  10. Full evaporation dynamic headspace and gas chromatography-mass spectrometry for uniform enrichment of odor compounds in aqueous samples.

    Science.gov (United States)

    Ochiai, Nobuo; Sasamoto, Kikuo; Hoffmann, Andreas; Okanoya, Kazunori

    2012-06-01

    A method for analysis of a wide range of odor compounds in aqueous samples at sub-ng mL⁻¹ to μg mL⁻¹ levels was developed by full evaporation dynamic headspace (FEDHS) and gas chromatography-mass spectrometry (GC-MS). Compared to conventional DHS and headspace solid phase microextraction (HS-SPME), FEDHS provides more uniform enrichment over the entire polarity range for odor compounds in aqueous samples. FEDHS at 80°C using 3 L of purge gas allows complete vaporization of 100 μL of an aqueous sample, and trapping and drying it in an adsorbent packed tube, while providing high recoveries (85-103%) of the 18 model odor compounds (water solubility at 25°C: log0.54-5.65 mg L⁻¹, vapor pressure at 25°C: 0.011-3.2 mm Hg) and leaving most of the low volatile matrix behind. The FEDHS-GC-MS method showed good linearity (r²>0.9909) and high sensitivity (limit of detection: 0.21-5.2 ng mL⁻¹) for the model compounds even with the scan mode in the conventional MS. The feasibility and benefit of the method was demonstrated with analyses of key odor compounds including hydrophilic and less volatile characteristics in beverages (whiskey and green tea). In a single malt whiskey sample, phenolic compounds including vanillin could be determined in the range of 0.92-5.1 μg mL⁻¹ (RSDfuraneol, indole, maltol, and pyrazine congeners) were determined in the range of 0.21-110 ng mL⁻¹ (RSD<10%, n=6). Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Analysis of Volatile Components of Cape Gooseberry (Physalis peruviana L. Grown in Turkey by HS-SPME and GC-MS

    Directory of Open Access Journals (Sweden)

    Murat Yilmaztekin

    2014-01-01

    Full Text Available Volatile components in cape gooseberry fruit at ripe stage were collected using headspace-solid phase microextraction, and analyzed by gas chromatography-mass spectrometry. Three solid phase microextraction fiber coatings (DVB/CAR/PDMS, CAR/PDMS, and PDMS/DVB were tested for evaluation of volatile compounds. DVB/CAR/PDMS fiber showed a strong extraction capacity for volatile compounds and produced the best result in case of total peak areas. A total of 133 volatile compounds were identified in fruit pulp; among them 1-hexanol (6.86%, eucalyptol (6.66%, ethyl butanoate (6.47%, ethyl octanoate (4.01%, ethyl decanoate (3.39%, 4-terpineol (3.27%, and 2-methyl-1-butanol (3.10% were the major components in the sample extracts.

  12. Analysis of volatile components of cape gooseberry (Physalis peruviana L.) grown in Turkey by HS-SPME and GC-MS.

    Science.gov (United States)

    Yilmaztekin, Murat

    2014-01-01

    Volatile components in cape gooseberry fruit at ripe stage were collected using headspace-solid phase microextraction, and analyzed by gas chromatography-mass spectrometry. Three solid phase microextraction fiber coatings (DVB/CAR/PDMS, CAR/PDMS, and PDMS/DVB) were tested for evaluation of volatile compounds. DVB/CAR/PDMS fiber showed a strong extraction capacity for volatile compounds and produced the best result in case of total peak areas. A total of 133 volatile compounds were identified in fruit pulp; among them 1-hexanol (6.86%), eucalyptol (6.66%), ethyl butanoate (6.47%), ethyl octanoate (4.01%), ethyl decanoate (3.39%), 4-terpineol (3.27%), and 2-methyl-1-butanol (3.10%) were the major components in the sample extracts.

  13. Headspace versus direct immersion solid phase microextraction in complex matrixes: investigation of analyte behavior in multicomponent mixtures.

    Science.gov (United States)

    Gionfriddo, Emanuela; Souza-Silva, Érica A; Pawliszyn, Janusz

    2015-08-18

    This work aims to investigate the behavior of analytes in complex mixtures and matrixes with the use of solid-phase microextraction (SPME). Various factors that influence analyte uptake such as coating chemistry, extraction mode, the physicochemical properties of analytes, and matrix complexity were considered. At first, an aqueous system containing analytes bearing different hydrophobicities, molecular weights, and chemical functionalities was investigated by using commercially available liquid and solid porous coatings. The differences in the mass transfer mechanisms resulted in a more pronounced occurrence of coating saturation in headspace mode. Contrariwise, direct immersion extraction minimizes the occurrence of artifacts related to coating saturation and provides enhanced extraction of polar compounds. In addition, matrix-compatible PDMS-modified solid coatings, characterized by a new morphology that avoids coating fouling, were compared to their nonmodified analogues. The obtained results indicate that PDMS-modified coatings reduce artifacts associated with coating saturation, even in headspace mode. This factor, coupled to their matrix compatibility, make the use of direct SPME very practical as a quantification approach and the best choice for metabolomics studies where wide coverage is intended. To further understand the influence on analyte uptake on a system where additional interactions occur due to matrix components, ex vivo and in vivo sampling conditions were simulated using a starch matrix model, with the aim of mimicking plant-derived materials. Our results corroborate the fact that matrix handling can affect analyte/matrix equilibria, with consequent release of high concentrations of previously bound hydrophobic compounds, potentially leading to coating saturation. Direct immersion SPME limited the occurrence of the artifacts, which confirms the suitability of SPME for in vivo applications. These findings shed light into the implementation of in

  14. NMR investigation of acrolein stability in hydroalcoholic solution as a foundation for the valid HS-SPME/GC–MS quantification of the unsaturated aldehyde in beverages

    International Nuclear Information System (INIS)

    Kächele, Martin; Monakhova, Yulia B.; Kuballa, Thomas; Lachenmeier, Dirk W.

    2014-01-01

    Highlights: • Acrolein in hydroalcoholic solution degrades to 1,3,3-propanetriol and 3-hydroxypropionaldehyde. • Hydroquinone (0.2%) at pH 3.0 stabilizes acrolein solutions. • Quantitative HS-SPME/GC–MS determination of acrolein in alcoholic beverages was developed (LOD 14 μg L −1 ). • 6 of 117 samples had acrolein levels above the WHO threshold (1500 μg L −1 ). - Abstract: Acrolein (propenal) is found in many foods and beverages and may pose a health hazard due to its cytotoxicity. Considerable knowledge gaps regarding human exposure to acrolein exist, and there is a lack of reliable analytical methods. Hydroalcoholic dilutions prepared for calibration purposes from pure acrolein show considerable degradation of the compound and nuclear magnetic resonance (NMR) spectroscopy showed that 1,3,3-propanetriol and 3-hydroxypropionaldehyde are formed. The degradation can be prevented by addition of hydroquinone as stabilizer to the calibration solutions, which then show linear concentration-response behaviour required for quantitative analysis. The stabilized calibration solutions were used for quantitative headspace solid-phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS) determination of acrolein in alcoholic beverages with a detection limit of 14 μg L −1 . Of 117 tested alcoholic beverages, 64 were tested positive with the highest incidence in grape marc spirits and whiskey (100%, mean 252 μg L −1 ), followed by fruit spirits (86%, mean 591 μg/L −1 ), tequila (86%, mean 404 μg L −1 ), Asian spirits (43%, mean 54 μg L −1 ) and wine (9%, mean 0.7 μg L −1 ). Acrolein could not be detected in beer, vodka, absinthe and bottled water. Six of the fruit and grape marc spirits had acrolein levels above the World Health Organization (WHO) provisional tolerable concentration of 1.5 mg L −1

  15. NMR investigation of acrolein stability in hydroalcoholic solution as a foundation for the valid HS-SPME/GC–MS quantification of the unsaturated aldehyde in beverages

    Energy Technology Data Exchange (ETDEWEB)

    Kächele, Martin [Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Weissenburger Strasse 3, D-76187 Karlsruhe (Germany); Hochschule Mannheim, Paul-Wittsack-Strasse 10, D-68163 Mannheim (Germany); Monakhova, Yulia B. [Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Weissenburger Strasse 3, D-76187 Karlsruhe (Germany); Bruker Biospin GmbH, Silbersteifen, 76287 Rheinstetten (Germany); Department of Chemistry, Saratov State University, Astrakhanskaya Street 83, 410012 Saratov (Russian Federation); Kuballa, Thomas [Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Weissenburger Strasse 3, D-76187 Karlsruhe (Germany); Lachenmeier, Dirk W., E-mail: lachenmeier@web.de [Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Weissenburger Strasse 3, D-76187 Karlsruhe (Germany); Ministry of Rural Affairs and Consumer Protection, Kernerplatz 10, 70182 Stuttgart (Germany)

    2014-04-01

    Highlights: • Acrolein in hydroalcoholic solution degrades to 1,3,3-propanetriol and 3-hydroxypropionaldehyde. • Hydroquinone (0.2%) at pH 3.0 stabilizes acrolein solutions. • Quantitative HS-SPME/GC–MS determination of acrolein in alcoholic beverages was developed (LOD 14 μg L⁻¹. • 6 of 117 samples had acrolein levels above the WHO threshold (1500 μg L⁻¹). Abstract: Acrolein (propenal) is found in many foods and beverages and may pose a health hazard due to its cytotoxicity. Considerable knowledge gaps regarding human exposure to acrolein exist, and there is a lack of reliable analytical methods. Hydroalcoholic dilutions prepared for calibration purposes from pure acrolein show considerable degradation of the compound and nuclear magnetic resonance (NMR) spectroscopy showed that 1,3,3-propanetriol and 3-hydroxypropionaldehyde are formed. The degradation can be prevented by addition of hydroquinone as stabilizer to the calibration solutions, which then show linear concentration-response behaviour required for quantitative analysis. The stabilized calibration solutions were used for quantitative headspace solid-phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS) determination of acrolein in alcoholic beverages with a detection limit of 14 μg L⁻¹. Of 117 tested alcoholic beverages, 64 were tested positive with the highest incidence in grape marc spirits and whiskey (100%, mean 252 μg L⁻¹), followed by fruit spirits (86%, mean 591 μg/L⁻¹), tequila (86%, mean 404 μg L⁻¹), Asian spirits (43%, mean 54 μg L⁻¹) and wine (9%, mean 0.7 μg L⁻¹). Acrolein could not be detected in beer, vodka, absinthe and bottled water. Six of the fruit and grape marc spirits had acrolein levels above the World Health Organization (WHO) provisional tolerable concentration of 1.5 mg L⁻¹.

  16. Chemical composition analysis of the essential oil of Solanumn nigrum L. by HS/SPME method and calculation of the biochemical coefficients of the components

    Directory of Open Access Journals (Sweden)

    Avat (Arman Taherpour

    2017-05-01

    Full Text Available The volatile constituents of the essential oil of wild Solanumn nigrum L. obtained from the Kurdistan of Iraq were extracted by head-space/solid-phase micro-extraction (HS/SPME and were analyzed by gas chromatography (GC and gas chromatography/mass spectrometry (GC/MS. Of a total of twenty compounds in the oil, all of them were identified. The main components were as follows: Dillapiole (22.22%, α-Cadinol (16.47%, para-Cymene (10.01%, (E-1-(2,6,6-Trimethyl-1,3-cyclohexadien-1-yl-2-buten-1-one or β-damascenone (9.08%, α-Phellandrene (8.48%, β-Pinene (5.93%, α-Bisabolol acetate (4.53%, (Z,E-4,6,8-Megastigmatriene (4.09%, Phytol (2.49%, Linalyl butanoate (2.13%, 8-methylene-tricyclo[3.2.1.0(2,4]octane (2.60% and Limonene (2.03%. Some physicochemical properties, such as the logarithm of calculated octanol–water partitioning coefficients (logKow and total biodegradation (TBd in mol/h were calculated for compounds 1–20 from S. nigrum L.

  17. Possibilities and limitations of dynamic headspace sampling as a pre-concentration technique for trace analysis of organics by capillary gas chromatography

    NARCIS (Netherlands)

    Curvers, J.M.P.M.; Noij, T.H.M.; Cramers, C.A.M.G.; Rijks, J.A.

    1984-01-01

    The possibilities, the limitations and the quantitative performance of dynamic headspace sampling, in particular closed-loop stripping, were investigated for various classes of organic substances in aqueous samples with concentrations down to the parts per 1012 (ppt) level. The effects of variations

  18. Determination of 2-Propenal Using Headspace Solid-Phase Microextraction Coupled to Gas Chromatography–Time-of-Flight Mass Spectrometry as a Marker for Authentication of Unrefined Sesame Oil

    Directory of Open Access Journals (Sweden)

    Ahmad Rois Mansur

    2017-01-01

    Full Text Available Ascertaining the authenticity of the unrefined sesame oil presents an ongoing challenge. Here, the determination of 2-propenal was performed by headspace solid-phase microextraction (HS-SPME under mild temperature coupled to gas chromatography with time-of-flight mass spectrometry, enabling the detection of adulteration of unrefined sesame oil with refined corn or soybean oil. Employing this coupled technique, 2-propenal was detected in all tested refined corn and soybean oils but not in any of the tested unrefined sesame oil samples. Using response surface methodology, the optimum extraction temperature, equilibrium time, and extraction time for the HS-SPME analysis of 2-propenal using carboxen/polydimethylsiloxane fiber were determined to be 55°C, 15 min, and 15 min, respectively, for refined corn oil and 55°C, 25 min, and 15 min, respectively, for refined soybean oil. Under these optimized conditions, the adulteration of unrefined sesame oil with refined corn or soybean oils (1–5% was successfully detected. The detection and quantification limits of 2-propenal were found to be in the range of 0.008–0.010 and 0.023–0.031 µg mL−1, respectively. The overall results demonstrate the potential of this novel method for the authentication of unrefined sesame oil.

  19. Modified application of HS-SPME for quality evaluation of essential oil plant materials.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Szewczyk, Joanna; Dybowski, Michal P

    2016-01-01

    The main limitation in the standard application of head space analysis employing solid phase microextraction (HS-SPME) for the evaluation of plants as sources of essential oils (EOs) are different quantitative relations of EO components from those obtained by direct analysis of EO which was got in the steam distillation (SD) process from the same plant (EO/SD). The results presented in the paper for thyme, mint, sage, basil, savory, and marjoram prove that the quantitative relations of EO components established by HS-SPME procedure and direct analysis of EO/SD are similar when the plant material in the HS-SPME process is replaced by its suspension in oil of the same physicochemical character as that of SPME fiber coating. The observed differences in the thyme EO composition estimated by both procedures are insignificant (F(exp)analysis involving the SD procedure, the application of the new HS-SPME procedure proposed in this paper substantially shortens the evaluation time of plant material quality and thus may improve the efficiency of analytical laboratories. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Rapid analysis of Fructus forsythiae essential oil by ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction followed by gas chromatography–mass spectrometry

    International Nuclear Information System (INIS)

    Jiao, Jiao; Ma, Dan-Hui; Gai, Qing-Yan; Wang, Wei; Luo, Meng; Fu, Yu-Jie; Ma, Wei

    2013-01-01

    Graphical abstract: -- Highlights: •A new ILAMD-HS-SDME method is developed for the microextraction of essential oil. •ILs used as destruction agent of plant cell walls and microwave absorption medium. •Parameters affecting the extraction efficiency are optimized by Box–Behnken design. •Procedure benefits: similar constituents, shorter duration and smaller sample amount. •ILAMD-HS-SDME followed by GC–MS is a promising technique in analytical fields. -- Abstract: A rapid, green and effective miniaturized sample preparation and analytical technique, i.e. ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction (ILAMD-HS-SDME) followed by gas chromatography–mass spectrometry (GC–MS) was developed for the analysis of essential oil (EO) in Fructus forsythiae. In this work, ionic liquids (ILs) were not only used as the absorption medium of microwave irradiation but also as the destruction agent of plant cell walls. 1-Ethyl-3-methylimidazolium acetate ([C 2 mim]OAc) was chosen as the optimal ILs. Moreover, n-heptadecane (2.0 μL) was selected as the appropriate suspended solvent for the extraction and concentration of EO. Extraction conditions of the proposed method were optimized using the relative peak area of EO constituents as the index, and the optimal operational parameters were obtained as follows: irradiation power (300 W), sample mass (0.7 g), mass ratio of ILs to sample (2.4), temperature (78 °C) and time (3.4 min). In comparison to previous reports, the proposed method was faster and required smaller sample amount but could equally monitor all EO constituents with no significant differences

  1. Rapid analysis of Fructus forsythiae essential oil by ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction followed by gas chromatography–mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Jiao [State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040 (China); Ma, Dan-Hui [College of Life Sciences, Northeast Forestry University, Harbin 150040 (China); Gai, Qing-Yan; Wang, Wei; Luo, Meng [State Engineering Laboratory of Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040 (China); Fu, Yu-Jie, E-mail: yujie_fu2002@yahoo.com [State Engineering Laboratory of Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040 (China); Ma, Wei, E-mail: mawei@hljucm.net [State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040 (China); School of Pharmaceutical, Heilongjiang University of Chinese Medicine, Harbin 150040 (China)

    2013-12-04

    Graphical abstract: -- Highlights: •A new ILAMD-HS-SDME method is developed for the microextraction of essential oil. •ILs used as destruction agent of plant cell walls and microwave absorption medium. •Parameters affecting the extraction efficiency are optimized by Box–Behnken design. •Procedure benefits: similar constituents, shorter duration and smaller sample amount. •ILAMD-HS-SDME followed by GC–MS is a promising technique in analytical fields. -- Abstract: A rapid, green and effective miniaturized sample preparation and analytical technique, i.e. ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction (ILAMD-HS-SDME) followed by gas chromatography–mass spectrometry (GC–MS) was developed for the analysis of essential oil (EO) in Fructus forsythiae. In this work, ionic liquids (ILs) were not only used as the absorption medium of microwave irradiation but also as the destruction agent of plant cell walls. 1-Ethyl-3-methylimidazolium acetate ([C{sub 2}mim]OAc) was chosen as the optimal ILs. Moreover, n-heptadecane (2.0 μL) was selected as the appropriate suspended solvent for the extraction and concentration of EO. Extraction conditions of the proposed method were optimized using the relative peak area of EO constituents as the index, and the optimal operational parameters were obtained as follows: irradiation power (300 W), sample mass (0.7 g), mass ratio of ILs to sample (2.4), temperature (78 °C) and time (3.4 min). In comparison to previous reports, the proposed method was faster and required smaller sample amount but could equally monitor all EO constituents with no significant differences.

  2. Characterization of the major odor-active compounds in Thai durian ( Durio zibethinus L. 'Monthong') by aroma extract dilution analysis and headspace gas chromatography-olfactometry.

    Science.gov (United States)

    Li, Jia-Xiao; Schieberle, Peter; Steinhaus, Martin

    2012-11-14

    An aroma extract dilution analysis applied on the volatile fraction isolated from Thai durian by solvent extraction and solvent-assisted flavor evaporation resulted in 44 odor-active compounds in the flavor dilution (FD) factor range of 1-16384, 41 of which could be identified and 24 that had not been reported in durian before. High FD factors were found for ethyl (2S)-2-methylbutanoate (fruity; FD 16384), ethyl cinnamate (honey; FD 4096), and 1-(ethylsulfanyl)ethanethiol (roasted onion; FD 1024), followed by 1-(ethyldisulfanyl)-1-(ethylsulfanyl)ethane (sulfury, onion), 2(5)-ethyl-4-hydroxy-5(2)-methylfuran-3(2H)-one (caramel), 3-hydroxy-4,5-dimethylfuran-2(5H)-one (soup seasoning), ethyl 2-methylpropanoate (fruity), ethyl butanoate (fruity), 3-methylbut-2-ene-1-thiol (skunky), ethane-1,1-dithiol (sulfury, durian), 1-(methylsulfanyl)ethanethiol (roasted onion), 1-(ethylsulfanyl)propane-1-thiol (roasted onion), and 4-hydroxy-2,5-dimethylfuran-3(2H)-one (caramel). Among the highly volatile compounds screened by static headspace gas chromatography-olfactometry, hydrogen sulfide (rotten egg), acetaldehyde (fresh, fruity), methanethiol (rotten, cabbage), ethanethiol (rotten, onion), and propane-1-thiol (rotten, durian) were found as additional potent odor-active compounds. Fourteen of the 41 characterized durian odorants showed an alkane-1,1-dithiol, 1-(alkylsulfanyl)alkane-1-thiol, or 1,1-bis(alkylsulfanyl)alkane structure derived from acetaldehyde, propanal, hydrogen sulfide, and alkane-1-thiols. Among these, 1-(propylsulfanyl)ethanethiol, 1-{[1-(methylsulfanyl)ethyl]sulfanyl}ethanethiol, and 1-{[1-(ethylsulfanyl)ethyl]sulfanyl}ethanethiol were reported for the first time in a natural product.

  3. Aroma volatiles obtained at harvest by HS-SPME/GC-MS and INDEX/MS-E-nose fingerprint discriminate climacteric behaviour in melon fruit.

    Science.gov (United States)

    Chaparro-Torres, Libia A; Bueso, María C; Fernández-Trujillo, Juan P

    2016-05-01

    Melon aroma volatiles were extracted at harvest from juice of a climacteric near-isogenic line (NIL) SC3-5-1 with two quantitative trait loci (QTLs) introgressed which produced climacteric behaviour and its non-climacteric parental (PS) using two methodologies of analysis: static headspace solid phase micro-extraction (HS-SPME) by gas chromatography-mass spectrometry (GC-MS) and inside needle dynamic extraction (INDEX) by MS-based electronic nose (MS-E-nose). Of the 137 volatiles compounds identified, most were found at significantly higher concentrations in SC3-5-1 than in PS in both seasons. These volatiles were mostly esters, alcohols, sulfur-derived esters and even some aldehydes and others. The number of variables with high correlation values was reduced by using correlation network analysis. Partial least squares-discriminant analysis (PLS-DA) achieved the correct classification of PS and SC3-5-1. The ions m/z 74, 91, 104, 105, 106 and 108, mainly volatile derivatives precursor phenylalanine, were the most discriminant in SC3-5-1 and PS. As many as 104 QTLs were mapped in season 1 and at least 78 QTLs in each season with an effect above the PS mean. GC-MS gave better discrimination than E-nose. Most of the QTLs that mapped in both seasons enhanced aroma volatiles associated with climacteric behaviour. © 2015 Society of Chemical Industry.

  4. HS-SPME-GC-MS/MS Method for the Rapid and Sensitive Quantitation of 2-Acetyl-1-pyrroline in Single Rice Kernels.

    Science.gov (United States)

    Hopfer, Helene; Jodari, Farman; Negre-Zakharov, Florence; Wylie, Phillip L; Ebeler, Susan E

    2016-05-25

    Demand for aromatic rice varieties (e.g., Basmati) is increasing in the US. Aromatic varieties typically have elevated levels of the aroma compound 2-acetyl-1-pyrroline (2AP). Due to its very low aroma threshold, analysis of 2AP provides a useful screening tool for rice breeders. Methods for 2AP analysis in rice should quantitate 2AP at or below sensory threshold level, avoid artifactual 2AP generation, and be able to analyze single rice kernels in cases where only small sample quantities are available (e.g., breeding trials). We combined headspace solid phase microextraction with gas chromatography tandem mass spectrometry (HS-SPME-GC-MS/MS) for analysis of 2AP, using an extraction temperature of 40 °C and a stable isotopologue as internal standard. 2AP calibrations were linear between the concentrations of 53 and 5380 pg/g, with detection limits below the sensory threshold of 2AP. Forty-eight aromatic and nonaromatic, milled rice samples from three harvest years were screened with the method for their 2AP content, and overall reproducibility, observed for all samples, ranged from 5% for experimental aromatic lines to 33% for nonaromatic lines.

  5. Characterization of volatile profile from ten different varieties of Chinese jujubes by HS-SPME/GC-MS coupled with E-nose.

    Science.gov (United States)

    Chen, Qinqin; Song, Jianxin; Bi, Jinfeng; Meng, Xianjun; Wu, Xinye

    2018-03-01

    Volatile profile of ten different varieties of fresh jujubes was characterized by HS-SPME/GC-MS (headspace solid phase micro-extraction combined with gas chromatography-mass spectrometry) and E-nose (electronic nose). GC-MS results showed that a total of 51 aroma compounds were identified in jujubes, hexanoic acid, hexanal, (E)-2-hexenal, (Z)-2-heptenal, benzaldehyde and (E)-2-nonenal were the main aroma components with contributions that over 70%. Differentiation of jujube varieties was conducted by cluster analysis of GC-MS data and principal component analysis & linear discriminant analysis of E-nose data. Both results showed that jujubes could be mainly divided into two groups: group A (JZ, PDDZ, JSXZ and LWZZ) and group B (BZ, YZ, MZ, XZ and DZ). There were significant differences in contents of alcohols, acids and aromatic compounds between group A and B. GC-MS coupled with E-nose could be a fast and accurate method to identify the general flavor difference in different varieties of jujubes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Determination of multi-class herbicides in soil by liquid-solid extraction coupled with headspace solid phase microextraction method

    Directory of Open Access Journals (Sweden)

    Đurović-Pejčev Rada

    2016-01-01

    Full Text Available A method is described for simultaneous determination of five herbicides (metribuzin, acetochlor, clomazone, oxyfluorfen and dimethenamid belonging to different pesticides groups in soil samples. Developed headspace solid phase microextraction method (HS-SPME in combination with liquid-solid sample preparation (LS was optimized and applied in the analysis of some agricultural samples. Optimization of microextraction conditions, such as temperature, extraction time and sodium chloride (NaCl content was perfor-med using 100 μm polydimethyl-siloxane (PDMS fiber. The extraction effi-ciencies of methanol, methanol:acetone=1:1 and methanol:acetone:hexane= =2:2:1 and the optimum number of extraction steps during the sample prepa-ration, were tested, as well. Gas chromatography-mass spectrometry (GC-MS was used for detection and quantification, obtaining relative standard deviation (RSD below 13%, and recovery values higher than 83% for multiple analyses of soil samples fortified at 30 μg kg-1 of each herbicide. Limits of detection (LOD were less than 1.2 μg kg-1 for all the studied herbicides. [Projekat Ministarstva nauke Republike Srbije, br. TR31043 i br. III43005

  7. Determination of roasted pistachio (Pistacia vera L.) key odorants by headspace solid-phase microextraction and gas chromatography-olfactometry.

    Science.gov (United States)

    Aceña, Laura; Vera, Luciano; Guasch, Josep; Busto, Olga; Mestres, Montserrat

    2011-03-23

    Key odorants in roasted pistachio nuts have been determined for the first time. Two different pistachio varieties (Fandooghi and Kerman) have been analyzed by means of headspace solid-phase microextraction (HS-SPME) and gas chromatography-olfactometry (GCO). The aroma extract dilution analyses (AEDA) applied have revealed 46 and 41 odor-active regions with a flavor dilution (FD) factor≥64 for the Fandooghi and the Kerman varieties, respectively, and 39 of them were related to precisely identified compounds. These included esters, pyrazines, aldehydes, acids, furans, and phenols. The results show that the Fandooghi variety presents, not only more odor-active regions but also higher FD factors than the Kerman variety that can lead to the conclusion that the first variety has a richer aromatic profile than the second one. The descriptive sensory analysis (DSA) showed that the roasted, chocolate/coffee, and nutty attributes were rated significantly higher in the Fandooghi variety, whereas the green attribute was significantly higher in the Kerman one.

  8. Volatile compound changes during shelf life of dried Boletus edulis: comparison between SPME-GC-MS and PTR-ToF-MS analysis.

    Science.gov (United States)

    Aprea, Eugenio; Romano, Andrea; Betta, Emanuela; Biasioli, Franco; Cappellin, Luca; Fanti, Marco; Gasperi, Flavia

    2015-01-01

    Drying process is commonly used to allow long time storage of valuable porcini mushrooms (Boletus edulis). Although considered a stable product dried porcini flavour changes during storage. Monitoring of volatile compounds during shelf life may help to understand the nature of the observed changes. In the present work two mass spectrometric techniques were used to monitor the evolution of volatile compounds during commercial shelf life of dried porcini. Solid phase microextraction (SPME) coupled to gas chromatography - mass spectrometry (GC-MS) allowed the identification of 66 volatile compounds, 36 of which reported for the first time, monitored during the commercial shelf life of dried porcini. Proton transfer reaction - time of flight - mass spectrometry (PTR-ToF-MS) , a direct injection mass spectrometric technique, was shown to be a fast and sensitive instrument for the general monitoring of volatile compound evolution during storage of dried porcini. Furthermore, PTR-ToF-MS grants access to compounds whose determination would otherwise require lengthy pre-concentration and/or derivatization steps such as ammonia and small volatile amines. The two techniques, both used for the first time to study dried porcini, provided detailed description of time evolution of volatile compounds during shelf life. Alcohols, aldehydes, ketones and monoterpenes diminish during the storage while carboxylic acids, pyrazines, lactones and amines increase. The storage temperature modifies the rate of the observed changes influencing the final quality of the dried porcini. We showed the advantages of both techniques, suggesting a strategy to be adopted to follow time evolution of volatile compounds in food products during shelf life, based on the identification of compounds by GC-MS and the rapid time monitoring by PTR-ToF-MS measurements in order to maximize the advantages of both techniques. Copyright © 2015 John Wiley & Sons, Ltd.

  9. [Determination of flavor compounds in foxtail millet wine by gas chromatography-mass spectrometry coupled with headspace solid phase microextraction].

    Science.gov (United States)

    Liu, Jingke; Zhang, Aixia; Li, Shaohui; Zhao, Wei; Zhang, Yuzong; Xing, Guosheng

    2017-11-08

    To comprehensively understand flavor compounds and aroma characteristics of foxtail millet wine, extraction conditions were optimized with 85 μm polyacrylate (PA), 100 μm polydimethylsiloxane (PDMS), 75 μm carboxen (CAR)/PDMS and 50/30 μm divinylbenzene (DVB)/CAR/PDMS fibers. The flavor compounds in foxtail millet wine were investigated by gas chromatography-mass spectrometry (GC-MS) coupled with headspace solid phase microextraction (HS-SPME), and the odor characteristics and intensity were analyzed by odor active values (OAVs). The samples of 8 mL were placed in headspace vials with 1.5 g NaCl, then the headspace vials were heated at 60℃ for 40 min. Using HS-SPME with different fibers, a total of 55 flavor compounds were identified from the samples, including alcohols, esters, benzene derivatives, hydrocarbons, acids, aldehydes, ketones, terpenes, phenols and heterocycle compounds. The main flavor compounds were alcohols compounds. According to their OAVs, phenylethyl alcohol, styrene, 1-methyl-naphthalene, 2-methyl-naphthalene, benzaldehyde, benzeneacetaldehyde and 2-methoxy-phenol were established to be odor-active compounds. Phenylethyl alcohol and benzeneacetaldehyde were the most prominent odor-active compounds. PA and PDMS fibers had good extraction effect for polar and nonpolar compounds, respectively. CAR/PDMS and DVB/CAR/PDMS provided a similar compounds profile for moderate polar compounds. This research comprehensively determined flavor compounds of foxtail millet wine, and provided theoretical basis for product development and quality control.

  10. Comparative analysis of different methods of extraction of present hydrocarbons in industrial residual waters

    International Nuclear Information System (INIS)

    Santa, Judith Rocio; Serrano, Martin; Stashenko, Elena

    2002-01-01

    A comparison among four extraction techniques such as: liquid - liquid (LLE) continuous and for lots, solid phase extraction (SPE), solid phase micro extraction (SPME) and static headspace (S-HS) was carried out. The main purpose of this research was to determine the highest recovery efficiencies and how reproducible the tests are while varying parameters such as time, extraction technique, type of solvents and others. Chromatographic parameters were optimized in order to carry out the analyses. Hydrocarbon's quantification of residual waters was achieved by using a high-resolution gas chromatography with a gas flame ionization detector (HRGC-FID). Validation of the method was carried out by analyzing real samples taken in different sampling places of the residual waters treatment plant of Ecopetrol - Barrancabermeja. The use of extraction methods that require big solvent quantities and long time for analysis are losing validity day by day. Techniques such as the HS-SPME and static HS are offered as alternatives for quantifying hydrocarbons. They show total lack of solvents, high sensibility, selectivity and the techniques are reproducible. Solid phase micro extraction (SPME) and static headspace (static HS) techniques were chosen as the extraction techniques to validate the method in real samples. Both techniques showed similar results for the determination of total hydrocarbons (in the gasoline range)

  11. TBA PRODUCTION BY ACID HYDROLYSIS OF MTBE DURING HEATED HEADSPACE ANALYSIS & EVALUATION OF A BASE AS A PRESERVATIVE

    Science.gov (United States)

    At room temperature (20°±3°C), purge and trap samplers provide poor sensitivity for analysis of the fuel oxygenates that are alcohols, such as tertiary butyl alcohol (TBA). Because alcohols are miscible or highly soluble in water, they are not efficiently transferred to a gas chr...

  12. Stable isotope dilution assay (SIDA) and HS-SPME-GCMS quantification of key aroma volatiles for fruit and sap of Australian mango cultivars.

    Science.gov (United States)

    San, Anh T; Joyce, Daryl C; Hofman, Peter J; Macnish, Andrew J; Webb, Richard I; Matovic, Nicolas J; Williams, Craig M; De Voss, James J; Wong, Siew H; Smyth, Heather E

    2017-04-15

    Reported herein is a high throughput method to quantify in a single analysis the key volatiles that contribute to the aroma of commercially significant mango cultivars grown in Australia. The method constitutes stable isotope dilution analysis (SIDA) in conjunction with headspace (HS) solid-phase microextraction (SPME) coupled with gas-chromatography mass spectrometry (GCMS). Deuterium labelled analogues of the target analytes were either purchased commercially or synthesised for use as internal standards. Seven volatiles, hexanal, 3-carene, α-terpinene, p-cymene, limonene, α-terpinolene and ethyl octanoate, were targeted. The resulting calibration functions had determination coefficients (R 2 ) ranging from 0.93775 to 0.99741. High recovery efficiencies for spiked mango samples were also achieved. The method was applied to identify the key aroma volatile compounds produced by 'Kensington Pride' and 'B74' mango fruit and by 'Honey Gold' mango sap. This method represents a marked improvement over current methods for detecting and measuring concentrations of mango fruit and sap volatiles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Non-destructive profiling of volatile organic compounds using HS-SPME/GC-MS and its application for the geographical discrimination of white rice.

    Science.gov (United States)

    Lim, Dong Kyu; Mo, Changyeun; Lee, Dong-Kyu; Long, Nguyen Phuoc; Lim, Jongguk; Kwon, Sung Won

    2018-01-01

    The authenticity determination of white rice is crucial to prevent deceptive origin labeling and dishonest trading. However, a non-destructive and comprehensive method for rapidly discriminating the geographical origins of white rice between countries is still lacking. In the current study, we developed a volatile organic compound based geographical discrimination method using headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME/GC-MS) to discriminate rice samples from Korea and China. A partial least squares discriminant analysis (PLS-DA) model exhibited a good classification of white rice between Korea and China (accuracy = 0.958, goodness of fit = 0.937, goodness of prediction = 0.831, and permutation test p-value = 0.043). Combining the PLS-DA based feature selection with the differentially expressed features from the unpaired t-test and significance analysis of microarrays, 12 discriminatory biomarkers were found. Among them, hexanal and 1-hexanol have been previously known to be associated with the cultivation environment and storage conditions. Other hydrocarbon biomarkers are novel, and their impact on rice production and storage remains to be elucidated. In conclusion, our findings highlight the ability to rapidly discriminate white rice from Korea and China. The developed method maybe useful for the authenticity and quality control of white rice. Copyright © 2017. Published by Elsevier B.V.

  14. Non-destructive profiling of volatile organic compounds using HS-SPME/GC–MS and its application for the geographical discrimination of white rice

    Directory of Open Access Journals (Sweden)

    Dong Kyu Lim

    2018-01-01

    Full Text Available The authenticity determination of white rice is crucial to prevent deceptive origin labeling and dishonest trading. However, a non-destructive and comprehensive method for rapidly discriminating the geographical origins of white rice between countries is still lacking. In the current study, we developed a volatile organic compound based geographical discrimination method using headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS-SPME/GC–MS to discriminate rice samples from Korea and China. A partial least squares discriminant analysis (PLS-DA model exhibited a good classification of white rice between Korea and China (accuracy = 0.958, goodness of fit = 0.937, goodness of prediction = 0.831, and permutation test p-value = 0.043. Combining the PLS-DA based feature selection with the differentially expressed features from the unpaired t-test and significance analysis of microarrays, 12 discriminatory biomarkers were found. Among them, hexanal and 1-hexanol have been previously known to be associated with the cultivation environment and storage conditions. Other hydrocarbon biomarkers are novel, and their impact on rice production and storage remains to be elucidated. In conclusion, our findings highlight the ability to rapidly discriminate white rice from Korea and China. The developed method maybe useful for the authenticity and quality control of white rice.

  15. Glass bottle sampling solid phase microextraction gas chromatography mass spectrometry for breath analysis of drug metabolites.

    Science.gov (United States)

    Lu, Yan; Niu, Wenqi; Zou, Xue; Shen, Chengyin; Xia, Lei; Huang, Chaoqun; Wang, Hongzhi; Jiang, Haihe; Chu, Yannan

    2017-05-05

    Breath analysis is a non-invasive approach which may be applied to disease diagnosis and pharmacokinetic study. In the case of offline analysis, the exhaled gas needs to be collected and the sampling bag is often used as the storage vessel. However, the sampling bag usually releases some extra compounds, which may interfere with the result of the breath test. In this study, a novel breath sampling glass bottle was developed with a syringe needle sampling port for solid phase microextraction (SPME). Such a glass bottle scarcely liberates compounds and can be used to collect exhaled gas for ensuing analysis by gas chromatography-mass spectrometry (GC-MS). The glass bottle sampling SPME-GC-MS analysis was carried out to investigate the breath metabolites of myrtol, a multicompound drug normally used in the treatment of bronchitis and sinusitis. Four compounds, α-pinene, 2,3-dehydro-1,8-cineole, d-limonene and 1,8-cineole were found in the exhaled breath of all eight volunteers who had taken the myrtol. While for other ten subjects who had not used the myrtol, these compounds were undetectable. In the SPME-GC-MS analysis of the headspace of myrtol, three compounds were detected including α-pinene, d-limonene and 1,8-cineole. Comparing the results of breath and headspace analysis, it indicates that 2,3-dehydro-1,8-cineole in the breath is the metabolite of 1,8-cineole. It is the first time that this metabolite was identified in human breath. The study demonstrates that the glass bottle sampling SPME-GC-MS method is applicable to exhaled gas analysis including breath metabolites investigation of drugs like myrtol. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Method for covering a spme fibre with carbon nanotubes and resulting spme fibre

    OpenAIRE

    Bertrán, Enric; Jover Comas, Eric; García Céspedes, Jordi; Bayona Termens, Josep María

    2010-01-01

    [EN] The invention relates to a method for covering solid phase microextraction (SPME) fibres with carbon nanotubes (CNT), comprising the following operations: (i) depositing a layer of a metal material on the SPME fibre; (ii) applying a heat treatment in order to form catalytic metal nanoparticles in a reducing atmosphere; and (iii) applying carbon using chemical deposition techniques, thereby forming CNT on top ofthe metal nanoparticles. The invention also relates to a fibre obtain...

  17. Thermodynamic functions of hydrogen bonding of amines in methanol derived from solution calorimetry data and headspace analysis

    International Nuclear Information System (INIS)

    Zaitseva, Ksenia V.; Varfolomeev, Mikhail A.; Solomonov, Boris N.

    2012-01-01

    Highlights: ► Solution enthalpies and activity coefficients of amines in methanol were measured. ► Thermodynamic functions of H-bonding of amines with methanol were determined. ► Specific interaction entropy of amines in methanol can be about zero or positive. ► Cooperativity of H-bonds in methanol media is smaller than in water solutions. ► A new view on analysis of specific interaction of solute with methanol is presented. - Abstract: Reactivity and equilibrium properties of organic molecules in self-associated liquids greatly depend on the hydrogen bonding with solvent. This work contains comprehensive thermodynamic analysis of hydrogen bonding of aliphatic and aromatic amines in self-associated solvent methanol. Enthalpies of solution at infinite dilution and limiting activity coefficients for the studied systems were measured experimentally. Enthalpies and Gibbs energies of hydrogen bonding of amines with neat methanol were determined. These values were found to be decreased compared with hydrogen bond energy in equimolar complexes “methanol–amine” determined in inert solvent or base media. A linear dependence between enthalpies and Gibbs energies of hydrogen bonding of amines with neat methanol was observed. It was firstly revealed that the entropy of specific interactions of amines with neat methanol can be about zero or positive. Disruption of solvent–solvent hydrogen bonds can be regarded as the most important step during dissolution of amine in methanol. It was found that the cooperative effect influences on the Gibbs energies of hydrogen bonding of amines in methanol, but in a lesser extent than in aqueous solutions. The new results show that the hydrogen bonding process in the self-associated solvents differs significantly from equimolar complexation in aprotic media.

  18. Thermodynamic functions of hydrogen bonding of amines in methanol derived from solution calorimetry data and headspace analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zaitseva, Ksenia V., E-mail: zaitseva.ksenia@gmail.com [Chemical Institute, Kazan (Volga Region) Federal University, Kremlevskaya 18, Kazan 420008 (Russian Federation); Varfolomeev, Mikhail A., E-mail: vma.ksu@gmail.com [Chemical Institute, Kazan (Volga Region) Federal University, Kremlevskaya 18, Kazan 420008 (Russian Federation); Solomonov, Boris N., E-mail: boris.solomonov@ksu.ru [Chemical Institute, Kazan (Volga Region) Federal University, Kremlevskaya 18, Kazan 420008 (Russian Federation)

    2012-05-10

    Highlights: Black-Right-Pointing-Pointer Solution enthalpies and activity coefficients of amines in methanol were measured. Black-Right-Pointing-Pointer Thermodynamic functions of H-bonding of amines with methanol were determined. Black-Right-Pointing-Pointer Specific interaction entropy of amines in methanol can be about zero or positive. Black-Right-Pointing-Pointer Cooperativity of H-bonds in methanol media is smaller than in water solutions. Black-Right-Pointing-Pointer A new view on analysis of specific interaction of solute with methanol is presented. - Abstract: Reactivity and equilibrium properties of organic molecules in self-associated liquids greatly depend on the hydrogen bonding with solvent. This work contains comprehensive thermodynamic analysis of hydrogen bonding of aliphatic and aromatic amines in self-associated solvent methanol. Enthalpies of solution at infinite dilution and limiting activity coefficients for the studied systems were measured experimentally. Enthalpies and Gibbs energies of hydrogen bonding of amines with neat methanol were determined. These values were found to be decreased compared with hydrogen bond energy in equimolar complexes 'methanol-amine' determined in inert solvent or base media. A linear dependence between enthalpies and Gibbs energies of hydrogen bonding of amines with neat methanol was observed. It was firstly revealed that the entropy of specific interactions of amines with neat methanol can be about zero or positive. Disruption of solvent-solvent hydrogen bonds can be regarded as the most important step during dissolution of amine in methanol. It was found that the cooperative effect influences on the Gibbs energies of hydrogen bonding of amines in methanol, but in a lesser extent than in aqueous solutions. The new results show that the hydrogen bonding process in the self-associated solvents differs significantly from equimolar complexation in aprotic media.

  19. Application of solid phase micro extraction (SPME) in profiling hydrocarbons in oil spill cases

    International Nuclear Information System (INIS)

    Zuraidah Abdullah Munir; Norashikin Saim; Nurul Huda Mamat Ghani

    2008-01-01

    In environmental forensic, it is extremely important to have a fast and reliable method in identifying sources of spilled oil and petroleum products. In this study, solid phase micro extraction (SPME) method coupled to gas chromatography-mass spectrometry was developed for the analysis of hydrocarbons in diesel and petroleum contaminated soil samples. Optimization of SPME parameters such as extraction time, extraction temperature and desorption time, was performed using 100-μm poly dimethylsiloxane (PDMS) fiber. These parameters were studied at three levels by means of a central composite experimental design and the optimum experimental conditions were determined using response surface method. The developed SPME method was applied to determine the profiles of hydrocarbons in several oil contaminated soil sample. The SPME method was also used to study the effects of weathering on the profiles of hydrocarbons in unleaded gasoline, diesel and kerosene contaminated soil samples. After several days, significant losses of the lighter hydrocarbons were observed compared to the heavier ones. From these data, SPME method can be used to differentiate possible candidate sources in oil spill cases. (author)

  20. Effect of hot air drying on volatile compounds of Flammulina velutipes detected by HS-SPME-GC-MS and electronic nose.

    Science.gov (United States)

    Yang, Wenjian; Yu, Jie; Pei, Fei; Mariga, Alfred Mugambi; Ma, Ning; Fang, Yong; Hu, Qiuhui

    2016-04-01

    Volatile compounds are important factors that affect the flavor quality of Flammulina velutipes, but the changes occurring during hot air drying is still unclear. To clarify the dynamic changes of flavor components during hot air drying, comprehensive flavor characterization and volatile compounds of F. velutipes were evaluated using electronic nose technology and headspace solid phase micro-extraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS), respectively. Results showed that volatile components in F. velutipes significantly changed during hot air drying according to the principal component analysis and radar fingerprint chart of electronic nose. Volatile compounds of fresh F. velutipes consisted mainly of ketones, aldehydes and alcohols, and 3-octanone was the dominant compound. Drying process could significantly decrease the relative content of ketones and promoted the generation of alcohols, acids, and esters, which became the main volatile compounds of dried F. velutipes. These may provide a theoretical basis for the formation mechanism of flavor substances in dried F. velutipes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. The GC/MS Analysis of Volatile Components Extracted by Different Methods from Exocarpium Citri Grandis

    Directory of Open Access Journals (Sweden)

    Zhisheng Xie

    2013-01-01

    Full Text Available Volatile components from Exocarpium Citri Grandis (ECG were, respectively, extracted by three methods, that is, steam distillation (SD, headspace solid-phase microextraction (HS-SPME, and solvent extraction (SE. A total of 81 compounds were identified by gas chromatography-mass spectrometry including 77 (SD, 56 (HS-SPME, and 48 (SE compounds, respectively. Despite of the extraction method, terpenes (39.98~57.81% were the main volatile components of ECG, mainly germacrene-D, limonene, 2,6,8,10,14-hexadecapentaene, 2,6,11,15-tetramethyl-, (E,E,E-, and trans-caryophyllene. Comparison was made among the three methods in terms of extraction profile and property. SD relatively gave an entire profile of volatile in ECG by long-time extraction; SE enabled the analysis of low volatility and high molecular weight compounds but lost some volatiles components; HS-SPME generated satisfactory extraction efficiency and gave similar results to those of SD at analytical level when consuming less sample amount, shorter extraction time, and simpler procedure. Although SD and SE were treated as traditionally preparative extractive techniques for volatiles in both small batches and large scale, HS-SPME coupled with GC/MS could be useful and appropriative for the rapid extraction and qualitative analysis of volatile components from medicinal plants at analytical level.

  2. Variation in Scent Compounds of Oil-Bearing Rose (Rosa damascena Mill. Produced by Headspace Solid Phase Microextraction, Hydrodistillation and Solvent Extraction

    Directory of Open Access Journals (Sweden)

    Sabri Erbaş

    2016-03-01

    Full Text Available In this research, rose oil and rose water were hydro-distilled from the fresh oil-bearing rose flowers (Rosa damascena Mill. using Clevenger-type apparatus. Rose concretes were extracted from the fresh rose flowers by using non-polar solvents, e.g. diethyl ether, petroleum ether, cyclo-hexane, chloroform and n-hexane, and subsequently by evaporation of the solvents under vacuum. Absolutes were produced from the concretes with ethyl alcohol extraction at -20°C, leaving behind the wax and other paraffinic substances. Scent compounds of all these products detected by gas chromatography (GC-FID/GC-MS were compared with the natural scent compounds of fresh rose flower detected by using headspace solid phase microextraction (HS-SPME with carboxen/polydimethylsiloxane (CAR/PDMS fiber. A total of 46 compounds analysis were identified by HS-SPME-GC-MS in the fresh flower, and a total of 15 compounds were identified by GC-MS in the hydrodistilled rose oil. While main compounds in rose oil were geraniol (35.4%, citronellol (31.6%, and nerol (15.3%, major compound in fresh rose flower, rose water and residue water was phenylethyl alcohol (43.2, 35.6 and 98.2%, respectively. While the highest concrete yield (0.7% was obtained from diethyl ether extraction, the highest absolute yield (70.9% was obtained from the n-hexane concrete. The diethyl ether concrete gave the highest productivity of absolute, as 249.7 kg of fresh rose flowers was needed to produce 1 kg of absolute.

  3. Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS

    Directory of Open Access Journals (Sweden)

    Liao Hsuan-Yu

    2016-01-01

    Full Text Available The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05. An empirical model, consisting of the molecular weight and the polarizability, was developed to appropriately predict the partition coefficients of organic compounds. The empirical model for estimating the PDMS-gas partition coefficient will contribute to the practical applications of the SPME technique.

  4. Determination of Methyl tert-Butyl Ether and tert-Butyl Alcohol in Water by Solid-Phase Microextraction/Head Space Analysis in Comparison to EPA Method 5030/8260B

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Keun-Chan; Stringfellow, William T.

    2003-10-02

    Methyl tert-butyl ether (MTBE) is now one of the most common groundwater contaminants in the United States. Groundwater contaminated with MTBE is also likely to be contaminated with tert-butyl alcohol (TBA), because TBA is a component of commercial grade MTBE, TBA can also be used as a fuel oxygenate, and TBA is a biodegradation product of MTBE. In California, MTBE is subject to reporting at concentrations greater than 3 {micro}g/L. TBA is classified as a ''contaminant of current interest'' and has a drinking water action level of 12 {micro}g/L. In this paper, we describe the development and optimization of a simple, automated solid phase microextraction (SPME) method for the analysis of MTBE and TBA in water and demonstrate the applicability of this method for monitoring MTBE and TBA contamination in groundwater, drinking water, and surface water. In this method, the headspace (HS) of a water sample is extracted with a carboxen/polydimethylsiloxane SPME fiber, the MTBE and TBA are desorbed into a gas chromatograph (GC), and detected using mass spectrometry (MS). The method is optimized for the routine analysis of MTBE and TBA with a level of quantitation of 0.3 {micro}g/L and 4 {micro}g/L, respectively, in water. MTBE quantitation was linear for over two orders of concentration (0.3 {micro}g/L -80 {micro}g/L). TBA was found to be linear within the range of 4 {micro}g/L-7,900 {micro}g/L. The lower level of detection for MTBE is 0.03 {micro}g/L using this method. This SPME method using headspace extraction was found to be advantageous over SPME methods requiring immersion of the fiber into the water samples, because it prolonged the life of the fiber by up to 400 sample analyses. This is the first time headspace extraction SPME has been shown to be applicable to the measurement of both MTBE and TBA at concentrations below regulatory action levels. This method was compared with the certified EPA Method 5030/8260B (purge-and-trap/GC/MS) using split

  5. Preparation and characterization of sodium dodecyl sulfate doped polypyrrole solid phase micro extraction fiber and its application to endocrine disruptor pesticide analysis

    OpenAIRE

    Korba, Korcan; Pelit, Levent; Okçu Pelit, Füsun; Özdokur, K. Volkan; Ertaş, Hasan; Eroğlu, Ahmet E.; Ertaş, Fatma Nil

    2013-01-01

    A robust in house solid-phase micro extraction (SPME) surface has been developed for the headspace (HS)-SPME determination of endocrine disruptor pesticides, namely, Chlorpyrifos, Penconazole, Procymidone, Bromopropylate and Lambda-Cyhalothrin in wine sample by using sodium dodecylsulfate doped polypyrrole SPME fiber. Pyrrole monomer was electrochemically polymerized on a stainless steel wire in laboratory conditions in virtue of diminishing the cost and enhancing the analyte retention on its...

  6. Sol-gel-based SPME fiber as a reliable sampling technique for studying biogenic volatile organic compounds released from Clostridium tetani.

    Science.gov (United States)

    Ghader, Masoud; Shokoufi, Nader; Es-Haghi, Ali; Kargosha, Kazem

    2017-11-01

    A novel and efficient headspace solid-phase microextraction (HS-SPME) method, followed by gas chromatography mass spectrometry (GC-MS), was developed to study volatile organic compounds (VOCs) emerging from microorganisms. Two homemade SPME fibers, a semi-polar poly (dimethylsiloxane) (PDMS) fiber, and a polar polyethylene glycol (PEG) fiber, along with two commercial fibers (PDMS and PDMS/DVB) were used to collect VOCs emerging from Clostridium tetani which was cultured in different media. The adsorbed VOCs were desorbed and identified, in vitro, using GC-MS. The adsorption efficiency was improved by optimizing the time duration of adsorption and desorption. About 50 components were identified by the proposed method. The main detected compounds appeared to be sulfur containing compounds such as butanethioic acid S-methyl ester, dimethyl trisulfide, and dimethyl tetrasulfide. These volatile sulfur containing compounds are derived from amino acids containing the sulfur element, which probably coexist in the mentioned bacterium or are added to the culture media. The developed HS-SPME-GC-MS method allowed the determination of the chemical fingerprint of Clostridium tetani volatile constituents, and thus provides a new, simple, and reliable tool for studying the growth of microorganisms. Graphical abstract Investigation of biogenic VOCs released from Clostridium tetani using SPME-GC-MS.

  7. In-situ methylation of strongly polar organic acids in natural waters supported by ion-pairing agents for headspace GC-MSD analysis

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, P.L.; Walther, W. [Dresden University of Technology, Institute for Groundwater Managemant, Dresden (Germany); Nestler, W. [Institute for Technology and Economics, Department of Civil Engineering and Architecture, Dresden (Germany)

    1998-06-01

    Strongly polar organic substances like halogenated acetic acids have been analyzed in surface water and groundwater in the catchment area of the upper Elbe river in Saxony since 1992. Coming directly from anthropogenic sources like industry, agriculture and indirectly by rainfall, their concentrations can increase up to 100 {mu}g/L in the aquatic environment of this catchment area. A new static headspace GC-MSD method without a manual pre-concentration step is presented to analyze the chlorinated acetic acids relevant to the Elbe river as their volatile methyl esters. Using an ion-pairing agent as modifier for the in-situ methylation of the analytes by dimethylsulfate, a minimal detection limit of 1 {mu}g/L can be achieved. Problems like the thermal degradation of chlorinated acetic acids to halogenated hydrocarbons and changing reaction yields during the headspace methylation, could be effectively reduced. The method has been successfully applied to monitoring bank infiltrate, surface water, groundwater and water works pumped raw water according to health provision principles. (orig.) With 3 figs., 2 tabs., 29 refs.

  8. Monitoring gas-phase CO2 in the headspace of champagne glasses through combined diode laser spectrometry and micro-gas chromatography analysis.

    Science.gov (United States)

    Moriaux, Anne-Laure; Vallon, Raphaël; Parvitte, Bertrand; Zeninari, Virginie; Liger-Belair, Gérard; Cilindre, Clara

    2018-10-30

    During Champagne or sparkling wine tasting, gas-phase CO 2 and volatile organic compounds invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Gas-phase CO 2 in excess can even cause a very unpleasant tingling sensation perturbing both ortho- and retronasal olfactory perception. Monitoring as accurately as possible the level of gas-phase CO 2 above glasses is therefore a challenge of importance aimed at better understanding the close relationship between the release of CO 2 and a collection of various tasting parameters. Here, the concentration of CO 2 found in the headspace of champagne glasses served under multivariate conditions was accurately monitored, all along the 10 min following pouring, through a new combined approach by a CO 2 -Diode Laser Sensor and micro-gas chromatography. Our results show the strong impact of various tasting conditions (volume dispensed, intensity of effervescence, and glass shape) on the release of gas-phase CO 2 above the champagne surface. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Optimization of Solid Phase Micro-Extraction (SPME for Monitoring Occupational Exposure to Ethyl Benzene

    Directory of Open Access Journals (Sweden)

    H Heidari

    2012-05-01

    Full Text Available

    Background and Objectives: Analytical methods for volatile organic compounds (VOCs in different samples need extraction of compounds, by applying hazardous solvents. Solid phase micro-extraction (SPME is a solvent-free equilibrium extraction method, in which proper calibration can allow quantitative determinations of VOCs at a very good sensitivity without the use of any organic solvent. VOCs are generally present in urine only at trace levels, therefore, a sensitive procedure is needed for their trace determinations. Throughout this study, headspace solid phase micro-extraction (HS-SPME was followed by GC-FID for ethyl benzene in spiked urine was optimized.

    Methods: In this study, the parameters influencing SPME and gas chromatography of ethyl benzene, including extraction time, temperature, desorption temperature, desorption time, salt addition, sample pH, sample volume and sample agitation were investigated.

    Results: Extraction procedure was performed at 30°C for 6 min, using 0.2 gml-1 of NaCl in the sample solution. The sample volume and sample pH were optimized at 5 ml and 7 (neutral pH, respectively. Desorption of the ethyl benzene was carried out for 60 sec. at 250°C. The method was also validated with three different spiked urine samples and illustrated an appropriate reproducibility over six consecutive days as well as six within-day experiments. During this investigation, parameters of accuracy, linearity, and detection limits of the procedure were also evaluated.

    Conclusion: The developed method of HS- SPME-GC-FID proved to be a simple, convenient, and practical procedure, and was successfully used for measuring of ethyl benzene in spiked urine.

  10. Development of a HS-SPME-GC/MS protocol assisted by chemometric tools to study herbivore-induced volatiles in Myrcia splendens.

    Science.gov (United States)

    Souza Silva, Érica A; Saboia, Giovanni; Jorge, Nina C; Hoffmann, Camila; Dos Santos Isaias, Rosy Mary; Soares, Geraldo L G; Zini, Claudia A

    2017-12-01

    A headspace solid phase microextraction (HS-SPME) method combined with gas chromatography-mass spectrometry (GC/MS) was developed and optimized for extraction and analysis of volatile organic compounds (VOC) of leaves and galls of Myrcia splendens. Through a process of optimization of main factors affecting HS-SPME efficiency, the coating divivnilbenzene-carboxen-polydimethylsiloxane (DVB/Car/PDMS) was chosen as the optimum extraction phase, not only in terms of extraction efficiency, but also for its broader analyte coverage. Optimum extraction temperature was 30°C, while an extraction time of 15min provided the best compromise between extraction efficiencies of lower and higher molecular weight compounds. The optimized protocol was demonstrated to be capable of sampling plant material with high reproducibility, considering that most classes of analytes met the 20% RSD FDA criterion. The optimized method was employed for the analysis of three classes of M. splendens samples, generating a final list of 65 tentatively identified VOC, including alcohols, aldehydes, esters, ketones, phenol derivatives, as well as mono and sesquiterpenes. Significant differences were evident amongst the volatile profiles obtained from non-galled leaves (NGL) and leaf-folding galls (LFG) of M. splendens. Several differences pertaining to amounts of alcohols and aldehydes were detected between samples, particularly regarding quantities of green leaf volatiles (GLV). Alcohols represented about 14% of compounds detected in gall samples, whereas in non-galled samples, alcohol content was below 5%. Phenolic derived compounds were virtually absent in reference samples, while in non-galled leaves and galls their content ranged around 0.2% and 0.4%, respectively. Likewise, methyl salicylate, a well-known signal of plant distress, amounted for 1.2% of the sample content of galls, whereas it was only present in trace levels in reference samples. Chemometric analysis based on Heatmap associated

  11. Application of novel activated carbon fiber solid-phase, microextraction to the analysis of chlorinated hydrocarbons in water by gas chromatography-mass spectrometry

    International Nuclear Information System (INIS)

    Sun Tonghua; Jia Jinping; Fang Nenghu; Wang Yalin

    2005-01-01

    This paper presents a study on the performance of activated carbon fiber (ACF) used as extraction fiber for solid-phase microextraction (SPME) and its application for analysis of chlorinated hydrocarbons in water. By means of evaluating scanning electron microscope (SEM) images, specific surface area, pore volume, pore distribution, and properties of adsorption and desorption, the optimal active concentration of phosphoric acid has been determined. Coupled with gas chromatograph-mass spectrometry (GC-MS), ACF-SPME is suitable for determination chlorinated hydrocarbons in water with headspace. Experimental parameters such as adsorption and desorption conditions were studied. The optimized method has an acceptable linearity, good precision, with R.S.D. values <10% for each compound. Compared with commercial fibers, ACF has many advantages such as better resistance to organic solvents, better endurance to high temperature and longer lifetime

  12. Determination of N,N-dimethyltryptamine in beverages consumed in religious practices by headspace solid-phase microextraction followed by gas chromatography ion trap mass spectrometry.

    Science.gov (United States)

    Gaujac, Alain; Dempster, Nicola; Navickiene, Sandro; Brandt, Simon D; de Andrade, Jailson Bittencourt

    2013-03-15

    A novel analytical approach combining solid-phase microextraction (SPME)/gas chromatography ion trap mass spectrometry (GC-IT-MS) was developed for the detection and quantification N,N-dimethyltryptamine (DMT), a powerful psychoactive indole alkaloid present in a variety of South American indigenous beverages, such as ayahuasca and vinho da jurema. These particular plant products, often used within a religious context, are increasingly consumed throughout the world following an expansion of religious groups and the availability of plant material over the Internet and high street shops. The method described in the present study included the use of SPME in headspace mode combined GC-IT-MS and included the optimization of the SPME procedure using multivariate techniques. The method was performed with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber in headspace mode (70 min at 60 °C) which resulted in good precision (RSDvinho da jurema samples, obtained from Brazilian religious groups, which revealed DMT concentration levels between 0.10 and 1.81 g L(-1). Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Gas flow headspace liquid phase microextraction.

    Science.gov (United States)

    Yang, Cui; Qiu, Jinxue; Ren, Chunyan; Piao, Xiangfan; Li, Xifeng; Wu, Xue; Li, Donghao

    2009-11-06

    There is a trend towards the use of enrichment techniques such as microextraction in the analysis of trace chemicals. Based on the theory of ideal gases, theory of gas chromatography and the original headspace liquid phase microextraction (HS-LPME) technique, a simple gas flow headspace liquid phase microextraction (GF-HS-LPME) technique has been developed, where the extracting gas phase volume is increased using a gas flow. The system is an open system, where an inert gas containing the target compounds flows continuously through a special gas outlet channel (D=1.8mm), and the target compounds are trapped on a solvent microdrop (2.4 microL) hanging on the microsyringe tip, as a result, a high enrichment factor is obtained. The parameters affecting the enrichment factor, such as the gas flow rate, the position of the microdrop, the diameter of the gas outlet channel, the temperatures of the extracting solvent and of the sample, and the extraction time, were systematically optimized for four types of polycyclic aromatic hydrocarbons. The results were compared with results obtained from HS-LPME. Under the optimized conditions (where the extraction time and the volume of the extracting sample vial were fixed at 20min and 10mL, respectively), detection limits (S/N=3) were approximately a factor of 4 lower than those for the original HS-LPME technique. The method was validated by comparison of the GF-HS-LPME and HS-LPME techniques using data for PAHs from environmental sediment samples.

  14. Characterization of the Key Aroma Compounds in Proso Millet Wine Using Headspace Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Jingke Liu

    2018-02-01

    Full Text Available The volatile compounds in proso millet wine were extracted by headspace solid-phase microextraction (85 μm polyacrylate (PA, 100 μm polydimethylsiloxane (PDMS, 75 μm Carboxen (CAR/PDMS, and 50/30 μm divinylbenzene (DVB/CAR/PDMS fibers, and analyzed using gas chromatography-mass spectrometry; the odor characteristics and intensities were analyzed by the odor activity value (OAV. Different sample preparation factors were used to optimize this method: sample amount, extraction time, extraction temperature, and content of NaCl. A total of 64 volatile compounds were identified from the wine sample, including 14 esters, seven alcohols, five aldehydes, five ketones, 12 benzene derivatives, 12 hydrocarbons, two terpenes, three phenols, two acids, and two heterocycles. Ethyl benzeneacetate, phenylethyl alcohol, and benzaldehyde were the main volatile compounds found in the samples. According to their OAVs, 14 volatile compounds were determined to be odor-active compounds (OAV > 1, and benzaldehyde, benzeneacetaldehyde, 1-methyl-naphthalene, 2-methyl-naphthalene, and biphenyl were the prominent odor-active compounds (OAV > 50, having a high OAV. Principal component analysis (PCA showed the difference of distribution of the 64 volatile compounds and 14 odor-active compounds with four solid-phase microextraction (SPME fibers.

  15. Tank 241-C-103 headspace flammability

    International Nuclear Information System (INIS)

    Huckaby, J.L.

    1994-01-01

    Information regarding flammable vapors, gases, and aerosols is presented for the purpose of resolving the tank 241-C-103 headspace flammability issue. Analyses of recent vapor and liquid samples, as well as visual inspections of the tank headspace, are discussed in the context of tank dynamics. This document is restricted to issues regarding the flammability of gases, vapors, and an aerosol that may exist in the headspace of tank 241-C-103. While discussing certain information about the organic liquid present in tank 241-C-103, this document addresses neither the potential for, nor consequences of, a pool fire involving this organic liquid; they will be discussed in a separate report

  16. Tank 241-C-103 headspace flammability

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L.

    1994-01-01

    Information regarding flammable vapors, gases, and aerosols is presented for the purpose of resolving the tank 241-C-103 headspace flammability issue. Analyses of recent vapor and liquid samples, as well as visual inspections of the tank headspace, are discussed in the context of tank dynamics. This document is restricted to issues regarding the flammability of gases, vapors, and an aerosol that may exist in the headspace of tank 241-C-103. While discussing certain information about the organic liquid present in tank 241-C-103, this document addresses neither the potential for, nor consequences of, a pool fire involving this organic liquid; they will be discussed in a separate report.

  17. Simultaneous analysis of organochlorine pesticides and polychlorinated biphenyls in air samples by using accelerated solvent extraction (ASE) and solid-phase micro-extraction (SPME) coupled to gas chromatography dual electron capture detection.

    Science.gov (United States)

    Mokbel, Haifaa; Al Dine, Enaam Jamal; Elmoll, Ahmad; Liaud, Céline; Millet, Maurice

    2016-04-01

    An analytical method associating accelerated solvent extraction (ASE) and solid-phase micro-extraction (SPME) in immersion mode combined with gas chromatography dual electrons capture detectors (SPME-GC-2ECD) has been developed and studied for the simultaneous determination of 19 organochlorine pesticides (OCPs) and 22 polychlorinated biphenyls (PCBs) in air samples (active and XAD-2 passive samplers). Samples were extracted with ASE with acetonitrile using the following conditions: temperature, 150 °C; pressure, 1500 psi; static, 15 min; cycles, 3; purge, 300 s; flush, 100 %. Extracts were reduced to 1 mL, and 500 μL of this extract, filled with deionised water, was subject to SPME extraction. Experimental results indicated that the proposed method attained the best extraction efficiency under the optimised conditions: extraction of PCB-OCP mixture using 100-μm PDMS fibre at 80 °C for 40 min with no addition of salt. The performance of the proposed ASE-SPME-GC-2ECD methodology with respect to linearity, limit of quantification and detection was evaluated by spiking of XAD-2 resin with target compounds. The regression coefficient (R (2)) of most compounds was found to be high of 0.99. limits of detection (LODs) are between 0.02 and 4.90 ng m(-3), and limits of quantification (LOQs) are between 0.05 and 9.12 ng m(-3) and between 0.2 and 49 ng/sampler and 0.52 and 91 ng/sampler, respectively, for XAD-2 passive samplers. Finally, a developed procedure was applied to determine selected PCBs and OCPs in the atmosphere.

  18. Rapid differentiation of Chinese hop varieties (Humulus lupulus) using volatile fingerprinting by HS-SPME-GC-MS combined with multivariate statistical analysis.

    Science.gov (United States)

    Liu, Zechang; Wang, Liping; Liu, Yumei

    2018-01-18

    Hops impart flavor to beer, with the volatile components characterizing the various hop varieties and qualities. Fingerprinting, especially flavor fingerprinting, is often used to identify 'flavor products' because inconsistencies in the description of flavor may lead to an incorrect definition of beer quality. Compared to flavor fingerprinting, volatile fingerprinting is simpler and easier. We performed volatile fingerprinting using head space-solid phase micro-extraction gas chromatography-mass spectrometry combined with similarity analysis and principal component analysis (PCA) for evaluating and distinguishing between three major Chinese hops. Eighty-four volatiles were identified, which were classified into seven categories. Volatile fingerprinting based on similarity analysis did not yield any obvious result. By contrast, hop varieties and qualities were identified using volatile fingerprinting based on PCA. The potential variables explained the variance in the three hop varieties. In addition, the dendrogram and principal component score plot described the differences and classifications of hops. Volatile fingerprinting plus multivariate statistical analysis can rapidly differentiate between the different varieties and qualities of the three major Chinese hops. Furthermore, this method can be used as a reference in other fields. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  19. A multiresidue method for the analysis of 90 pesticides, 16 PAHs, and 22 PCBs in honey using QuEChERS-SPME.

    Science.gov (United States)

    Al-Alam, Josephine; Fajloun, Ziad; Chbani, Asma; Millet, Maurice

    2017-08-01

    An optimized analytical method was developed for the simultaneous analysis of 90 pesticides, 16 polycyclic aromatic hydrocarbons, and 22 polychlorinated biphenyls. The method was based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction using acetonitrile followed by a dispersive solid-phase extraction cleanup using primary-secondary amine and octadecyl (C 18 ). The extract obtained was concentrated by evaporation and then reconstituted with acetonitrile to prepare it for chromatographic analysis by liquid chromatography-triple-quadrupole tandem mass spectrometry and gas chromatography-ion-trap tandem mass spectrometry, which was preceded by a preconcentration step using solid-phase microextraction with appropriate fibers. The combination of the two extraction steps ensured efficient extract cleanup. The use of the two analytical instruments allowed the analysis of a large number of pollutants with a high reliability rate. The method developed was validated for linearity, which was studied with use of matrix-matched calibration curves in the concentration range between 10 and 3000 ng g -1 . The correlation coefficient (R 2 ) obtained was higher than 0.98 for most of the target compounds, with a relative standard deviation lower than 20% for repeatability and reproducibility. The limits of detection and quantification were lower than 20 and 60 ng g -1 respectively for the compounds analyzed, and the recoveries were between 60% and 103% for most compounds. Finally, the method was tested for its efficiency on real samples by the analysis of three honey samples in which seven pesticides and nine polycyclic aromatic hydrocarbons were determined. Graphical Abstract ᅟ.

  20. Novel proton-type ionic liquid doped polyaniline for the headspace solid-phase microextraction of amines

    International Nuclear Information System (INIS)

    Ai, Youhong; Zhao, Faqiong; Zeng, Baizhao

    2015-01-01

    Graphical abstract: The novel proton-type ionic liquid (1-sulfobutyl-3-methylimidazolium hydrosulfate) doped polyaniline coating showed granular porous nanostructure and it had high self-EF values and extraction efficiency for amines. - Highlights: • A proton-type ionic liquid-doped polyaniline was fabricated by electrodeposition. • It showed porous granular nanostructure and had large specific surface. • It had high extraction capacity to aromatic amines. • A reasonable self-enrichment factor of SPME fiber has been proposed. - Abstract: A novel proton-type ionic liquid doped polyaniline (HIL-doped PANI) coating was presented, which was prepared on a stainless steel wire by electrodeposition in an aqueous solution containing aniline and 1-sulfobutyl-3-methylimidazolium hydrosulfate. The HIL-doped PANI coating showed granular nanostructure and had large specific surface. When it was applied to the headspace solid-phase microextraction of several amines (i.e., aniline, N-methylaniline, 3-methylaniline, 2-chloroaniline and 3-chloroaniline), it showed high extraction efficiency. The enrichment factors were 191.8–343.9 for different amines, much higher than those of common PANI and commercial polydimethylsiloxane/divinylbenzene coatings. Coupled with gas chromatographic analysis, the linear ranges were 0.097–100 μg/L with correlation coefficients above 0.9942, and the detection limits were 0.012–0.048 μg/L (S/N = 3) for different amines. The relative standard deviations (RSD) were smaller than 8.1% for five successive measurements with single fiber and the fiber-to-fiber RSDs were 8.6–13.8% (n = 5) for these amines. The proposed method was successfully applied to the extraction and determination of amines in organic waste water samples, and the recoveries were 78.3–112.8% for different analytes

  1. Novel proton-type ionic liquid doped polyaniline for the headspace solid-phase microextraction of amines

    Energy Technology Data Exchange (ETDEWEB)

    Ai, Youhong [Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules (Ministry of Education), College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Zhao, Faqiong [Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Zeng, Baizhao, E-mail: bzzeng@whu.edu.cn [Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China)

    2015-06-23

    Graphical abstract: The novel proton-type ionic liquid (1-sulfobutyl-3-methylimidazolium hydrosulfate) doped polyaniline coating showed granular porous nanostructure and it had high self-EF values and extraction efficiency for amines. - Highlights: • A proton-type ionic liquid-doped polyaniline was fabricated by electrodeposition. • It showed porous granular nanostructure and had large specific surface. • It had high extraction capacity to aromatic amines. • A reasonable self-enrichment factor of SPME fiber has been proposed. - Abstract: A novel proton-type ionic liquid doped polyaniline (HIL-doped PANI) coating was presented, which was prepared on a stainless steel wire by electrodeposition in an aqueous solution containing aniline and 1-sulfobutyl-3-methylimidazolium hydrosulfate. The HIL-doped PANI coating showed granular nanostructure and had large specific surface. When it was applied to the headspace solid-phase microextraction of several amines (i.e., aniline, N-methylaniline, 3-methylaniline, 2-chloroaniline and 3-chloroaniline), it showed high extraction efficiency. The enrichment factors were 191.8–343.9 for different amines, much higher than those of common PANI and commercial polydimethylsiloxane/divinylbenzene coatings. Coupled with gas chromatographic analysis, the linear ranges were 0.097–100 μg/L with correlation coefficients above 0.9942, and the detection limits were 0.012–0.048 μg/L (S/N = 3) for different amines. The relative standard deviations (RSD) were smaller than 8.1% for five successive measurements with single fiber and the fiber-to-fiber RSDs were 8.6–13.8% (n = 5) for these amines. The proposed method was successfully applied to the extraction and determination of amines in organic waste water samples, and the recoveries were 78.3–112.8% for different analytes.

  2. Analysis of neutral volatile aroma components in Tilsit cheese using a combination of dynamic headspace technique, capillary gas chromatography and mass spectrometry

    International Nuclear Information System (INIS)

    Dillinger, K.H.

    2000-03-01

    Tilsit cheese is made by the influence of lab ferment and starter cultures on milk. The ripening is done by repeated inoculation of the surface of the Tilsit cheese with yeasts and read smear cultures. This surface flora forms the typical aroma of the Tilsit cheese during the ripening process. The aim of the work was to receive general knowledge about the kind and amount of the neutral volatile aroma components of Tilsit cheese. Beyond this the ability of forming aroma components by read smear cultures and the dispersion of these components in cheese was to be examined. The results were intended to evaluate the formation of aroma components in Tilsit cheese. The semi-quantitative analyses of the aroma components of all samples were done by combining dynamic headspace extraction, gas chromatography and mass spectrometry. In this process the neutral volatile aroma components were extracted by dynamic headspace technique, adsorbed on a trap, thermally desorbed, separated by gas chromatography, detected and identified by mass spectrometry. 63 components belonging to the chemical classes of esters, ketones, aldehydes, alcohols and sulfur containing substances as well as aromatic hydrocarbons, chlorinated hydrocarbons and hydrocarbons were found in the analysed cheese samples of different Austrian Tilsit manufacturing plants. All cheese samples showed a qualitative equal but quantitative varied spectrum of aroma components. The cultivation of pure cultures on a cheese agar medium showed all analysed aroma components to be involved in the biochemical metabolism of these cultures. The ability to produce aroma components greatly differed between the strains and it was not possible to correlate this ability with the taxonomic classification of the strains. The majority of the components had a non-homogeneous concentration profile in the cheese body. This was explained by effects of diffusion and temporal and spatial different forming of components by the metabolism of the

  3. Changes in SPME-extracted volatile compounds from Iberian ham during ripening

    Directory of Open Access Journals (Sweden)

    García, Carmen

    2009-07-01

    Full Text Available A headspace SPME procedure was tested to study the evolution of volatile compounds during the ripening of Iberian hams from pigs reared in a Montanera system (outdoorbased, with acorn and pasture available and a HO-Pienso system (indoor-based, with a high oleic acid concentrate. The effect of the ripening time on volatile compounds was more marked than the effect of feeding system. Most volatile compounds affected by the ripening time were compounds that come from Strecker and Maillard reactions, which increased significantly ( p Un procedimiento de microextración en fase sólida (SPME en espacio de cabeza fue ensayado para estudiar la evolución de los compuestos volátiles durante la curación de Jamones Ibéricos de cerdos criados en régimen de montanera (en libertad, con bellotas y pasto disponible y un sistema OH-Pienso (estabulados, con un pienso alto en ácido oléico. El efecto del tiempo de curación en los compuestos volátiles fue más marcado que el efecto de la alimentación. La mayoría de los compuestos volátiles afectados por el tiempo de curación fueron compuestos que proceden de la reacción de Strecker y Maillard, que se incrementaron significativamente (p p < 0.05. Algunos de ellos (ácido butanoico, 2,6- dimetilpiracina y 1-octen-3-ol fueron más abundantes en jamones de Montanera que en jamones de Pienso. Estas pequeñas diferencias podrían ser importantes porque los compuestos involucrados han sido identificados como aromas del jamón Ibérico.

  4. The application of headspace gas chromatography coupled to tandem quadrupole mass spectrometry for the analysis of furan in baby food samples.

    Science.gov (United States)

    Pugajeva, Iveta; Rozentale, Irina; Viksna, Arturs; Bartkiene, Elena; Bartkevics, Vadims

    2016-12-01

    Selective methodology employing a tandem quadrupole mass spectrometer coupled to a gas chromatograph with headspace autosampler (HS-GC-MS/MS) was elaborated in this study. Application of the elaborated procedure resulted in a limit of detection of 0.021μgkg(-1) and a limit of quantification of 0.071μgkg(-1). The mean recoveries during in-house validation ranged from 89% to 109%, and coefficients of variation for repeatability ranged from 4% to 11%. The proposed analytical method was applied for monitoring the furan content of 30 commercial baby food samples available on the Latvian retail market. The level of furan found in these samples varied from 0.45 to 81.9μgkg(-1), indicating that infants whose sole diet comprises baby food sold in jars and cans are exposed constantly to furan. Samples containing vegetables and meat had higher levels of furan than those containing only fruits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke

    Energy Technology Data Exchange (ETDEWEB)

    Conde, Francisco J.; Afonso, Ana M.; Gonzalez, Venerando; Ayala, Juan H. [University of La Laguna, Campus de Anchieta, Department of Analytical Chemistry, Nutrition and Food Science, La Laguna (Spain)

    2006-08-15

    A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make smoked foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L{sup -1}, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L{sup -1} and 2 L min{sup -1} for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-{mu}m carbowax-divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL{sup -1}. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity (R {sup 2}{>=}0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%). (orig.)

  6. Comparison of SPME Methods for Determining Volatile Compounds in Milk, Cheese, and Whey Powder

    Directory of Open Access Journals (Sweden)

    Michael H. Tunick

    2013-11-01

    Full Text Available Solid phase microextraction and gas chromatography-mass spectrometry (SPME-GC-MS are commonly used for qualitative and quantitative analysis of volatile compounds in various dairy products, but conditions have to be adjusted to maximize release while not generating new compounds that are absent in the original sample. Queso Fresco, a fresh non-melting cheese, may be heated at 60 °C for 30 min; in contrast, compounds are produced in milk when exposed to light and elevated temperatures, so milk samples are heated as little as possible. Products such as dehydrated whey protein are more stable and can be exposed to longer periods (60 min of warming at lower temperature (40 °C without decomposition, allowing for capture and analysis of many minor components. The techniques for determining the volatiles in dairy products by SPME and GC-MS have to be optimized to produce reliable results with minimal modifications and analysis times.

  7. Application of HS-SPME and GC-MS to characterization of volatile compounds emitted from Osmanthus flowers.

    Science.gov (United States)

    Deng, Chunhui; Song, Guoxin; Hu, Yaoming

    2004-12-01

    Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was developed for characterization of volatile compounds emitted from two varieties Osmanthus flowers of O. fragrans var. latifolius and O. fragrans var. thunbergii. The SPME parameters were studied, the optimum conditions of a 65 microm carbowax/divinylbenzene (CW/DVB), extraction temperature of 22 degrees C and extraction time of 10 min were obtained and applied to extraction of the volatile emissions. Fourteen compounds released from both varieties of Osmanthus flowers were separated and identified by GC-MS, which mainly included alpha-linalool, beta-linalool, trans-linalool oxide, cis-linalool oxide, alpha-lonone, beta-lonone, capraldehyde and decalactone. By comparing their peak areas, we found that the sums of the fourteen compounds from the two Osmanthus flowers were very close, while the relative contents of individual volatile compounds in the two emissions were very different. The relative content of alpha-linalool and beta-linalool in O. fragrans var. latifolius were 39.46% and 0.51%, while in O. fragrans var. thunbergii were 9.53% and 27.71%. Due to their different relative contents, the two varieties of flower have different fragrances.

  8. Quantification of transformation products of rocket fuel unsymmetrical dimethylhydrazine in soils using SPME and GC-MS.

    Science.gov (United States)

    Bakaikina, Nadezhda V; Kenessov, Bulat; Ul'yanovskii, Nikolay V; Kosyakov, Dmitry S

    2018-07-01

    Determination of transformation products (TPs) of rocket fuel unsymmetrical dimethylhydrazine (UDMH) in soil is highly important for environmental impact assessment of the launches of heavy space rockets from Kazakhstan, Russia, China and India. The method based on headspace solid-phase microextraction (HS SPME) and gas chromatography-mass spectrometry is advantageous over other known methods due to greater simplicity and cost efficiency. However, accurate quantification of these analytes using HS SPME is limited by the matrix effect. In this research, we proposed using internal standard and standard addition calibrations to achieve proper combination of accuracies of the quantification of key TPs of UDMH and cost efficiency. 1-Trideuteromethyl-1H-1,2,4-triazole (MTA-d3) was used as the internal standard. Internal standard calibration allowed controlling matrix effects during quantification of 1-methyl-1H-1,2,4-triazole (MTA), N,N-dimethylformamide (DMF), and N-nitrosodimethylamine (NDMA) in soils with humus content < 1%. Using SPME at 60 °C for 15 min by 65 µm Carboxen/polydimethylsiloxane fiber, recoveries of MTA, DMF and NDMA for sandy and loamy soil samples were 91-117, 85-123 and 64-132%, respectively. For improving the method accuracy and widening the range of analytes, standard addition and its combination with internal standard calibration were tested and compared on real soil samples. The combined calibration approach provided greatest accuracies for NDMA, DMF, N-methylformamide, formamide, 1H-pyrazole, 3-methyl-1H-pyrazole and 1H-pyrazole. For determination of 1-formyl-2,2-dimethylhydrazine, 3,5-dimethylpyrazole, 2-ethyl-1H-imidazole, 1H-imidazole, 1H-1,2,4-triazole, pyrazines and pyridines, standard addition calibration is more suitable. However, the proposed approach and collected data allow using both approaches simultaneously. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Why do Ladybugs Smell Bad? In-vivo Quantification of Odorous Insect Kairomones with SPME and Multidimensional GC-MS-Olfactometry

    International Nuclear Information System (INIS)

    Cai Lingshuang; Koziel, Jacek A.; O'Neal, Matthew E.

    2009-01-01

    Winemakers, small fruit growers, and homeowners are concerned with noxious compounds released by multicolored Asian ladybird beetles (Harmonia axyridis, Coleoptera: Coccinellidae). New method based on headspace solid phase microextraction (HS-SPME) coupled with multidimensional gas chromatography mass spectrometry--olfactometry (MDGC-MS-O) system was developed for extraction, isolation and simultaneous identification of compounds responsible for the characteristic odor of live H. axyridis. Four methoxypyrazines (MPs) were identified in headspace volatiles of live H. axyridis as those responsible for the characteristic odor: 2, 5-dimethy1-3-methoxypyrazine (DMMP), 2-isopropy1-3-methoxypyrazine (IPMP), 2-sec-buty1-3-methoxypyrazine (SBMP), and 2-isobuty1-3-methoxypyrazine (IBMP). To the best of our knowledge this is the first report of H. axyridis releasing DMMP and the first report of this compound being a component of the H. axyridis characteristic odor. Quantification of three MPs (IPMP, SBMP and IBMP) emitted from live H. axyridis were performed using external calibration with HS-SPME and direct injections. A linear relationship (R 2 >0.9958 for all 3 MPs) between MS response and concentration of standard was observed over a concentration range from 0.1 ng L -1 to 0.05 μg L -1 for HS-SPME-GC-MS. The method detection limits (MDL) based on multidimensional GC-MS approach for three MPs were estimated to be between 0.020 ng L -1 . to 0.022 ng L -1 . This methodology is applicable for in vivo determination of odor-causing chemicals associated with emissions of volatiles from insects.

  10. Characterization of volatile substances in apples from Rosaceae family by headspace solid-phase microextraction followed by GC-qMS.

    Science.gov (United States)

    Ferreira, Liseth; Perestrelo, Rosa; Caldeira, Michael; Câmara, José S

    2009-06-01

    The volatile composition of different apple varieties of Malus domestica Borkh. species from different geographic regions at Madeira Islands, namely Ponta do Pargo (PP), Porto Santo (PS), and Santo da Serra (SS) was established by headspace solid-phase microextraction (HS-SPME) procedure followed by GC-MS (GC-qMS) analysis. Significant parameters affecting sorption process such as fiber coating, extraction temperature, extraction time, sample amount, dilution factor, ionic strength, and desorption time, were optimized and discussed. The SPME fiber coated with 50/30 microm divinylbenzene/carboxen/PDMS (DVB/CAR/PDMS) afforded highest extraction efficiency of volatile compounds, providing the best sensitivity for the target volatiles, particularly when the samples were extracted at 50 degrees C for 30 min with constant magnetic stirring. A qualitative and semi-quantitative analysis between the investigated apple species has been established. It was possible to identify about 100 of volatile compounds among pulp (46, 45, and 39), peel (64, 60, and 64), and entire fruit (65, 43, and 50) in PP, PS, and SS apples, respectively. Ethyl esters, terpenes, and higher alcohols were found to be the most representative volatiles. Alpha-farnesene, hexan-1-ol and hexyl 2-methylbutyrate were the compounds found in the volatile profile of studied apples with the largest GC area, representing, on average, 24.71, 14.06, and 10.80% of the total volatile fraction from PP, PS, and SS apples. In PP entire apple, the most abundant compounds identified were alpha-farnesene (30.49%), the unknown compound m/z (69, 101, 157) (21.82%) and hexyl acetate (6.57%). Regarding PS entire apple the major compounds were alpha-farnesene (16.87%), estragole (15.43%), hexan-1-ol (10.94), and E-2-hexenal (10.67). Alpha-farnesene (30.3%), hexan-1-ol (18.90%), 2-methylbutanoic acid (4.7%), and pentan-1-ol (4.6%) were also found as SS entire apple volatiles present in a higher relative content. Principal

  11. Solid Phase Microextraction (SPME in Determination of Pesticide Residues in Soil Samples

    Directory of Open Access Journals (Sweden)

    Rada Đurović

    2011-01-01

    Full Text Available The basic principles and application possibilities of the methods based on solid phase microextraction (SPME in the analysis of pesticide residues in soil samples are presented in the paper. The most important experimental parameters which affect SPME efficacy inpesticide determination (type and thickness of microextraction fiber, duration of microextraction,temperature at which it is conducted, effect of addition of salts (the effect of efflorescence,temperature and time of desorption, the choice of optimal solvent for pesticide exctraction from the soil and the optimal number of extraction steps, as well as general guidelines for their optimization are also shown. In the end, current applications of SPMEmethods in the analysis of pesticide residues in soil samples are presented.

  12. Analysis of the essential oils from Calendula officinalis growing in Brazil using three different extraction procedures Análise por CG-EM do óleo essencial de Calendula officinalis cultivado no Brasil utilizando-se três diferentes processos de extração

    Directory of Open Access Journals (Sweden)

    Zilda Cristina Gazim

    2008-09-01

    Full Text Available Terpenes and aroma volatiles from flowers of Calendula officinalis cultivated in southeastern Brazil were obtained by steam distillation (SD, headspace-cold finger (HS-CF extraction and headspace solid-phase microextraction (HS-SPME coupled with gas chromatography and mass spectrometric analysis. The dried flowers contained 0.1% oil. Kovats indices and mass spectra were used to identify 27 individual components in the various volatile fractions. The main components present in the volatile fractions of the C. officinalis flowers, obtained by SD, HS-SPME, and HS-CF, were δ-cadinene (22.5, 22.1, and 18.4 % and γ-cadinene (8.9, 25.4, and 24.9 % while 20.4 % of α-cadinol was seen only after SD extraction.Terpenos e aromas voláteis das flores de Calendula officinalis cultivados no sudoeste do Brasil foram isolados por arraste a vapor (SD, dedo frio (HS-CF e micro extração em fase sólida (HS-SPME acoplada à espectrometria de massas. As flores secas da C. officinalis contêm 0,1% de óleo essencial e foram identificadas 27 substâncias químicas através do cálculo do índice de Kováts e interpretação dos espectros de massas. As substâncias majoritárias presentes no óleo essencial das flores de C. officinalis, obtido por SD, HS-SPME e HS-CF foram δ-cadinene (22,5; 22,1 e 18,4 % γ-cadinene (8,9, 25,4 e 24,9 % e 20.4 % de α-cadinol foi observado apenas na extração por arraste a vapor.

  13. Volatile Compound Profiling by HS-SPME/GC-MS-FID of a Core Olive Cultivar Collection as a Tool for Aroma Improvement of Virgin Olive Oil

    Directory of Open Access Journals (Sweden)

    Lourdes García-Vico

    2017-01-01

    Full Text Available Virgin olive oil (VOO is the only food product requiring official sensory analysis to be classified in commercial categories, in which the evaluation of the aroma plays a very important role. The selection of parents, with the aim of obtaining new cultivars with improved oil aroma, is of paramount importance in olive breeding programs. We have assessed the volatile fraction by headspace-solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (HS-SPME/GC-MS-FID and the deduced aroma properties of VOO from a core set of olive cultivars (Core-36 which possesses most of the genetic diversity found in the World Olive Germplasm Collection (IFAPA Alameda del Obispo located in Cordoba, Spain. The VOO volatile fractions of Core-36 cultivars display a high level of variability. It is mostly made of compounds produced from polyunsaturated fatty acids through the lipoxygenase pathway, which confirms to be a general characteristic of the olive species (Olea europaea L.. The main group of volatile compounds in the oils was six straight-chain carbon compounds derived from linolenic acid, some of them being the main contributors to the aroma of the olive oils according to their odor activity values (OAV. The high level of variability found for the volatile fraction of the oils from Core-36 and, therefore, for the aroma odor notes, suggest that this core set may be a very useful tool for the choice of optimal parents in olive breeding programs in order to raise new cultivars with improved VOO aroma.

  14. The study of fingerprint characteristics of Dayi Pu-Erh tea using a fully automatic HS-SPME/GC-MS and combined chemometrics method.

    Directory of Open Access Journals (Sweden)

    Shidong Lv

    Full Text Available The quality of tea is presently evaluated by the sensory assessment of professional tea tasters, however, this approach is both inconsistent and inaccurate. A more standardized and efficient method is urgently needed to objectively evaluate tea quality. In this study, the chemical fingerprint of 7 different Dayi Pu-erh tea brands and 3 different Ya'an tea brands on the market were analyzed using fully automatic headspace solid-phase microextraction (HS-SPME combined with gas chromatography-mass spectrometry (GC-MS. A total of 78 volatiles were separated, among 75 volatiles were identified by GC-MS in seven Dayi Pu-erh teas, and the major chemical components included methoxyphenolic compounds, hydrocarbons, and alcohol compounds, such as 1,2,3-trimethoxybenzene, 1,2,4-trimethoxybenzene, 2,6,10,14-tetramethyl-pentadecane, linalool and its oxides, α-terpineol, and phytol. The overlapping ratio of peaks (ORP of the chromatogram in the seven Dayi Pu-erh tea samples was greater than 89.55%, whereas the ORP of Ya'an tea samples was less than 79.10%. The similarity and differences of the Dayi Pu-erh tea samples were also characterized using correlation coefficient similarity and principal component analysis (PCA. The results showed that the correlation coefficient of similarity of the seven Dayi Pu-erh tea samples was greater than 0.820 and was gathered in a specific area, which showed that samples from different brands were basically the same, despite have some slightly differences of chemical indexes was found. These results showed that the GC-MS fingerprint combined with the PCA approach can be used as an effective tool for the quality assessment and control of Pu-erh tea.

  15. Volatile Compound Profiling by HS-SPME/GC-MS-FID of a Core Olive Cultivar Collection as a Tool for Aroma Improvement of Virgin Olive Oil.

    Science.gov (United States)

    García-Vico, Lourdes; Belaj, Angjelina; Sánchez-Ortiz, Araceli; Martínez-Rivas, José M; Pérez, Ana G; Sanz, Carlos

    2017-01-14

    Virgin olive oil (VOO) is the only food product requiring official sensory analysis to be classified in commercial categories, in which the evaluation of the aroma plays a very important role. The selection of parents, with the aim of obtaining new cultivars with improved oil aroma, is of paramount importance in olive breeding programs. We have assessed the volatile fraction by headspace-solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (HS-SPME/GC-MS-FID) and the deduced aroma properties of VOO from a core set of olive cultivars (Core-36) which possesses most of the genetic diversity found in the World Olive Germplasm Collection (IFAPA Alameda del Obispo) located in Cordoba, Spain. The VOO volatile fractions of Core-36 cultivars display a high level of variability. It is mostly made of compounds produced from polyunsaturated fatty acids through the lipoxygenase pathway, which confirms to be a general characteristic of the olive species ( Olea europaea L.). The main group of volatile compounds in the oils was six straight-chain carbon compounds derived from linolenic acid, some of them being the main contributors to the aroma of the olive oils according to their odor activity values (OAV). The high level of variability found for the volatile fraction of the oils from Core-36 and, therefore, for the aroma odor notes, suggest that this core set may be a very useful tool for the choice of optimal parents in olive breeding programs in order to raise new cultivars with improved VOO aroma.

  16. NMR investigation of acrolein stability in hydroalcoholic solution as a foundation for the valid HS-SPME/GC-MS quantification of the unsaturated aldehyde in beverages.

    Science.gov (United States)

    Kächele, Martin; Monakhova, Yulia B; Kuballa, Thomas; Lachenmeier, Dirk W

    2014-04-11

    Acrolein (propenal) is found in many foods and beverages and may pose a health hazard due to its cytotoxicity. Considerable knowledge gaps regarding human exposure to acrolein exist, and there is a lack of reliable analytical methods. Hydroalcoholic dilutions prepared for calibration purposes from pure acrolein show considerable degradation of the compound and nuclear magnetic resonance (NMR) spectroscopy showed that 1,3,3-propanetriol and 3-hydroxypropionaldehyde are formed. The degradation can be prevented by addition of hydroquinone as stabilizer to the calibration solutions, which then show linear concentration-response behaviour required for quantitative analysis. The stabilized calibration solutions were used for quantitative headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) determination of acrolein in alcoholic beverages with a detection limit of 14 μg L(-1). Of 117 tested alcoholic beverages, 64 were tested positive with the highest incidence in grape marc spirits and whiskey (100%, mean 252 μg L(-1)), followed by fruit spirits (86%, mean 591 μg/L(-1)), tequila (86%, mean 404 μg L(-1)), Asian spirits (43%, mean 54 μg L(-1)) and wine (9%, mean 0.7 μg L(-1)). Acrolein could not be detected in beer, vodka, absinthe and bottled water. Six of the fruit and grape marc spirits had acrolein levels above the World Health Organization (WHO) provisional tolerable concentration of 1.5 mg L(-1). Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS

    OpenAIRE

    Liao Hsuan-Yu; Huang Miao-Ling; Lu Yu-Ting; Chao Keh-Ping

    2016-01-01

    The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05). An empirical model, consisting of the molecular weight and the polarizability, was ...

  18. Analysis of enantiomeric and non-enantiomeric monoterpenes in plant emissions using portable dynamic air sampling/solid-phase microextraction (PDAS-SPME) and chiral gas chromatography/mass spectrometry

    Science.gov (United States)

    Yassaa, Noureddine; Williams, Jonathan

    A portable dynamic air sampler (PDAS) using a porous polymer solid-phase microextraction (SPME) fibre has been validated for the determination of biogenic enantiomeric and non-enantiomeric monoterpenes in air. These compounds were adsorbed in the field, and then thermally desorbed at 250 °C in a gas chromatograph injector port connected via a β-cyclodextrin capillary separating column to a mass spectrometer. The optimized method has been applied for investigating the emissions of enantiomeric monoterpenes from Pseudotsuga menziesii (Douglas-fir), Rosmarinus officinalis (Rosemary) and Lavandula lanata (Lavender) which were selected as representative of coniferous trees and aromatic plants, respectively. The enantiomers of α-pinene, sabinene, camphene, δ-3-carene, β-pinene, limonene, β-phellandrene, 4-carene and camphor were successfully determined in the emissions from the three plants. While Douglas-fir showed a strong predominance toward (-)-enantiomers, Rosemary and Lavender demonstrated a large variation in enantiomeric distribution of monoterpenes. The simplicity, rapidity and sensitivity of dynamic sampling with porous polymer coated SPME fibres coupled to chiral capillary gas chromatography/mass spectrometry (GC/MS) makes this method potentially useful for in-field investigations of atmosphere-biosphere interactions and studies of optically explicit atmospheric chemistry.

  19. A molybdenum disulfide/reduced graphene oxide fiber coating coupled with gas chromatography-mass spectrometry for the saponification-headspace solid-phase microextraction of polychlorinated biphenyls in food.

    Science.gov (United States)

    Lv, Fangying; Gan, Ning; Cao, Yuting; Zhou, You; Zuo, Rongjie; Dong, Youren

    2017-11-24

    In this work, the molybdenum disulfide/reduced graphene oxide (MoS 2 /RGO) composite material was synthesized as a fiber coating to extract seven indicator polychlorinated biphenyls (PCBs; PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, and PCB180) present in food via a saponification-headspace solid-phase microextraction assay (saponification-HS-SPME). The MoS 2 /RGO coating was prepared and deposited on a stainless steel wire with the help of a silicone sealant and used as an SPME fiber. The alkali solution dissolved the fat and helped in releasing the PCBs present in milk to the headspace for extraction under 100°C. Following desorption in the inlet, the targets were quantified by gas chromatography-mass spectrometry. The effects of sorbent dosage, extraction time, added salts, and stirring rate on the extraction efficiency were investigated. The new coating was able to adsorb a higher amount of analytes, which was about 1.1-2.9 times in comparison with the commercially available SPME fiber (coated with divinylbenzene/carboxen/polydimethylsiloxane). It also showed the highest adsorption capability toward PCBs, which was 1.5-2.7 times that of the prepared RGO modified fiber. Moreover, MoS 2 also showed a strong affinity toward PCBs in a manner similar to its affinity for graphene. The developed method is simple and environmentally friendly as it does not require any organic solvents. Furthermore, it exhibits good sensitivity with detection limits less than 0.1ngmL -1 , linearity (0.25-100ngmL -1 ), and reproducibility (relative standard deviation below 10% for n=3). The novel SPME fibers are inexpensive, reusable, and can be easily prepared and manipulated. In addition, the saponification-HS-SPME assay was also found to be suitable for screening persistent organic pollutants in dairy products. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Determination of Sesquiterpenes in Wines by HS-SPME Coupled with GC-MS

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    Fabrizio Cincotta

    2015-07-01

    Full Text Available The sesquiterpene compounds present in red wines were characterized and quantified by Headspace Solid-Phase Microextraction in combination with Gas Chromatography–Mass Spectrometry (HS-SPME-GC-MS. Sixteen sesquiterpenes were identified, mainly hydrocarbons but also derived oxygenated compounds. Sesquiterpenes were acyclic, monocyclic, byciclic and tryciclic. Sesquiterpenes were detected in SIM (selected ion monitoring mode using their characteristics ions. All the sesquiterpenes were identified by mass spectral data, linear retention indices (LRI, literature data and injection of standards where available. Quantitative results were obtained using the method of standard additions. The method showed an average LOD = 0.05 µg L−1 and LOQ = 0.15 µg L−1. The monocyclic sesquiterpene with the germacrene skeleton, Germacrene D and the bicyclic sesquiterpene with the muurolane skeleton, α-muurolene were present in all the wine samples analysed. Syrah wines were the samples richest in sesquiterpenes in agreement with their typical spicy and woody notes. The results evidenced the possibility to use sesquiterpenes for wine authenticity and traceability.

  1. Volatile emerging contaminants in melon fruits, analysed by HS-SPME-GC-MS.

    Science.gov (United States)

    Cincotta, Fabrizio; Verzera, Antonella; Tripodi, Gianluca; Condurso, Concetta

    2018-03-01

    The aim of this research was to develop and validate a headspace-solid phase micro-extraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method for the determination of volatile emerging contaminants in fruit. The method showed good precision (RSD ≤ 14%) and satisfactory recoveries (99.1-101.7%) and LOD and LOQ values ranging between 0.011-0.033 μg kg -1 and 0.037-0.098 μg kg -1 , respectively. The method was applied to investigate the content of volatile emerging contaminants in two varieties of melon fruit (Cucumis melo L.) cultivated adjoining high-risk areas. Glycol ethers, BHT, BHA and BTEX (benzene, toluene, ethylbenzene and xylene) were determined in melon fruit pulps for the first time, with different sensitivities depending on sample and variety. Although the amount of the volatile contaminants in the melon samples were in the order of µg kg -1 , the safety of vegetable crops cultivated near risk areas should be more widely considered. The results showed that this accurate and reproducible method can be useful for routine safety control of fruits and vegetables.

  2. Study of flavour compounds from orange juices by HS-SPME and GC-MS

    Science.gov (United States)

    Schmutzer, G.; Avram, V.; Covaciu, F.; Feher, I.; Magdas, A.; David, L.; Moldovan, Z.

    2013-11-01

    The flavour of the orange juices, which gives the taste and odour of the product, is an important criterion about the products quality for consumers. A fresh single strength and two commercial orange juices (obtained from concentrate) flavour profile were studied using a selective and sensitive gas chromatography - mass spectrometry (GC-MS) analytical system, after a solvent free, single step preconcentration and extraction technique, the headspace solid phase microextraction (HP-SPME). In the studied orange juices 55 flavour compounds were detected and classified as belonging to the esters, alcohols, ketones, monoterpenes and sesquiterpenes chemical families. The fresh single strength orange juice was characterized by high amount of esters, monoterpenes and sesquiterpenes. Limonene and valencene were the most abundant flavours in this fresh natural orange juice. Alcohols and ketones were found in higher concentration in the commercial orange juices made from concentrate, than in the single strength products. Nevertheless, in commercial juices the most abundant flavour was limonene and α-terpineol. The results highlight clear differences between fresh singles strength orange juice and juice from concentrate. The orange juices reconstructed from concentrate, made in Romania, present low quantity of flavour compounds, suggesting the absence or a low rearomatization process, but extraneous components were not detected.

  3. SPME as a promising tool in translational medicine and drug discovery: From bench to bedside.

    Science.gov (United States)

    Goryński, Krzysztof; Goryńska, Paulina; Górska, Agnieszka; Harężlak, Tomasz; Jaroch, Alina; Jaroch, Karol; Lendor, Sofia; Skobowiat, Cezary; Bojko, Barbara

    2016-10-25

    Solid phase microextraction (SPME) is a technology where a small amount of an extracting phase dispersed on a solid support is exposed to the sample for a well-defined period of time. The open-bed geometry and biocompatibility of the materials used for manufacturing of the devices makes it very convenient tool for direct extraction from complex biological matrices. The flexibility of the formats permits tailoring the method according the needs of the particular application. Number of studies concerning monitoring of drugs and their metabolites, analysis of metabolome of volatile as well as non-volatile compounds, determination of ligand-protein binding, permeability and compound toxicity was already reported. All these applications were performed in different matrices including biological fluids and tissues, cell cultures, and in living animals. The low invasiveness of in vivo SPME, ability of using very small sample volumes and analysis of cell cultures permits to address the rule of 3R, which is currently acknowledged ethical standard in R&D labs. In the current review systematic evaluation of the applicability of SPME to studies required to be conduct at different stages of drug discovery and development and translational medicine is presented. The advantages and challenges are discussed based on the examples directly showing given experimental design or on the studies, which could be translated to the models routinely used in drug development process. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Vanguard/rearguard strategy for the evaluation of the degradation of yoghurt samples based on the direct analysis of the volatiles profile through headspace-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Carrillo-Carrión, C; Cárdenas, S; Valcárcel, M

    2007-02-02

    A vanguard/rearguard analytical strategy for the monitoring of the degradation of yoghurt samples is proposed. The method is based on the headspace-gas chromatography-mass spectrometry (HS-GC-MS) instrumental coupling. In this combination, the chromatographic column is firstly used as an interface between the HS and the MS (vanguard mode) avoiding separation of the volatile components by maintaining the chromatographic oven at high, constant temperature. By changing the thermal conditions of the oven, the aldehydes can be properly separated for individual identification/quantification (rearguard mode). In the vanguard method, the quantification of the volatile aldehydes was calculated through partial least square and given as a total index. The rearguard method permits the detection of the aldehydes at concentrations between 12 and 35 ng/g. Both methods were applied to the study of the environmental factors favouring the presence of the volatile aldehydes (C(5)-C(9)) in the yoghurt samples. Principal component analysis of the total concentration of aldehydes with the time (from 0 to 30 days) demonstrates the capability of the HS-MS coupling for the estimation of the quality losses of the samples. The results were corroborated by the HS-GC-MS which also indicates that pentanal was present in the yoghurt from the beginning of the study and the combination of light/oxygen was the most negative influence for sample conservation.

  5. Recent Developments and Applications of Solid Phase Microextraction (SPME in Food and Environmental Analysis—A Review

    Directory of Open Access Journals (Sweden)

    Sybille Merkle

    2015-06-01

    Full Text Available Solid-phase microextraction (SPME is a simple, sensitive, rapid and solvent-free technique for the extraction of analytes from gaseous, liquid and solid samples and takes a leading position among microextraction methods. Application of SPME in sample preparation has been increasing continuously over the last decade. It is most often used as an automatized fiber injection system coupled to chromatographic separation modules for the extraction of volatile and semivolatile organic compounds and also allows for the trace analysis of compounds in complex matrices. Since SPME was first introduced in the early 1990s, several modifications have been made to adapt the procedure to specific application requirements. More robust fiber assemblies and coatings with higher extraction efficiencies, selectivity and stability have been commercialized. Automation and on-line coupling to analytical instruments have been achieved in many applications and new derivatization strategies as well as improved calibration procedures have been developed to overcome existing limitations regarding quantitation. Furthermore, devices using tubes, needles or tips for extraction instead of a fiber have been designed. In the field of food analysis, SPME has been most often applied to fruit/vegetables, fats/oils, wine, meat products, dairy and beverages whereas environmental applications focus on the analysis of air, water, soil and sediment samples.

  6. Headspace solid-phase microextraction-gas chromatographic-time-of-flight mass spectrometric methodology for geographical origin verification of coffee

    International Nuclear Information System (INIS)

    Risticevic, Sanja; Carasek, Eduardo; Pawliszyn, Janusz

    2008-01-01

    Increasing consumer awareness of food safety issues requires the development of highly sophisticated techniques for the authentication of food commodities. The food products targeted for falsification are either products of high commercial value or those produced in large quantities. For this reason, the present investigation is directed towards the characterization of coffee samples according to the geographical origin. The conducted research involves the development of a rapid headspace solid-phase microextraction (HS-SPME)-gas chromatography-time-of-flight mass spectrometry (GC-TOFMS) method that is utilized for the verification of geographical origin traceability of coffee samples. As opposed to the utilization of traditional univariate optimization methods, the current study employs the application of multivariate experimental designs to the optimization of extraction-influencing parameters. Hence, the two-level full factorial first-order design aided in the identification of two influential variables: extraction time and sample temperature. The optimum set of conditions for the two variables was 12 min and 55 deg. C, respectively, as directed by utilization of Doehlert matrix and response surface methodology. The high-throughput automated SPME procedure was completed by implementing a single divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) 50/30 μm metal fiber with excellent durability properties ensuring the completion of overall sequence of coffee samples. The utilization of high-speed TOFMS instrument ensured the completion of one GC-MS run of a complex coffee sample in 7.9 min and the complete list of benefits provided by ChromaTOF software including fully automated background subtraction, baseline correction, peak find and mass spectral deconvolution algorithms was exploited during the data evaluation procedure. The combination of the retention index (RI) system using C 8 -C 40 alkanes and the mass spectral library search was utilized for the

  7. Headspace solid-phase microextraction-gas chromatographic-time-of-flight mass spectrometric methodology for geographical origin verification of coffee

    Energy Technology Data Exchange (ETDEWEB)

    Risticevic, Sanja [Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada); Carasek, Eduardo [Department of Chemistry, Federal University of Santa Catarina, Trindade, Florianopolis, 88040-900, Santa Catarina (Brazil); Pawliszyn, Janusz [Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada)], E-mail: janusz@uwaterloo.ca

    2008-06-09

    Increasing consumer awareness of food safety issues requires the development of highly sophisticated techniques for the authentication of food commodities. The food products targeted for falsification are either products of high commercial value or those produced in large quantities. For this reason, the present investigation is directed towards the characterization of coffee samples according to the geographical origin. The conducted research involves the development of a rapid headspace solid-phase microextraction (HS-SPME)-gas chromatography-time-of-flight mass spectrometry (GC-TOFMS) method that is utilized for the verification of geographical origin traceability of coffee samples. As opposed to the utilization of traditional univariate optimization methods, the current study employs the application of multivariate experimental designs to the optimization of extraction-influencing parameters. Hence, the two-level full factorial first-order design aided in the identification of two influential variables: extraction time and sample temperature. The optimum set of conditions for the two variables was 12 min and 55 deg. C, respectively, as directed by utilization of Doehlert matrix and response surface methodology. The high-throughput automated SPME procedure was completed by implementing a single divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) 50/30 {mu}m metal fiber with excellent durability properties ensuring the completion of overall sequence of coffee samples. The utilization of high-speed TOFMS instrument ensured the completion of one GC-MS run of a complex coffee sample in 7.9 min and the complete list of benefits provided by ChromaTOF software including fully automated background subtraction, baseline correction, peak find and mass spectral deconvolution algorithms was exploited during the data evaluation procedure. The combination of the retention index (RI) system using C{sub 8}-C{sub 40} alkanes and the mass spectral library search was

  8. Quantification of 13 priority polycyclic aromatic hydrocarbons in human urine by headspace solid-phase microextraction gas chromatography-isotope dilution mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Campo, Laura [Department of Occupational and Environmental Health, University of Milan and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan (Italy)], E-mail: laura.campo@unimi.it; Mercadante, Rosa; Rossella, Federica; Fustinoni, Silvia [Department of Occupational and Environmental Health, University of Milan and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan (Italy)

    2009-01-12

    Polycyclic aromatic hydrocarbons (PAHs) are common environmental pollutants in both living and working environments. The aim of this study was the development of a headspace solid-phase microextraction gas chromatography-isotope dilution mass spectrometry (HS-SPME/GC-IDMS) method for the simultaneous quantification of 13 PAHs in urine samples. Different parameters affecting PAHs extraction by HS-SPME were considered and optimized: type/thickness of fiber coatings, extraction temperature/time, desorption temperature/time, ionic strength and sample agitation. The stability of spiked PAHs solutions and of real urine samples stored up to 90 days in containers of different materials was evaluated. In the optimized method, analytes were absorbed for 60 min at 80 deg. C in the sample headspace with a 100 {mu}m polydimethylsiloxane fiber. The method is very specific, with linear range from the limit of quantification to 8.67 x 10{sup 3} ng L{sup -1}, a within-run precision of <20% and a between-run precision of <20% for 2-, 3- and 4-ring compounds and of <30% for 5-ring compounds, trueness within 20% of the spiked concentration, and limit of quantification in the 2.28-2.28 x 10{sup 1} ng L{sup -1} range. An application of the proposed method using 15 urine samples from subjects exposed to PAHs at different environmental levels is shown.

  9. Determination of some volatile compounds in alcoholic beverage by headspace solid-phase microextraction gas chromatography - mass spectrometry

    Science.gov (United States)

    Schmutzer, G.; Avram, V.; Feher, I.; David, L.; Moldovan, Z.

    2012-02-01

    The volatile composition of alcoholic beverage was studied by headspace solid-phase microextraction (HSSPME) method and gas chromatography - mass spectrometry (GC-MS). Some volatile compounds, such as alcohols, esters, terpenes and other are mainly responsible for the flavor of fortified wines and their amounts specify the quality of the alcoholic beverages. From this perspective it is interesting to develop a rapid, selective and sensitive analytical method suitable for simultaneous quantification of the main molecules being responsible for the organoleptic characteristic of alcoholic beverages. Vermouth fortified drink was analyzed in order to characterize the volatile profile. Using the HS-SPME/GC-MS a number of twenty-six volatile compounds from a commercial market alcoholic beverage were identified. The most abundant compounds were m-thymol, o-thymol and eugenol, alongside of the ethyl ester compounds.

  10. Sampling atmospheric pesticides with SPME: Laboratory developments and field study

    International Nuclear Information System (INIS)

    Wang Junxia; Tuduri, Ludovic; Mercury, Maud; Millet, Maurice; Briand, Olivier; Montury, Michel

    2009-01-01

    To estimate the atmospheric exposure of the greenhouse workers to pesticides, solid phase microextraction (SPME) was used under non-equilibrium conditions. Using Fick's law of diffusion, the concentrations of pesticides in the greenhouse can be calculated using pre-determined sampling rates (SRs). Thus the sampling rates (SRs) of two modes of SPME in the lab and in the field were determined and compared. The SRs for six pesticides in the lab were 20.4-48.3 mL min -1 for the exposed fiber and 0.166-0.929 mL min -1 for the retracted fiber. In field sampling, two pesticides, dichlorvos and cyprodinil were detected with exposed SPME. SR with exposed SPME for dichlorvos in the field (32.4 mL min -1 ) was consistent with that in the lab (34.5 mL min -1 ). SR for dichlorvos in the field (32.4 mL min -1 ) was consistent with that in the lab (34.5 mL min -1 ). The trends of temporal concentration and the inhalation exposure were also obtained. - SPME was proved to be a powerful and simple tool for determining pesticides' atmospheric concentration

  11. Determination of residual volatile organic compounds migrated from polystyrene food packaging into food simulant by headspace solid phase micro extraction-gas chromatography

    International Nuclear Information System (INIS)

    Mohd Marsin Sanagi; Ling, Susie Lu; Zalilah Nasir; Wan Aini Wan Ibrahim; Abu Naim, Ahmedy

    2008-01-01

    The residual styrene and other volatile organic compounds (VOCs) present in the polystyrene food packaging are of concern as these compounds have the potential to migrate into the food in contact. This work describes a method for quantitative determination of VOCs, namely styrene, toluene, ethyl benzene, iso-propylbenzene and n-propylbenzene that have migrated from polystyrene food packaging into food stimulant by gas chromatography-flame ionization detection (GC-FID). Headspace solid phase micro extraction (HS-SPME) technique was applied for migration test using water as food stimulant. The effects of extraction variables including sample volume, eluotropic strength, extraction temperature, extraction time, desorption time, sample agitation, and salt addition on the amounts of the extracted analyses were studied to obtain the optimal HS-SPME conditions. The optimized method was applied to test the VOCs migrated from polystyrene bowls and cups at storage temperatures ranging from 24 to 80 degree Celsius for 30 min. Styrene and ethyl benzene were found to migrate from the samples into the food stimulant. The migration of analyze was found to be strongly dependent upon the storage temperature. The HS-SPME is useful as an alternative method to determine the migration of VOCs from food packaging material into food stimulant. (author)

  12. A novel sol-gel-based amino-functionalized fiber for headspace solid-phase microextraction of phenol and chlorophenols from environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Bagheri, Habib [Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)], E-mail: Bagheri@sharif.edu; Babanezhad, Esmaeil; Khalilian, Faezeh [Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)

    2008-05-26

    A novel amino-functionalized polymer was synthesized using 3-(trimethoxysilyl) propyl amine (TMSPA) as precursor and hydroxy-terminated polydimethylsiloxane (OH-PDMS) by sol-gel technology and coated on fused-silica fiber. The synthesis was designed in a way to impart polar moiety into the coating network. The scanning electron microscopy (SEM) images of this new coating showed the homogeneity and the porous surface structure of the film. The efficiency of new coating was investigated for headspace solid-phase microextraction (SPME) of some environmentally important chlorophenols from aqueous samples followed by gas chromatography-mass spectrometry (GC-MS) analysis. Effect of different parameters influencing the extraction efficiency such as extraction temperature, extraction time, ionic strength and pH was investigated and optimized. In order to improve the separation efficiency of phenolic compounds on chromatography column all the analytes were derivatized prior to extraction using acetic anhydride at alkaline condition. The detection limits of the method under optimized conditions were in the range of 0.02-0.05 ng mL{sup -1}. The relative standard deviations (R.S.D.) (n = 6) at a concentration level of 0.5 ng mL{sup -1} were obtained between 6.8 and 10%. The calibration curves of chlorophenols showed linearity in the range of 0.5-200 ng mL{sup -1}. The proposed method was successfully applied to the extraction from spiked tap water samples and relative recoveries were higher than 90% for all the analytes.

  13. Tank 24-C-103 headspace flammability

    International Nuclear Information System (INIS)

    Huckaby, J.L.

    1994-05-01

    Information regarding flammable vapors, gases, and aerosols is presented and interpreted to help resolve the tank 241-C-103 headspace flammability issue. Analyses of recent vapor and liquid samples, as well as visual inspections of the tank headspace, are discussed in the context of tank dynamics. Concern that the headspace of tank 241-C-103 may contain a flammable mixture of organic vapors and an aerosol of combustible organic liquid droplets arises from the presence of a layer of organic liquid in the tank. This organic liquid is believed to have originated in the plutonium-uranium extraction (PUREX) process, having been stored initially in tank 241-C-102 and apparently transferred to tank 241-C-103 in 1975 (Carothers 1988). Analyses of samples of the organic liquid collected in 1991 and 1993 indicate that the primary constituents are tributyl phosphate (TBP) and several semivolatile hydrocarbons (Prentice 1991, Pool and Bean 1994). This is consistent with the premise that the organic waste came from the PUREX process, because the PUREX process used a solution of TBP in a diluent composed of the n-C 11 H 24 to n-C 15 H 32 normal paraffinic hydrocarbons (NPH)

  14. Análise qualitativa de compostos voláteis do headspace de carne cozida de ovinos e caprinos

    Directory of Open Access Journals (Sweden)

    Jossiê Zamperetti Donadel

    2013-11-01

    Full Text Available Este estudo teve como objetivo caracterizar qualitativamente os compostos voláteis (CV do headspace de diferentes músculos de carne cozida de ovinos e caprinos da região do Alto Camaquã, Rio Grande do Sul - Brasil. Os CV do headspace dos músculos cozidos, L. dorsi e V. lateralis de cinco ovinos machos (idade de 6 meses e cinco cabritos machos castrados (idade de 8-9 meses foram analisados pela técnica de microextração em fase sólida (HS-SPME e cromatógrafo a gás acoplado a espectrômetro de massas (GC/MS. Foram encontrados 73 compostos voláteis, dentre eles aldeídos, cetonas e compostos sulfurados, característicos de carne processada termicamente. A partir da fração volátil, foi possível encontrar marcadores que discriminassem as espécies animais estudadas, caracterizando os caprinos por apresentarem, entre outros compostos, terpenos (β-pineno, α-gurjuneno, α-muuroleno, ausentes em ovinos. Alguns compostos discriminaram V. lateralis e L. dorsi de ovinos, como álcool isopropílico, α-pineno, o-xileno, porém não foi possível obter uma diferenciação entre os músculos de caprinos.

  15. Fast quantitation of opioid isomers in human plasma by differential mobility spectrometry/mass spectrometry via SPME/open-port probe sampling interface.

    Science.gov (United States)

    Liu, Chang; Gómez-Ríos, Germán Augusto; Schneider, Bradley B; Le Blanc, J C Yves; Reyes-Garcés, Nathaly; Arnold, Don W; Covey, Thomas R; Pawliszyn, Janusz

    2017-10-23

    Mass spectrometry (MS) based quantitative approaches typically require a thorough sample clean-up and a decent chromatographic step in order to achieve needed figures of merit. However, in most cases, such processes are not optimal for urgent assessments and high-throughput determinations. The direct coupling of solid phase microextraction (SPME) to MS has shown great potential to shorten the total sample analysis time of complex matrices, as well as to diminish potential matrix effects and instrument contamination. In this study, we demonstrate the use of the open-port probe (OPP) as a direct and robust sampling interface to couple biocompatible-SPME (Bio-SPME) fibres to MS for the rapid quantitation of opioid isomers (i.e. codeine and hydrocodone) in human plasma. In place of chromatography, a differential mobility spectrometry (DMS) device was implemented to provide the essential selectivity required to quantify these constitutional isomers. Taking advantage of the simplified sample preparation process based on Bio-SPME and the fast separation with DMS-MS coupling via OPP, a high-throughput assay (10-15 s per sample) with limits of detection in the sub-ng/mL range was developed. Succinctly, we demonstrated that by tuning adequate ion mobility separation conditions, SPME-OPP-MS can be employed to quantify non-resolved compounds or those otherwise hindered by co-extracted isobaric interferences without further need of coupling to other separation platforms. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Role of nanoparticles in analytical solid phase microextraction (SPME)

    NARCIS (Netherlands)

    Zielinska, K.; Leeuwen, van H.P.

    2013-01-01

    Solid phase microextraction (SPME) is commonly used to measure the free concentration of fairly hydrophobic substances in aqueous media on the basis of their partitioning between sample solution and a solid phase. Here we study the role of nanoparticles that may sorb the analyte in the sample

  17. Selected Ion Flow Tube-MS Analysis of Headspace Vapor from Gastric Content for the Diagnosis of Gastro-Esophageal Cancer

    Czech Academy of Sciences Publication Activity Database

    Kumar, S.; Huang, J.; Cushnir, J. R.; Španěl, Patrik; Smith, D.

    2012-01-01

    Roč. 84, č. 21 (2012), s. 9550-9557 ISSN 0003-2700 Institutional support: RVO:61388955 Keywords : SOLID-PHASE MICROEXTRACTION * TRACE GAS-ANALYSIS * CHROMATOGRAPHY-MASS SPECTROMETRY Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.695, year: 2012

  18. Integrated sampling and analysis unit for the determination of sexual pheromones in environmental air using fabric phase sorptive extraction and headspace-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Alcudia-León, M Carmen; Lucena, Rafael; Cárdenas, Soledad; Valcárcel, Miguel; Kabir, Abuzar; Furton, Kenneth G

    2017-03-10

    This article presents a novel unit that integrates for the first time air sampling and preconcentration based on the use of fabric phase sorptive extraction principles. The determination of Tuta absoluta sexual pheromone traces in environmental air has been selected as analytical problem. For this aim, a novel laboratory-built unit made up of commercial brass elements as holder of the sol-gel coated fabric extracting phase has been designed and optimized. The performance of the integrated unit was evaluated analyzing environmental air sampled in tomato crops. The unit can work under sampling and analysis mode which eliminates any need for sorptive phase manipulation prior to instrumental analysis. In the sampling mode, the unit can be connected to a sampling pump to pass the air through the sorptive phase at a controlled flow-rate. In the analysis mode, it is placed in the gas chromatograph autosampler without any instrumental modification. It also diminishes the risk of cross contamination between sampling and analysis. The performance of the new unit has been evaluated using the main components of the sexual pheromone of Tuta absoluta [(3E,8Z,11Z)-tetradecatrien-1-yl acetate and (3E,8Z)-tetradecadien-1-yl acetate] as model analytes. The limits of detection for both compounds resulted to be 1.6μg and 0.8μg, respectively, while the precision (expressed as relative standard deviation) was better than 3.7%. Finally, the unit has been deployed in the field to analyze a number of real life samples, some of them were found positive. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Study on radiolysis products of N,N,N',N'-tetrabutyl-3-oxa-pentanediamide. Pt.1: Qualitative and quantitative analysis of dibutylamine

    International Nuclear Information System (INIS)

    Zhang Xiaolan; Shanghai Univ., Shanghai; Bao Borong; Shanghai Univ., Shanghai; Yang Yanqin; Ye Guoan; Zhang Xianye

    2005-01-01

    The study on radiolysis products of gamma-irradiated N,N,N',N'-tetrabutyl-3-oxa-pentane-diamide (TBOPDA) is very useful towards the extractant stability. IR and headspace solid-phase microextraction combined with gas chromatography/mass spectrometry (SPME-GC/MS) are used in the research. By comparisons with standard substances, dibutylamine and N,N-dibutylformamide are comfirmed to be the major radiolysis products. The influences of irradiation on TBOPDA and dibutylamine are quantitated by using headspace SPME-GC and HPLC. According to the experiment results, the possible ways of degradation are also proposed. (authors)

  20. Characterisation of volatile profile and sensory analysis of fresh-cut "Radicchio di Chioggia" stored in air or modified atmosphere.

    Science.gov (United States)

    Cozzolino, Rosaria; Martignetti, Antonella; Pellicano, Mario Paolo; Stocchero, Matteo; Cefola, Maria; Pace, Bernardo; De Giulio, Beatrice

    2016-02-01

    The volatile profile of two hybrids of "Radicchio di Chioggia", Corelli and Botticelli, stored in air or passive modified atmosphere (MAP) during 12 days of cold storage, was monitored by solid phase micro-extraction (SPME) GC-MS. Botticelli samples were also subjected to sensory analysis. Totally, 61 volatile organic compounds (VOCs) were identified in the headspace of radicchio samples. Principal component analysis (PCA) showed that fresh product possessed a metabolic content similar to that of the MAP samples after 5 and 8 days of storage. Projection to latent structures by partial least squares (PLS) regression analysis showed the volatiles content of the samples varied depending only on the packaging conditions. Specifically, 12 metabolites describing the time evolution and explaining the effects of the different storage conditions were highlighted. Finally, a PCA analysis revealed that VOCs profile significantly correlated with sensory attributes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. GNS Castor V/21 Headspace Gas Sampling 2014

    Energy Technology Data Exchange (ETDEWEB)

    Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-01

    Prior to performing an internal visual inspection, samples of the headspace gas of the GNS Castor V/21 cask were taken on June 12, 2014. These samples were taken in support of the CREIPI/Japanese nuclear industry effort to validate fuel integrity without visual inspection by measuring the 85Kr content of the cask headspace

  2. Headspace profiling of cocaine samples for intelligence purposes.

    Science.gov (United States)

    Dujourdy, Laurence; Besacier, Fabrice

    2008-08-06

    A method for determination of residual solvents in illicit hydrochloride cocaine samples using static headspace-gas chromatography (HS-GC) associated with a storage computerized procedure is described for the profiling and comparison of seizures. The system involves a gas chromatographic separation of 18 occluded solvents followed by fully automatic data analysis and transfer to a PHP/MySQL database. First, a fractional factorial design was used to evaluate the main effects of some critical method parameters (salt choice, vial agitation intensity, oven temperature, pressurization and loop equilibration) on the results with a minimum of experiments. The method was then validated for tactical intelligence purposes (batch comparison) via several studies: selection of solvents and mathematical comparison tool, reproducibility and "cutting" influence studies. The decision threshold to determine the similarity of two samples was set and false positives and negatives evaluated. Finally, application of the method to distinguish geographical origins is discussed.

  3. Application of HS-SPME-GC-MS method for the detection of active moulds on historical parchment.

    Science.gov (United States)

    Sawoszczuk, Tomasz; Syguła-Cholewińska, Justyna; Del Hoyo-Meléndez, Julio M

    2017-03-01

    The goal of this work was to analyse the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on parchment samples, in search of particular volatiles mentioned in the literature as indicators of active mould growth. First, the growth of various moulds on samples of parchment was assessed. Those species that showed collagenolytic activity were then inoculated on two types of media: samples of parchment placed on media and on media containing amino acids that are elements of the structure of collagen. All samples were prepared inside 20-ml vials (closed system). In the first case, the media did not contain any sources of organic carbon, nitrogen, or sulphur, i.e. parchment was the only nutrient for the moulds. A third type of sample was historical parchment prepared in a Petri dish without a medium and inoculated with a collagenolytically active mould (open system). The MVOCs emitted by moulds were sampled with the headspace-SPME method. Volatiles extracted on DVB/CAR/PDMS fibres were analysed in a gas chromatography-mass spectrometry system. Qualitative and quantitative analyses of chromatograms were carried out in search of indicators of metabolic activity. The results showed that there are three groups of volatiles that can be used for the detection of active forms of moulds on parchment objects. To the best of our knowledge, this is the first work to measure MVOCs emitted by moulds growing on parchment.

  4. Analysis of acrylonitrile, 1,3-butadiene, and related compounds in acrylonitrile-butadiene-styrene copolymers for kitchen utensils and children's toys by headspace gas chromatography/mass spectrometry.

    Science.gov (United States)

    Ohno, Hiroyuki; Kawamura, Yoko

    2010-01-01

    A headspace gas chromatography/mass spectrometry method was developed for the simultaneous determination of the residual levels of acrylonitrile (AN), 1,3-butadiene (1,3-BD), and their related compounds containing propionitrile (PN) and 4-vinyl-1-cyclohexene (4-VC) in acrylonitrile-butadiene-styrene (ABS) copolymers for kitchen utensils and children's toys. A sample was cut into small pieces, then N,N-dimethylacetamide and an internal standard were added in a sealed headspace vial. The vial was incubated for 1 h at 90 degrees C and the headspace gas was analyzed by gas chromatography/mass spectrometry. The recovery rates of the analytes were 93.3-101.8% and the coefficients of variation were 0.3-6.5%. In ABS copolymers, the levels were 0.3-50.4 microg/g for AN, ND-4.5 microg/g for PN, 0.06-1.58 microg/g for 1,3-BD, and 1.1-295 microg/g for 4-VC. The highest level was found for 4-VC, which is a dimer of 1,3-BD, and the next highest was for AN, which is one of the monomers of the ABS copolymer. Furthermore, the method was also applied to acrylonitrile-styrene (AS) copolymers and polystyrenes (PS) for kitchen utensils, and nitrile-butadiene rubber (NBR) gloves. In AS copolymers, AN and PN were detected at 16.8-54.5 and 0.8-6.9 microg/g, respectively. On the other hand, the levels in PS and NBR samples were all low.

  5. Determination of 3-chloro-1,2-propanediol in polyamideamine epichlorohydrin resin solution by reaction-based headspace gas chromatography.

    Science.gov (United States)

    Yan, Ning; Wan, Xiao-Fang; Chai, Xin-Sheng; Chen, Run-Quan

    2018-04-01

    We report on a headspace gas chromatographic method for determining the content of 3-chloro-1,2-propanediol in polyamideamine epichlorohydrin resin solution. It was based on quantitatively converting 3-chloro-1,2-propanediol to formaldehyde by periodate oxidation in a closed headspace sample vial at a room temperature for 10 min, and then to methanol by borohydride reduction at 90°C for 40 min followed by the headspace gas chromatographic measurement. The results showed that the present method has an excellent measurement precision (relative standard deviation < 2.60%) and accuracy (recoveries from 96.4-102%) in 3-chloro-1,2-propanediol analysis. The limit of quantitation was 0.031 mg/mL. It is simple and suitable for determining the 3-chloro-1,2-propanediol content in polyamideamine epichlorohydrin resin solution. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Rapid sampling of BTEX in air by SPME in the city of Nice and at the Nice-Cote d'Azur airport

    International Nuclear Information System (INIS)

    Tumbiolo, S.; Gal, J.F.; Maria, P.Ch.; Laborde, P.; Teton, S.

    2006-01-01

    This article presents the results of a tentative application of Solid Phase Micro Extraction (SPME) to the analysis of BTEX (benzene, toluene, ethyl-benzene and xylenes) at the μg/m 3 level in indoor and outdoor air. The salient features of the method validation are reported. Sampling by QUALITAIR using Radiello passive samplers, was carried out from 2001 to 2004 in the city of Nice and its airport. Urban traffic impact was proved, but a link between BTX concentrations and the variations of airport activities was not clearly established. During the same period, several samplings were performed using SPME. Taking into account the short (30 minutes) sampling time, rapid changes of BTEX concentrations were evidenced, as for example the start of airplane engines. As field studies have shown, SPME technique appears as a method of choice for fast qualitative analysis and quantitative determination of Volatile Organic Compounds (VOC). The small dimensions of the SPME sampling system and the short sampling time let envisage its utilisation for the rapid diagnostic and the monitoring of indoor air quality. (author)

  7. Tank vapor characterization project - Tank 241-U-112 headspace gas and vapor characterization: Results for homogeneity samples collected on December 6, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Sklarew, D.S.; Pool, K.H.; Evans, J.C.; Hayes, J.C. [and others

    1997-09-01

    This report presents the results of analyses of samples taken from the headspace of waste storage tank 241-U-112 (Tank U-112) at the Hanford Site in Washington State. Samples were collected to determine the homogeneity of selected inorganic and organic headspace constitutents. Two risers (Riser 3 and Riser 6) were sampled at three different elevations (Bottom, Middle, and Top) within the tank. Tank headspace samples were collected by SGN Eurisys Service Corporation (SESC) and were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan.

  8. Headspace vapor characterization of Hanford waste tank 241-U-108: Results from samples collected on 8/29/95

    International Nuclear Information System (INIS)

    Thomas, B.L.; Clauss, T.W.; Evans, J.C.; McVeety, B.D.; Pool, K.H.; Olsten, K.B.; Fruchter, J.S.; Ligotke, M.W.

    1996-05-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-U-108 (Tank U-108) at the Hanford Site in Washington State. The results described in the report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC

  9. Analysis of honeybush tea (Cyclopia spp.) volatiles by comprehensive two-dimensional gas chromatography using a single-stage thermal modulator.

    Science.gov (United States)

    Ntlhokwe, Gaalebalwe; Tredoux, Andreas G J; Górecki, Tadeusz; Edwards, Matthew; Vestner, Jochen; Muller, Magdalena; Erasmus, Lené; Joubert, Elizabeth; Christel Cronje, J; de Villiers, André

    2017-07-01

    The applicability of comprehensive two-dimensional gas chromatography (GC×GC) using a single-stage thermal modulator was explored for the analysis of honeybush tea (Cyclopia spp.) volatile compounds. Headspace solid phase micro-extraction (HS-SPME) was used in combination with GC×GC separation on a non-polar × polar column set with flame ionisation (FID) detection for the analysis of fermented Cyclopia maculata, Cyclopia subternata and Cyclopia genistoides tea infusions of a single harvest season. Method optimisation entailed evaluation of the effects of several experimental parameters on the performance of the modulator, the choice of columns in both dimensions, as well as the HS-SPME extraction fibre. Eighty-four volatile compounds were identified by co-injection of reference standards. Principal component analysis (PCA) showed clear differentiation between the species based on their volatile profiles. Due to the highly reproducible separations obtained using the single-stage thermal modulator, multivariate data analysis was simplified. The results demonstrate both the complexity of honeybush volatile profiles and the potential of GC×GC separation in combination with suitable data analysis techniques for the investigation of the relationship between sensory properties and volatile composition of these products. The developed method therefore offers a fast and inexpensive methodology for the profiling of honeybush tea volatiles. Graphical abstract Surface plot obtained for the GC×GC-FID analysis of honeybush tea volatiles.

  10. Determination of N-vinyl-2-pyrrolidone and N-methyl-2-pyrrolidone in drugs using polypyrrole-based headspace solid-phase microextraction and gas chromatography-nitrogen-phosphorous detection.

    Science.gov (United States)

    Mehdinia, Ali; Ghassempour, Alireza; Rafati, Hasan; Heydari, Rouhollah

    2007-03-21

    A headspace solid-phase microextraction and gas chromatography-nitrogen-phosphorous detection (HS-SPME-GC-NPD) method using polypyrrole (PPy) fibers has been introduced to determine two derivatives of pyrrolidone; N-vinyl-2-pyrrolidone (NVP) and N-methyl-2-pyrrolidone (NMP). Two types of PPy fibers, prepared using organic and aqueous media, were compared in terms of extraction efficiency and thermal stability. It was found that PPy film prepared using organic medium (i.e. acetonitrile) had higher extraction efficiency and more thermal stability compared to the film prepared in aqueous medium. To enhance the sensitivity of HS-SPME, the effects of pH, ionic strength, extraction time, extraction temperature and the headspace volume on the extraction efficiency were optimized. Using the results of this research, high sensitivity and selectivity had been achieved due to the combination of the high extraction efficiency of PPy film prepared in organic medium and the high sensitivity and selectivity of nitrogen-phosphorous detection. Linear range of the analytes was found to be between 1.0 and 1000 microg L(-1) with regression coefficients (R(2)) of 0.998 and 0.997 for NVP and NMP, consequently. Limits of detection (LODs) were 0.074 and 0.081 microg L(-1) for NVP and NMP, respectively. Relative standard deviation (R.S.D.) for five replications of analyses was found to be less than 6.0%. In real samples the mean recoveries were 94.81% and 94.15% for NVP and NMP, respectively. The results demonstrated the suitability of the HS-SPME technique for analyzing NVP and NMP in two different pharmaceutical matrices. In addition, the method was used for simultaneous detection of NVP, 2-pyrrolidone (2-Pyr), gamma-butyrolactone (GBL) and ethanolamine (EA) compounds.

  11. Test plan for headspace gas concentration measurement and headspace ventilation rate measurement for DCRTs 241-A-244, 241-BX-244, 241-S-244, 241-TX-244

    International Nuclear Information System (INIS)

    Bauer, R.E.

    1998-01-01

    This test plan provides the directions to characterize the headspace gas concentrations and the headspace ventilation rate for double contained receiver tanks 241-A-244, 241-BX-244, 241-S-244, and 241-TX-244

  12. Headspace solid-phase microextraction coupled to gas chromatography-tandem mass spectrometry for the determination of haloanisoles in sparkling (cava and cider) and non-sparkling (wine) alcoholic beverages.

    Science.gov (United States)

    Ruiz-Delgado, Ana; Arrebola-Liébanas, Francisco Javier; Romero-González, Roberto; López-Ruiz, Rosalía; Garrido Frenich, Antonia

    2016-10-01

    A highly sensitive analytical method was developed to determine 2,4,6-trichloroanisole (TCA), 2,3,4,6-tetrachloroanisole (TeCA), 2,4,6-tribromoanisole (TBA) and 2,3,4,5,6-pentachloroanisole (PCA) in sparkling alcoholic beverages. The method was based on the use of headspace solid-phase microextraction (HS-SPME) using a polydimethylsiloxane (PDMS) fibre. It was coupled to gas chromatography-triple quadrupole tandem mass spectrometry (GC-QqQ-MS/MS) for the detection and quantification of the target haloanisoles. The method was fully automated and no sample preparation was needed. The method was validated for alcoholic beverages. The influence of CO 2 on the extraction efficiency was also evaluated for the studied sparkling drinks (cava and cider). All the calibration curves showed good linearity (R 2  > 0.98) within the tested range (1-50 ng l -1 ). Recoveries were evaluated at three different levels (1, 5 and 50 ng l -1 ) and were always between 71% and 119%. Precision was expressed as relative standard deviation (RSD), and was evaluated as intra- and inter-day precisions, with values ≤ 22% in both cases. Limits of quantitation (LOQs) were ≤ 0.91 ng l -1 , which are below the sensory threshold levels for such compounds in humans. The validated method was applied to commercial samples, 10 cavas and 10 ciders, but it was also used for the analysis of nine red wines and four white wines, demonstrating the further applicability of the proposed method to non-sparkling beverages. TCA was detected in most samples at up to 0.45 ng l -1 .

  13. Determination of sulfur dioxide in wine using headspace gas chromatography and electron capture detection.

    Science.gov (United States)

    Aberl, A; Coelhan, M

    2013-01-01

    Sulfites are routinely added as preservatives and antioxidants in wine production. By law, the total sulfur dioxide content in wine is restricted and therefore must be monitored. Currently, the method of choice for determining the total content of sulfur dioxide in wine is the optimised Monier-Williams method, which is time consuming and laborious. The headspace gas chromatographic method described in this study offers a fast and reliable alternative method for the detection and quantification of the sulfur dioxide content in wine. The analysis was performed using an automatic headspace injection sampler, coupled with a gas chromatograph and an electron capture detector. The method is based on the formation of gaseous sulfur dioxide subsequent to acidification and heating of the sample. In addition to free sulfur dioxide, reversibly bound sulfur dioxide in carbonyl compounds, such as acetaldehyde, was also measured with this method. A total of 20 wine samples produced using diverse grape varieties and vintages of varied provenance were analysed using the new method. For reference and comparison purposes, 10 of the results obtained by the proposed method were compared with those acquired by the optimised Monier-Williams method. Overall, the results from the headspace analysis showed good correlation (R = 0.9985) when compared with the conventional method. This new method requires minimal sample preparation and is simple to perform, and the analysis can also be completed within a short period of time.

  14. Quantification of 2-acetyl-1-pyrroline in rice by stable isotope dilution assay through headspace solid-phase microextraction coupled to gas chromatography-tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Maraval, Isabelle [UMR Qualisud, CIRAD, 73 Rue J. F. Breton, 34398 Montpellier Cedex 5 (France); UMR Qualisud, Universite Montpellier 2, place E. Bataillon, 34095 Montpellier Cedex 5 (France); Sen, Kemal [Department of Food Engineering, Faculty of Agriculture, University of Cukurova, 01330 Adana (Turkey); Agrebi, Abdelhamid; Menut, Chantal; Morere, Alain [UMR 5247, Institut des Biomolecules Max Mousseron (IBMM), CNRS, Universites Montpellier 2 et 1, Ecole Nationale Superieure de Chimie de Montpellier, 8 Rue de l' Ecole Normale, 34296 Montpellier Cedex 5 (France); Boulanger, Renaud [UMR Qualisud, CIRAD, 73 Rue J. F. Breton, 34398 Montpellier Cedex 5 (France); Gay, Frederic [CIRAD, DORAS Centre, Research and Development Building, Kasetsart University, Bangkok 10900 (Thailand); Mestres, Christian [UMR Qualisud, CIRAD, 73 Rue J. F. Breton, 34398 Montpellier Cedex 5 (France); Gunata, Ziya, E-mail: zgunata@univ-montp2.fr [UMR Qualisud, Universite Montpellier 2, place E. Bataillon, 34095 Montpellier Cedex 5 (France)

    2010-08-24

    A new and convenient synthesis of 2-acetyl-1-pyrroline (2AP), a potent flavor compound in rice, and its ring-deuterated analog, 2-acetyl-1-d{sub 2}-pyrroline (2AP-d{sub 2}), was reported. A stable isotope dilution assay (SIDA), involving headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-positive chemical ionization-ion trap-tandem mass spectrometry (GC-PCI-IT-MS-MS), was developed for 2AP quantification. A divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was used for HS-SPME procedure and parameters affecting analytes recovery, such as extraction time and temperature, pH and salt, were studied. The repeatability of the method (n = 10) expressed as relative standard deviation (RSD) was 11.6%. A good linearity was observed from 5.9 to 779 ng of 2AP (r{sup 2} = 0.9989). Limits of detection (LOD) and quantification (LOQ) for 2AP were 0.1 and 0.4 ng g{sup -1} of rice, respectively. The recovery of spiked 2AP from rice matrix was almost complete. The developed method was applied to the quantification of 2AP in aerial parts and grains of scented and non-scented rice cultivars.

  15. Monitoring of persistent organic pollutants in seawater of the Pearl River Estuary with rapid on-site active SPME sampling technique

    International Nuclear Information System (INIS)

    Huang, Siming; He, Shuming; Xu, Hao; Wu, Peiyan; Jiang, Ruifen; Zhu, Fang; Luan, Tiangang; Ouyang, Gangfeng

    2015-01-01

    An on-site active solid-phase microextraction (SPME) sampling technique coupled with gas chromatography-mass spectrometry (GC–MS) for sampling and monitoring 16 polycyclic aromatic hydrocarbons (PAHs) and 8 organochlorine pesticides (OCPs) in seawater was developed. Laboratory experiments demonstrated that the sampling-rate calibration method was practical and could be used for the quantification of on-site sampling. The proposed method was employed for field tests which covered large amounts of water samples in the Pearl River Estuary in rainy and dry seasons. The on-site SPME sampling method can avoid the contamination of sample, the losses of analytes during sample transportation, as well as the usage of solvent and time-consuming sample preparation process. Results indicated that the technique with the designed device can address the requirement of modern environment water analysis. In addition, the sources, bioaccumulation and potential risk to human of the PAHs and OCPs in seawater of the Pearl River Estuary were discussed. - Highlights: • SPME on-site active sampling technique was developed and validated. • The technique was employed for field tests in the Pearl River Estuary. • 16 PAHs and 8 OCPs in the seawater of Pearl River Estuary were monitored. • The potential risk of the PAHs and OCPs in Pearl River Estuary were discussed. - An on-site active SPME sampling technique was developed and successfully applied for sampling and monitoring 16 PAHs and 8 OCPs in the Pearl River Estuary

  16. Headspace solid phase microextraction--GC/C-IRMS for delta13CVPDB measurements of mono-aromatic hydrocarbons using EA-IRMS calibration.

    Science.gov (United States)

    Ebongué, Véronique Woule; Geypens, Benny; Berglund, Michael; Taylor, Philip

    2009-03-01

    This work aims at comparing the delta(13)C(VPDB) of mono-aromatic hydrocarbons benzene, toluene, ethylbenzene and xylene isomers (BTEX) measured by elemental analyser (EA)-isotope ratio mass spectrometer (IRMS) with the delta(13)C(VPDB) measured on the same compounds by headspace solid phase microextraction - GC/C-IRMS (hSPME - GC/C-IRMS) with the final goal of using these compounds as internal standards on the latter system. The EA-IRMS measurements were done using calcium and lithium carbonate isotopic reference materials: NBS19 and L-SVEC for establishing the delta(13)C(VPDB) scale. The EA-IRMS measurements with helium dilution of a set of five reference materials (USGS40, USGS41, IAEA-CH-6, IAEA-CH-3 and IAEA-601) show systematic bias of 1 per thousand relative to their assigned values. This bias due to the dilution mechanism in the used ConfloII interface device could not be avoided. As the selected hydrocarbons: BTEX could not be analysed by EA-IRMS without helium dilution, their delta(13)C(VPDB) must be corrected from this observed bias using an external calibration. The CO(2) gas calibrated using EA-IRMS without helium dilution, was used as an in-house reference for the delta(13)C(VPDB) measurements of the BTEX by the hSPME - GC/C-IRMS system. The comparison made between the delta(13)C(VPDB) measured on the same BTEX compounds by EA-IRMS (with external calibration) and by hSPME - GC/C-IRMS techniques showed good agreement.

  17. Headspace gas and vapor characterization summary for the 43 vapor program suspect tanks

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    During the time period between February 1994 and September 1995, Westinghouse Hanford Company (WHC) sampled the waste tank headspace of 43 single-shell tanks for a variety of gaseous and/or volatile and semi-volatile compounds. This report summarizes the results of analyses of those sampling activities with respect to both the Priority 1 Safety Issues and relative to the detection in the headspace of significant concentrations of target analytes relating to worker breathing space consideration as recommended by the Pacific Northwest Laboratory (PNL) Toxicology Review Panel. The information contained in the data tables was abstracted from the vapor sampling and analysis tank characterization reports. Selected results are tabulated and summarized. Sampling equipment and methods, as well as sample analyses, are briefly described. Vapor sampling of passively ventilated single-shell tanks (tanks C-105, C-106, and SX-106 were sampled and are actively ventilated) has served to highlight or confirm tank headspace conditions associated with both priority 1 safety issues and supports source term analysis associated with protecting worker health and safety from noxious vapors

  18. Selective molecularly imprinted polymer combined with restricted access material for in-tube SPME/UHPLC-MS/MS of parabens in breast milk samples

    International Nuclear Information System (INIS)

    Souza, Israel D.; Melo, Lidervan P.; Jardim, Isabel C.S.F.; Monteiro, Juliana C.S.; Nakano, Ana Marcia S.; Queiroz, Maria Eugênia C.

    2016-01-01

    A new molecularly imprinted polymer modified with restricted access material (a hydrophilic external layer), (MIP-RAM) was synthesized via polymerization in situ in an open fused silica capillary. This stationary phase was used as sorbent for in-tube solid phase microextraction (in-tube SPME) to determine parabens in breast milk samples by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Scanning electron micrographs (SEM) illustrate MIP surface modification after glycerol dimethacrylate (hydrophilic monomer) incorporation. The interaction between parabens and MIP-RAM was investigated by Fourier-transform infrared (FTIR) spectroscopy. The Scatchard plot for MIP-RAM presented two linear parts with different slopes, illustrating binding sites with high- and low-affinity. Endogenous compounds exclusion from the MIP-RAM capillary was demonstrated by in-tube SPME/LC-UV assays carried out with blank milk samples. The in-tube SPME/UHPLC-MS/MS method presented linear range from 10 ng mL"−"1 (LLOQ) to 400 ng mL"−"1 with coefficients of determination higher than 0.99, inter-assay precision with coefficient of variation (CV) values ranging from 2 to 15%, and inter-assay accuracy with relative standard deviation (RSD) values ranging from −1% to 19%. Analytical validation parameters attested that in-tube SPME/UHPLC-MS/MS is an appropriate method to determine parabens in human milk samples to assess human exposure to these compounds. Analysis of breast milk samples from lactating women demonstrated that the proposed method is effective. - Highlights: • Molecularly imprinted polymer modified with a hydrophilic external layer (RAM-MIP) was synthesized in a silica capillary. • RAM-MIP capillary, used as sorbent for in-tube SPME, established specific interaction with parabens present in milk samples. • The matrix components that interacted only with the hydrophilic external layer (non-adsorptive network) were excluded. • The

  19. Selective molecularly imprinted polymer combined with restricted access material for in-tube SPME/UHPLC-MS/MS of parabens in breast milk samples

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Israel D.; Melo, Lidervan P. [Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Jardim, Isabel C.S.F. [Instituto de Química, Universidade Estadual de Campinas, Campinas, SP (Brazil); Monteiro, Juliana C.S.; Nakano, Ana Marcia S. [Escola de Enfermagem de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Queiroz, Maria Eugênia C., E-mail: mariaeqn@ffclrp.usp.br [Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2016-08-17

    A new molecularly imprinted polymer modified with restricted access material (a hydrophilic external layer), (MIP-RAM) was synthesized via polymerization in situ in an open fused silica capillary. This stationary phase was used as sorbent for in-tube solid phase microextraction (in-tube SPME) to determine parabens in breast milk samples by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Scanning electron micrographs (SEM) illustrate MIP surface modification after glycerol dimethacrylate (hydrophilic monomer) incorporation. The interaction between parabens and MIP-RAM was investigated by Fourier-transform infrared (FTIR) spectroscopy. The Scatchard plot for MIP-RAM presented two linear parts with different slopes, illustrating binding sites with high- and low-affinity. Endogenous compounds exclusion from the MIP-RAM capillary was demonstrated by in-tube SPME/LC-UV assays carried out with blank milk samples. The in-tube SPME/UHPLC-MS/MS method presented linear range from 10 ng mL{sup −1} (LLOQ) to 400 ng mL{sup −1} with coefficients of determination higher than 0.99, inter-assay precision with coefficient of variation (CV) values ranging from 2 to 15%, and inter-assay accuracy with relative standard deviation (RSD) values ranging from −1% to 19%. Analytical validation parameters attested that in-tube SPME/UHPLC-MS/MS is an appropriate method to determine parabens in human milk samples to assess human exposure to these compounds. Analysis of breast milk samples from lactating women demonstrated that the proposed method is effective. - Highlights: • Molecularly imprinted polymer modified with a hydrophilic external layer (RAM-MIP) was synthesized in a silica capillary. • RAM-MIP capillary, used as sorbent for in-tube SPME, established specific interaction with parabens present in milk samples. • The matrix components that interacted only with the hydrophilic external layer (non-adsorptive network) were excluded.

  20. An interior needle electropolymerized pyrrole-based coating for headspace solid-phase dynamic extraction

    Energy Technology Data Exchange (ETDEWEB)

    Bagheri, Habib [Department of Chemistry, Sharif University of Technology, Azadi Av., P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)], E-mail: bagheri@sharif.edu; Babanezhad, Esmaeil; Khalilian, Faezeh [Department of Chemistry, Sharif University of Technology, Azadi Av., P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)

    2009-02-23

    A headspace solid-phase dynamic extraction (HS-SPDE) technique was developed by the use of polypyrrole (PPy) sorbent, electropolymerized inside the surface of a needle, as a possible alternative to solid-phase microextraction (SPME). Thermal desorption was subsequently, employed to transfer the extracted analytes into the injection port of a gas chromatography-mass spectrometry (GC-MS). The PPy sorbent including polypyrrole-dodecyl sulfate (PPy-DS) was deposited on the interior surface of a stainless steel needle from the corresponding aqueous electrolyte by applying a constant deposition potential. The homogeneity and the porous surface structure of the coating were examined using the scanning electron microscopy (SEM). The developed method was applied to the trace level extraction of some polycyclic aromatic hydrocarbons (PAHs) from aqueous sample. In order to enhance the extraction efficiency and increase the partition coefficient of analytes, the stainless steel needle was cooled at 5 deg. C, while the sample solution was kept at 80 deg. C. Optimization of influential experimental conditions including the voltage of power supply, the time of PPy electrodeposition, the extraction temperature, the ionic strength and the extraction time were also investigated. The detection limits of the method under optimized conditions were in the range of 0.002-0.01 ng mL{sup -1}. The relative standard deviations (R.S.D.) at a concentration level of 0.1 ng mL{sup -1} were obtained between 7.54 and 11.4% (n = 6). The calibration curves of PAHs showed linearity in the range of 0.01-10 ng mL{sup -1}. The proposed method was successfully applied to the extraction of some selected PAHs from real-life water samples and the relative recoveries were higher than 90% for all the analytes.

  1. EVALUACIÓN DE DES, FSC Y SPME/CG-MS PARA LA EXTRACCIÓN Y DETERMINACIÓN DE COMPUESTOS RESPONSABLES DEL AROMA DE CAFÉ TOSTADO DE VILCABAMBA - ECUADOR

    Directory of Open Access Journals (Sweden)

    Jorge G. Figueroa

    2016-07-01

    Full Text Available The aim of this study was to compare the usefulness of three extraction methods: solid-phase microextraction (SPME with four different coating (PDMS, PDMS/DVB, DVB/CAR/PDMS and PA, supercritical fluid extraction with carbon dioxide (SCF and simultaneous distillation and extraction (SDE for isolation of flavor compounds from roasted ground coffee (Coffea arabica L. var. Typica of Vilcabamba (Ecuador. Identification and characterization of volatile compounds were achieved using gas chromatography / mass spectrometry (GC-MS. Analysis of variance and principal components analysis was done. For the SPME method the coating material affect the amount and concentration of compounds extracted, the DVB/CAR/PDMS coating provided the most representative aroma extract (44 compounds were identified. The SCF method allowed extracting a higher amount of compounds and also their identification by GC-MS (72 that SDE (64 and SPME (57, in addition provide higher extractions. The acetic acid, caffeine, furfuryl alcohol, furfural, 5-methylfurfural, butylated hydroxytoluene and maltol were the compounds with higher concentrations found with SPME and SDE, with SCF were found higher concentration to compounds with high molecular weights (> 194 g mol-1. Preferably SPME-DVB/CAR/PDMS method should be used for a characterization of coffee aroma compounds.

  2. Determination of 1,3-dichloro-2-propanol and 3-chloro-1,2-propandiol in soy sauce by headspace derivatization solid-phase microextraction combined with gas chromatography-mass spectrometry.

    Science.gov (United States)

    Lee, Maw-Rong; Chiu, Tzu-Chun; Dou, Jianpeng

    2007-05-22

    This study proposes a method for identifying 1,3-dichloro-2-propanol and 3-chloro-1,2-propandiol in aqueous matrices by using headspace on-fiber derivatization following solid-phase microextraction combined with gas chromatography-mass spectrometry. The optimized SPME experimental procedures for extracting 1,3-dichloro-2-propanol and 3-chloro-1,2-propandiol in aqueous solutions involved a 85 microm polyacrylate-coated fiber at pH 6, a sodium chloride concentration of 0.36 g mL(-1), extraction at 50 degrees C for 15 min and desorption of analytes at 260 degrees C for 3 min. Headspace derivatization was conducted in a laboratory-made design with N-methyl-N-(trimethylsilyl)-trifluoroacetamide vapor following solid-phase microextraction by using 3 microL N-methyl-N-(trimethylsilyl)-trifluoroacetamide at an oil bath temperature of 230 degrees C for 40 s. This method had good repeatability (R.S.D.s or = 0.9972) for ultrapure water and soy sauce samples that were spiked with two analytes. Detection limits were obtained at the ng mL(-1). The result demonstrated that headspace on-fiber derivatization following solid-phase microextraction was a simple, fast and accurate technique for identifying trace 1,3-dichloro-2-propanol and 3-chloro-1,2-propandiol in soy sauce.

  3. [Determination of olive oil content in olive blend oil by headspace gas chromatography-mass spectrometry].

    Science.gov (United States)

    Jiang, Wanfeng; Zhang, Ning; Zhang, Fengyan; Yang, Zhao

    2017-07-08

    A method for the determination of the content of olive oil in olive blend oil by headspace gas chromatography-mass spectrometry (SH-GC/MS) was established. The amount of the sample, the heating temperature, the heating time, the amount of injection, the injection mode and the chromatographic column were optimized. The characteristic compounds of olive oil were found by chemometric method. A sample of 1.0 g was placed in a 20 mL headspace flask, and heated at 180℃ for 2700 s. Then, 1.0 mL headspace gas was taken into the instrument. An HP-88 chromatographic column was used for the separation and the analysis was performed by GC/MS. The results showed that the linear range was 0-100%(olive oil content). The linear correlation coefficient ( r 2 ) was more than 0.995, and the limits of detection were 1.26%-2.13%. The deviations of olive oil contents in the olive blend oil were from -0.65% to 1.02%, with the relative deviations from -1.3% to 6.8% and the relative standard deviations from 1.18% to 4.26% ( n =6). The method is simple, rapid, environment friendly, sensitive and accurate. It is suitable for the determination of the content of olive oil in olive blend oil.

  4. Polypyrrole nanowire as an excellent solid phase microextraction fiber for bisphenol A analysis in food samples followed by ion mobility spectrometry.

    Science.gov (United States)

    Kamalabadi, Mahdie; Mohammadi, Abdorreza; Alizadeh, Naader

    2016-08-15

    A polypyrrole nanowire coated fiber was prepared and used in head-space solid phase microextraction coupled with ion mobility spectrometry (HS-SPME-IMS) to the analysis of bisphenol A (BPA) in canned food samples, for the first time. This fiber was synthesized by electrochemical oxidation of the monomer in aqueous solution. The fiber characterization by scanning electron microscopy (SEM) revealed that the new fiber exhibited two-dimensional structures with a nanowire morphology. The effects of important extraction parameters on the efficiency of HS-SPME were investigated and optimized. Under the optimum conditions, the linearity of 10-150ngg(-1) and limit of detection (based on S/N=3) of 1ngg(-1) were obtained in BPA analysis. The repeatability (n=5) expressed as the relative standard deviation (RSD%) was 5.8%. At the end, the proposed method was successfully applied to determine BPA in various canned food samples (peas, corns, beans). Relative recoveries were obtained 93-96%. Method validation was conducted by comparing our results with those obtained through HPLC with fluorescence detection (FLD). Compatible results indicate that the proposed method can be successfully used in BPA analysis. This method is simple and cheaper than chromatographic methods, with no need of extra organic solvent consumption and derivatization prior to sample introduction. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Analysis of volatile organic compounds in compost samples: A potential tool to determine appropriate composting time.

    Science.gov (United States)

    Zhu, Fengxiang; Pan, Zaifa; Hong, Chunlai; Wang, Weiping; Chen, Xiaoyang; Xue, Zhiyong; Yao, Yanlai

    2016-12-01

    Changes in volatile organic compound contents in compost samples during pig manure composting were studied using a headspace, solid-phase micro-extraction method (HS-SPME) followed by gas chromatography with mass spectrometric detection (GC/MS). Parameters affecting the SPME procedure were optimized as follows: the coating was carbon molecular sieve/polydimethylsiloxane (CAR/PDMS) fiber, the temperature was 60°C and the time was 30min. Under these conditions, 87 compounds were identified from 17 composting samples. Most of the volatile components could only be detected before day 22. However, benzenes, alkanes and alkenes increased and eventually stabilized after day 22. Phenol and acid substances, which are important factors for compost quality, were almost undetectable on day 39 in natural compost (NC) samples and on day 13 in maggot-treated compost (MC) samples. Our results indicate that the approach can be effectively used to determine the composting times by analysis of volatile substances in compost samples. An appropriate composting time not only ensures the quality of compost and reduces the loss of composting material but also reduces the generation of hazardous substances. The appropriate composting times for MC and NC were approximately 22days and 40days, respectively, during the summer in Zhejiang. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Tank 241-U-104 headspace gas and vapor characterization results from samples collected on July 16, 1996

    International Nuclear Information System (INIS)

    Pool, K.H.; Evans, J.C.; Hayes, J.C.; Mitroshkov, A.V.; Edwards, J.A.; Julya, J.L.; Thornton, B.M.; Fruchter, J.S.; Silvers, K.L.

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-U-104 (Tank U-104) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. No analytes were determined to be above the immediate notification limits specified by the sampling and analysis plan. None of the flammable constituents were present at concentrations above the analytical instrument detection limits. Total headspace flammability was estimated to be <0.108% of the lower flammability limit. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in a table. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0

  7. Development of a dynamic headspace solid-phase microextraction procedure coupled to GC-qMSD for evaluation the chemical profile in alcoholic beverages

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, F.; Caldeira, M. [Centro de Quimica da Madeira, Departamento de Quimica, Universidade da Madeira, Campus Universitario da Penteada, 9000-390 Funchal (Portugal); Camara, J.S. [Centro de Quimica da Madeira, Departamento de Quimica, Universidade da Madeira, Campus Universitario da Penteada, 9000-390 Funchal (Portugal)], E-mail: jsc@uma.pt

    2008-02-18

    In the present study, a simple and sensitive methodology based on dynamic headspace solid-phase microextraction (HS-SPME) followed by thermal desorption gas chromatography with quadrupole mass detection (GC-qMSD), was developed and optimized for the determination of volatile (VOCs) and semi-volatile (SVOCs) compounds from different alcoholic beverages: wine, beer and whisky. Key experimental factors influencing the equilibrium of the VOCs and SVOCs between the sample and the SPME fibre, as the type of fibre coating, extraction time and temperature, sample stirring and ionic strength, were optimized. The performance of five commercially available SPME fibres was evaluated and compared, namely polydimethylsiloxane (PDMS, 100 {mu}m); polyacrylate (PA, 85 {mu}m); polydimethylsiloxane/divinylbenzene (PDMS/DVB, 65 {mu}m); carboxen{sup TM}/polydimethylsiloxane (CAR/PDMS, 75 {mu}m) and the divinylbenzene/carboxen on polydimethylsiloxane (DVB/CAR/PDMS, 50/30 {mu}m) (StableFlex). An objective comparison among different alcoholic beverages has been established in terms of qualitative and semi-quantitative differences on volatile and semi-volatile compounds. These compounds belong to several chemical families, including higher alcohols, ethyl esters, fatty acids, higher alcohol acetates, isoamyl esters, carbonyl compounds, furanic compounds, terpenoids, C13-norisoprenoids and volatile phenols. The optimized extraction conditions and GC-qMSD, lead to the successful identification of 44 compounds in white wines, 64 in beers and 104 in whiskys. Some of these compounds were found in all of the examined beverage samples. The main components of the HS-SPME found in white wines were ethyl octanoate (46.9%), ethyl decanoate (30.3%), ethyl 9-decenoate (10.7%), ethyl hexanoate (3.1%), and isoamyl octanoate (2.7%). As for beers, the major compounds were isoamyl alcohol (11.5%), ethyl octanoate (9.1%), isoamyl acetate (8.2%), 2-ethyl-1-hexanol (5.9%), and octanoic acid (5.5%). Ethyl

  8. Development of a dynamic headspace solid-phase microextraction procedure coupled to GC-qMSD for evaluation the chemical profile in alcoholic beverages

    International Nuclear Information System (INIS)

    Rodrigues, F.; Caldeira, M.; Camara, J.S.

    2008-01-01

    In the present study, a simple and sensitive methodology based on dynamic headspace solid-phase microextraction (HS-SPME) followed by thermal desorption gas chromatography with quadrupole mass detection (GC-qMSD), was developed and optimized for the determination of volatile (VOCs) and semi-volatile (SVOCs) compounds from different alcoholic beverages: wine, beer and whisky. Key experimental factors influencing the equilibrium of the VOCs and SVOCs between the sample and the SPME fibre, as the type of fibre coating, extraction time and temperature, sample stirring and ionic strength, were optimized. The performance of five commercially available SPME fibres was evaluated and compared, namely polydimethylsiloxane (PDMS, 100 μm); polyacrylate (PA, 85 μm); polydimethylsiloxane/divinylbenzene (PDMS/DVB, 65 μm); carboxen TM /polydimethylsiloxane (CAR/PDMS, 75 μm) and the divinylbenzene/carboxen on polydimethylsiloxane (DVB/CAR/PDMS, 50/30 μm) (StableFlex). An objective comparison among different alcoholic beverages has been established in terms of qualitative and semi-quantitative differences on volatile and semi-volatile compounds. These compounds belong to several chemical families, including higher alcohols, ethyl esters, fatty acids, higher alcohol acetates, isoamyl esters, carbonyl compounds, furanic compounds, terpenoids, C13-norisoprenoids and volatile phenols. The optimized extraction conditions and GC-qMSD, lead to the successful identification of 44 compounds in white wines, 64 in beers and 104 in whiskys. Some of these compounds were found in all of the examined beverage samples. The main components of the HS-SPME found in white wines were ethyl octanoate (46.9%), ethyl decanoate (30.3%), ethyl 9-decenoate (10.7%), ethyl hexanoate (3.1%), and isoamyl octanoate (2.7%). As for beers, the major compounds were isoamyl alcohol (11.5%), ethyl octanoate (9.1%), isoamyl acetate (8.2%), 2-ethyl-1-hexanol (5.9%), and octanoic acid (5.5%). Ethyl decanoate (58

  9. 1H NMR and SPME-GC/MS study of hydrolysis, oxidation and other reactions occurring during in vitro digestion of non-oxidized and oxidized sunflower oil. Formation of hydroxy-octadecadienoates.

    Science.gov (United States)

    Nieva-Echevarría, Bárbara; Goicoechea, Encarnación; Manzanos, María J; Guillén, María D

    2017-01-01

    Both fresh and slightly oxidized sunflower oils, as models of omega-6 rich lipids, were submitted to in vitro gastrointestinal digestion and studied by 1 H NMR and SPME-GC/MS. Changes in lipolysis degree, lipid composition and oxidative level were studied by 1 H NMR. Three quantitative approaches were used and several equations were newly developed. In oxidized oil digestates slightly lower hydrolysis and a higher advance of oxidation took place during digestion. This latter was evidenced by a greater decrease of lipid unsaturation degree and enhanced generation of oxidation products (cis,trans-hydroperoxy-octadecadienoates, cis,trans- and trans,trans-hydroxy-octadecadienoates). For the first time, the generation of hydroxy-octadecadienoates during in vitro digestion is reported. Furthermore, SPME-GC/MS study of non-digested and digested samples headspaces confirmed that lipid oxidation occurred: abundances of volatile markers increased (including potentially toxic alpha,beta-unsaturated aldehydes), especially in oxidized oils digestates. Markers of Maillard-type and esterification reactions were also detected in the digestates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Nuevos desarrollos metodológicos en SPME

    OpenAIRE

    Ríos Acevedo, John Jairo

    2016-01-01

    La Microextracción en fase sólida (SPME) ha experimentado un rápido desarrollo desde su introducción hace más de 20 años teniendo un gran impacto sobre las prácticas de muestreo y preparación de muestra en áreas como análisis químico, bioanálisis, los alimentos y las ciencias ambientales. Sin embargo, en otras áreas como análisis clínico, ciencias farmacéuticas y médicas, se espera un crecimiento en sus aplicaciones. El objetivo fundamental de la presente investigación ha sido la implementaci...

  11. A comparison of sorptive extraction techniques coupled to a new quantitative, sensitive, high throughput GC-MS/MS method for methoxypyrazine analysis in wine.

    Science.gov (United States)

    Hjelmeland, Anna K; Wylie, Philip L; Ebeler, Susan E

    2016-02-01

    Methoxypyrazines are volatile compounds found in plants, microbes, and insects that have potent vegetal and earthy aromas. With sensory detection thresholds in the low ng L(-1) range, modest concentrations of these compounds can profoundly impact the aroma quality of foods and beverages, and high levels can lead to consumer rejection. The wine industry routinely analyzes the most prevalent methoxypyrazine, 2-isobutyl-3-methoxypyrazine (IBMP), to aid in harvest decisions, since concentrations decrease during berry ripening. In addition to IBMP, three other methoxypyrazines IPMP (2-isopropyl-3-methoxypyrazine), SBMP (2-sec-butyl-3-methoxypyrazine), and EMP (2-ethyl-3-methoxypyrazine) have been identified in grapes and/or wine and can impact aroma quality. Despite their routine analysis in the wine industry (mostly IBMP), accurate methoxypyrazine quantitation is hindered by two major challenges: sensitivity and resolution. With extremely low sensory detection thresholds (~8-15 ng L(-1) in wine for IBMP), highly sensitive analytical methods to quantify methoxypyrazines at trace levels are necessary. Here we were able to achieve resolution of IBMP as well as IPMP, EMP, and SBMP from co-eluting compounds using one-dimensional chromatography coupled to positive chemical ionization tandem mass spectrometry. Three extraction techniques HS-SPME (headspace-solid phase microextraction), SBSE (stirbar sorptive extraction), and HSSE (headspace sorptive extraction) were validated and compared. A 30 min extraction time was used for HS-SPME and SBSE extraction techniques, while 120 min was necessary to achieve sufficient sensitivity for HSSE extractions. All extraction methods have limits of quantitation (LOQ) at or below 1 ng L(-1) for all four methoxypyrazines analyzed, i.e., LOQ's at or below reported sensory detection limits in wine. The method is high throughput, with resolution of all compounds possible with a relatively rapid 27 min GC oven program. Copyright © 2015

  12. Rapid determination of the volatile components in tobacco by ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction with gas chromatography-mass spectrometry.

    Science.gov (United States)

    Yang, Yanqin; Chu, Guohai; Zhou, Guojun; Jiang, Jian; Yuan, Kailong; Pan, Yuanjiang; Song, Zhiyu; Li, Zuguang; Xia, Qian; Lu, Xinbo; Xiao, Weiqiang

    2016-03-01

    An ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction was first employed to determine the volatile components in tobacco samples. The method combined the advantages of ultrasound, microwave, and headspace solid-phase microextraction. The extraction, separation, and enrichment were performed in a single step, which could greatly simplify the operation and reduce the whole pretreatment time. In the developed method, several experimental parameters, such as fiber type, ultrasound power, and irradiation time, were optimized to improve sampling efficiency. Under the optimal conditions, there were 37, 36, 34, and 36 components identified in tobacco from Guizhou, Hunan, Yunnan, and Zimbabwe, respectively, including esters, heterocycles, alkanes, ketones, terpenoids, acids, phenols, and alcohols. The compound types were roughly the same while the contents were varied from different origins due to the disparity of their growing conditions, such as soil, water, and climate. In addition, the ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction method was compared with the microwave-assisted extraction coupled to headspace solid-phase microextraction and headspace solid-phase microextraction methods. More types of volatile components were obtained by using the ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction method, moreover, the contents were high. The results indicated that the ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction technique was a simple, time-saving and highly efficient approach, which was especially suitable for analysis of the volatile components in tobacco. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Classification of bacteria by simultaneous methylation-solid phase microextraction and gas chromatography/mass spectrometry analysis of fatty acid methyl esters.

    Science.gov (United States)

    Lu, Yao; Harrington, Peter B

    2010-08-01

    Direct methylation and solid-phase microextraction (SPME) were used as a sample preparation technique for classification of bacteria based on fatty acid methyl ester (FAME) profiles. Methanolic tetramethylammonium hydroxide was applied as a dual-function reagent to saponify and derivatize whole-cell bacterial fatty acids into FAMEs in one step, and SPME was used to extract the bacterial FAMEs from the headspace. Compared with traditional alkaline saponification and sample preparation using liquid-liquid extraction, the method presented in this work avoids using comparatively large amounts of inorganic and organic solvents and greatly decreases the sample preparation time as well. Characteristic gas chromatography/mass spectrometry (GC/MS) of FAME profiles was achieved for six bacterial species. The difference between Gram-positive and Gram-negative bacteria was clearly visualized with the application of principal component analysis of the GC/MS data of bacterial FAMEs. A cross-validation study using ten bootstrap Latin partitions and the fuzzy rule building expert system demonstrated 87 +/- 3% correct classification efficiency.

  14. Determination of semi-volatile additives in wines using SPME and GC-MS.

    Science.gov (United States)

    Sagandykova, Gulyaim N; Alimzhanova, Mereke B; Nurzhanova, Yenglik T; Kenessov, Bulat

    2017-04-01

    Parameters of headspace solid-phase microextraction, such as fiber coating (85μm CAR/PDMS), extraction time (2min for white and 3min for red wines), temperature (85°C), pre-incubation time (15min) were optimized for identification and quantification of semi-volatile additives (propylene glycol, sorbic and benzoic acids) in wines. To overcome problems in their determination, an evaporation of the wine matrix was performed. Using the optimized method, screening of 25 wine samples was performed, and the presence of propylene glycol, sorbic and benzoic acids was found in 22, 20 and 6 samples, respectively. Analysis of different wines using a standard addition approach showed good linearity in concentration ranges 0-250, 0-125, and 0-250mg/L for propylene glycol, sorbic and benzoic acids, respectively. The proposed method can be recommended for quality control of wine and disclosing adulterated samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Headspace vapor characterization of Hanford Waste Tank 241-S-112: Results from samples collected on July 11, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Clauss, T.W.; Pool, K.H.; Evans, J.C.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage Tank 241-S-112 (Tank S-112) at the Hanford. Pacific Northwest National Laboratory (PNNL) is contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5044. Samples were collected by WHC on July 11, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  16. Headspace vapor characterization of Hanford Waste Tank SX-102: Results from samples collected on July 19, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    McVeety, B.D.; Evans, J.C.; Clauss, T.W.; Pool, K.H.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-SX-102 (Tank SX-102) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed under the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5046. Samples were collected by WHC on July 19, 1995, using the vapor sampling system (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  17. Headspace vapor characterization of Hanford Waste Tank 241-T-110: Results from samples collected on August 31, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    McVeety, B.D.; Thomas, B.L.; Evans, J.C.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-T-110 (Tank T-110) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5056. Samples were collected by WHC on August 31, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  18. Headspace vapor characterization of Hanford Waste Tank 241-TX-111: Results from samples collected on October 12, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Pool, K.H.; Clauss, T.W.; Evans, J.C.

    1996-06-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-TX-111 (Tank TX-111) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5069. Samples were collected by WHC on October 12, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  19. Headspace vapor characterization of Hanford Waste Tank AX-103: Results from samples collected on June 21, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Ligotke, M.W.; Pool, K.H.; Clauss, T.W.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-AX-103 (Tank AX-103) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5029. Samples were collected by WHC on June 21, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  20. Headspace vapor characterization of Hanford Waste Tank AX-101: Results from samples collected on June 15, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Pool, K.H.; Clauss, T.W.; Evans, J.C.; McVeety, B.D.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-AX-101 (Tank AX-101) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) under the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5028. Samples were collected by WHC on June 15, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  1. Headspace vapor characterization of Hanford Waste Tank 241-SX-109: Results from samples collected on August 1, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Pool, K.H.; Clauss, T.W.; Evans, J.C.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-SX-109 (Tank SX-109) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5048. Samples were collected by WHC on August 1, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  2. Headspace vapor characterization of Hanford Waste Tank 241-SX-104: Results from samples collected on July 25, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Thomas, B.L.; Clauss, T.W.; Evans, J.C.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-SX-104 (Tank SX-104) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5049. Samples were collected by WHC on July 25, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  3. Headspace vapor characterization of Hanford Waste Tank 241-SX-105: Results from samples collected on July 26, 1995. Tank Vapor Characterization Project

    International Nuclear Information System (INIS)

    Pool, K.H.; Clauss, T.W.; Evans, J.C.

    1996-05-01

    This report describes the results of vapor samples taken from the headspace of waste storage tank 241-SX-105 (Tank SX-105) at the Hanford Site in Washington State. Pacific Northwest National Laboratory (PNNL) contracted with Westinghouse Hanford Company (WHC) to provide sampling devices and analyze samples for inorganic and organic analytes collected from the tank headspace and ambient air near the tank. The analytical work was performed by the PNNL Vapor Analytical Laboratory (VAL) by the Tank Vapor Characterization Project. Work performed was based on a sample and analysis plan (SAP) prepared by WHC. The SAP provided job-specific instructions for samples, analyses, and reporting. The SAP for this sample job was open-quotes Vapor Sampling and Analysis Planclose quotes, and the sample job was designated S5047. Samples were collected by WHC on July 26, 1995, using the Vapor Sampling System (VSS), a truck-based sampling method using a heated probe inserted into the tank headspace

  4. Rapid evaluation technique to differentiate mushroom disease-related moulds by detecting microbial volatile organic compounds using HS-SPME-GC-MS.

    Science.gov (United States)

    Radványi, Dalma; Gere, Attila; Jókai, Zsuzsa; Fodor, Péter

    2015-01-01

    Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to analyse microbial volatile organic compounds (MVOCs) of mushroom disease-related microorganisms. Mycogone perniciosa, Lecanicillum fungicola var. fungicola, and Trichoderma aggressivum f. europaeum species, which are typically harmful in mushroom cultivation, were examined, and Agaricus bisporus (bisporic button mushroom) was also examined as a control. For internal standard, a mixture of alkanes was used; these were introduced as the memory effect of primed septa in the vial seal. Several different marker compounds were found in each sample, which enabled us to distinguish the different moulds and the mushroom mycelium from each other. Monitoring of marker compounds enabled us to investigate the behaviour of moulds. The records of the temporal pattern changes were used to produce partial least squares regression (PLS-R) models that enabled determination of the exact time of contamination (the infection time of the media). Using these evaluation techniques, the presence of mushroom disease-related fungi can be easily detected and monitored via their emitted MVOCs.

  5. Study of aroma formation and transformation during the manufacturing process of Biluochun green tea in Yunnan Province by HS-SPME and GC-MS.

    Science.gov (United States)

    Wang, Chen; Lv, Shidong; Wu, Yuanshuang; Lian, Ming; Gao, Xuemei; Meng, Qingxiong

    2016-10-01

    Biluochun is a typical non-fermented tea and is also famous for its unique aroma in China. Few studies have been performed to evaluate the effect of the manufacturing process on the formation and content of its aroma. The volatile components were extracted at different manufacturing process steps of Biluochun green tea using fully automated headspace solid-phase microextraction (HS-SPME) and further characterised by gas chromatography-mass spectrometry (GC-MS). Among 67 volatile components collected, the fractions of linalool oxides, β-ionone, phenylacetaldehyde, aldehydes, ketones, and nitrogen compounds were increased while alcohols and hydrocarbons declined during the manufacturing process. The aroma compounds decreased the most during the drying steps. We identified a number of significantly changed components that can be used as markers and quality control during the producing process of Biluochun. The drying step played a major role in the aroma formation of green tea products and should be the most important step for quality control. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. A sensitive method using SPME pre-concentration for the quantification of aromatic amines in indoor air.

    Science.gov (United States)

    Lucaire, Vincent; Schwartz, Jean-Jacques; Delhomme, Olivier; Ocampo-Torres, Ruben; Millet, Maurice

    2018-03-01

    Monitoring the levels of aliphatic and aromatic amines (AA) in indoor air is important to protect human health because of exposure to these compounds through diet and inhalation. A sampling and analytical method using XAD-2 cartridges and gas chromatography coupled to mass spectrometry used for assessing 25 AA in different smoking and non-smoking indoor environment was developed. After sampling and delivering 1 m 3 of air (6-8 h sampling), an adsorbent was ultrasonically extracted with acetonitrile, concentrated to 1 mL and diluted in 25 mL of water (pH = 9; 5% NaCl), and then extracted for 40 min at 80 °C using a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber and injected in a GC/MS system. With this method, 22 of the 25 AA can be analyzed with detection limits up to five times lower than that of classic liquid injection. Benzylamine, 3-aminophenol, and 4-aminophenol were not detected with the solid-phase micro-extraction (SPME) method. It can be assumed that aminophenols required a derivatization step for their analysis by GC as these molecules were not detected regardless of the injection mode used. Graphical abstract Analysis of aromatic amines in indoor air by SPME-GC/MS.

  7. Análise de pesticidas organoclorados em água usando a microextração em fase sólida por headspace com cromatografia gasosa e espectrometria de massas

    Directory of Open Access Journals (Sweden)

    Crislaine Batista Prates

    2011-01-01

    Full Text Available A method based on headspace - solid phase microextraction coupled with gas chromatography - mass spectrometry was validated for the quantitative determination of 18 organochlorine pesticides in water. For the extraction conditioning some parameters as the best type of coating fiber, time and temperature of extraction, pH and ionic strength were evaluated. The method HS-SPME/GC-MS/MS showed linear coefficient above 0.9948. The repeatability of the measurements were lower than 7.6%. Relative recoveries were between 88 and 110%. Limits of detection from 0.5 x 10-3 to 1.0 mg L-1 were obtained. A total of 31 samples were analyzed and 16 presented from 1 to 5 pesticides.

  8. Partitioning of the pesticide trifluralin between dissolved organic matter and water using automated SPME-GC/MS

    KAUST Repository

    Caupos, Emilie

    2014-10-04

    Solid-phase microextraction (SPME) was used to determine the equilibrium association constant for a pesticide, trifluralin (TFR), with dissolved organic matter (DOM). After optimization of the SPME method for the analysis of TFR, partition coefficients (K DOM) with three different sources of DOM were determined in buffered solutions at pH 7. Commercial humic acids and DOM fractions isolated from two surface waters were used. The values of log K DOMvaried from 4.3 to 5.8, depending on the nature of the organic material. A good correlation was established between log K DOMand DOM properties (as measured with the H/O atomic ratio and UV absorbance), in agreement with literature data. This is consistent with the effect of polarity and aromaticity for governing DOM-pollutant associations, regardless of the origin of DOM. This association phenomenon is relevant to better understand the behavior of pesticides in the environment since it controls part of pesticide leaching and fate in aquatic systems.

  9. Rapid identification of pork for halal authentication using the electronic nose and gas chromatography mass spectrometer with headspace analyzer.

    Science.gov (United States)

    Nurjuliana, M; Che Man, Y B; Mat Hashim, D; Mohamed, A K S

    2011-08-01

    The volatile compounds of pork, other meats and meat products were studied using an electronic nose and gas chromatography mass spectrometer with headspace analyzer (GCMS-HS) for halal verification. The zNose™ was successfully employed for identification and differentiation of pork and pork sausages from beef, mutton and chicken meats and sausages which were achieved using a visual odor pattern called VaporPrint™, derived from the frequency of the surface acoustic wave (SAW) detector of the electronic nose. GCMS-HS was employed to separate and analyze the headspace gasses from samples into peaks corresponding to individual compounds for the purpose of identification. Principal component analysis (PCA) was applied for data interpretation. Analysis by PCA was able to cluster and discriminate pork from other types of meats and sausages. It was shown that PCA could provide a good separation of the samples with 67% of the total variance accounted by PC1. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Selective molecularly imprinted polymer combined with restricted access material for in-tube SPME/UHPLC-MS/MS of parabens in breast milk samples.

    Science.gov (United States)

    Souza, Israel D; Melo, Lidervan P; Jardim, Isabel C S F; Monteiro, Juliana C S; Nakano, Ana Marcia S; Queiroz, Maria Eugênia C

    2016-08-17

    A new molecularly imprinted polymer modified with restricted access material (a hydrophilic external layer), (MIP-RAM) was synthesized via polymerization in situ in an open fused silica capillary. This stationary phase was used as sorbent for in-tube solid phase microextraction (in-tube SPME) to determine parabens in breast milk samples by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Scanning electron micrographs (SEM) illustrate MIP surface modification after glycerol dimethacrylate (hydrophilic monomer) incorporation. The interaction between parabens and MIP-RAM was investigated by Fourier-transform infrared (FTIR) spectroscopy. The Scatchard plot for MIP-RAM presented two linear parts with different slopes, illustrating binding sites with high- and low-affinity. Endogenous compounds exclusion from the MIP-RAM capillary was demonstrated by in-tube SPME/LC-UV assays carried out with blank milk samples. The in-tube SPME/UHPLC-MS/MS method presented linear range from 10 ng mL(-1) (LLOQ) to 400 ng mL(-1) with coefficients of determination higher than 0.99, inter-assay precision with coefficient of variation (CV) values ranging from 2 to 15%, and inter-assay accuracy with relative standard deviation (RSD) values ranging from -1% to 19%. Analytical validation parameters attested that in-tube SPME/UHPLC-MS/MS is an appropriate method to determine parabens in human milk samples to assess human exposure to these compounds. Analysis of breast milk samples from lactating women demonstrated that the proposed method is effective. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Determination of volatile organic compounds (VOCs) using tedlar bag/solid-phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS) in ambient and workplace air

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Hwan; Lee, Dai Woon [Yonsei Univ., Seoul (Korea, Republic of); Hwang, Seung Man; Heo, Gwi Suk [Korea Research Institute of Standards and Science, Taejon (Korea, Republic of)

    2002-03-01

    SPME techniques have proven to be very useful tools in the analysis of wide VOCs in the air. In this study, we estimated VOCs in ambient and workplace air using a Tedlar ba/SPME/GC/MS system. The calibration curve was set to be linear over the range of 1-30 ppbv. The detection limits ranged from 10 pptv 0.93 ppbv for all VOCs. Reproducibility of TO-14 target gas mixtures by SPME/GC/MS averaged at 8.8 R.S.D (%). Air toxic VOCs (hazardous air pollutants, HAPs) containing a total of forty halohydrocarbons, aromatics, and haloaro-matic carbons could be analyzed with significant accuracy, detection limit and linearity at low ppbv level. Only reactive VOCs with low molecular weight, such as chloromethane, vinylchloride, ethylchloride and 1,2-dichloro-ethane, yielded relatively poor results using this technique. In ambient air samples, ten VOCs were identified and quantified after external calibration. VOC concentration in ambient and workplace air ranged from 0.04 to 1.85 ppbv. The overall process was successfully applied to identify and quantify VOCs in ambient/workplace air.

  12. Determination of volatile organic compounds (VOCs) using tedlar bag/solid-phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS) in ambient and workplace air

    International Nuclear Information System (INIS)

    Lee, Jae Hwan; Lee, Dai Woon; Hwang, Seung Man; Heo, Gwi Suk

    2002-01-01

    SPME techniques have proven to be very useful tools in the analysis of wide VOCs in the air. In this study, we estimated VOCs in ambient and workplace air using a Tedlar ba/SPME/GC/MS system. The calibration curve was set to be linear over the range of 1-30 ppbv. The detection limits ranged from 10 pptv 0.93 ppbv for all VOCs. Reproducibility of TO-14 target gas mixtures by SPME/GC/MS averaged at 8.8 R.S.D (%). Air toxic VOCs (hazardous air pollutants, HAPs) containing a total of forty halohydrocarbons, aromatics, and haloaro-matic carbons could be analyzed with significant accuracy, detection limit and linearity at low ppbv level. Only reactive VOCs with low molecular weight, such as chloromethane, vinylchloride, ethylchloride and 1,2-dichloro-ethane, yielded relatively poor results using this technique. In ambient air samples, ten VOCs were identified and quantified after external calibration. VOC concentration in ambient and workplace air ranged from 0.04 to 1.85 ppbv. The overall process was successfully applied to identify and quantify VOCs in ambient/workplace air

  13. Determination of volatile polycyclic aromatic hydrocarbons in waters using headspace solid-phase microextraction with a benzyl-functionalized crosslinked polymeric ionic liquid coating.

    Science.gov (United States)

    Merdivan, Melek; Pino, Verónica; Anderson, Jared L

    2017-08-01

    A benzyl-functionalized crosslinked polymeric ionic liquid (PIL), produced through the co-polymerization of the 1-vinylbenzyl-3-hexadecylimidazolium bis[(trifluoromethyl)sulfonyl]imide (VBHDIM-NTf 2 ) ionic liquid (IL) monomer and 1,12-di(3-vinylbenzylimidazolium)dodecane bis[(trifluoromethyl)sulfonyl]imide ((DVBIM) 2 C 12- 2NTf 2 ) IL crosslinker, was successfully used as a sorbent coating in headspace solid-phase microextraction (SPME) coupled to gas chromatography (GC) with flame-ionization detection (FID) to determine seven volatile polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Optimum extraction conditions for the PAHs when using the novel sorbent include an extraction temperature of 50°C, an ionic strength content adjusted with 30% (w/v) NaCl in the aqueous sample, and an extraction time of 60 min. The extraction performance of the crosslinked PIL fiber was compared to the SPME commercial coating polydimethylsiloxane fiber. The calibration ranges of the studied PAHs were linear in the range of 0.02-20 µg L -1 for the crosslinked PIL fiber. The accuracy of the proposed method was demonstrated by examining the spiked recoveries of seven PAHs which produced values ranging from 67.2% to 130% (for river- and seawater samples), and precision values lower than 9.4% for a spiked level of 1 µg L -1 , and detection limits between 0.01 and 0.04 µg L -1 , which supports the sensitivity of the method using GC-FID.

  14. Simple determination of hydrazine in waste water by headspace solid-phase micro extraction and gas chromatography-tandem mass spectrometry after derivatization with trifluoro pentanedione.

    Science.gov (United States)

    Oh, Jin-Aa; Shin, Ho-Sang

    2017-01-15

    A headspace solid-phase micro extraction (HS-SPME) and gas chromatography-tandem mass spectrometric (GC-MS/MS) method is described to detect hydrazine after derivatization with 1,1,1-trifluoro-2,4-pentanedione (1,1,1-TFPD) to 3-methyl-5-(trifluoromethyl) pyrazole in industrial waste water. The following optimal HS-SPME conditions were used: 85 μm-carboxen-polydimethylsiloxane fibre, 100 mg L -1 TFPD, saturated NaCl, an extraction/derivatization temperature of 80 °C, a heating time of 40 min, and a pH of 9.5. Under the established conditions, the detection and quantification limits were 0.002 μg L -1 and 0.007 μg L -1  by using 5 mL of waste water and the intra- and inter-day relative standard deviations were less than 10.2% at concentrations of 0.02 and 0.1 μg L -1 . The calibration curve showed good linearity, with r 2  = 0.998; the accuracy was in the range of 98.0-103%; and the precision of the assay was less than 10.2% in industrial waste water. Hydrazine was detected over a concentration range of 0.011-0.074 μg L -1 in 5 of 20 waste water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Headspace vapor characterization of Hanford waste tank 241-B-107: Results from samples collected on 7/23/96

    International Nuclear Information System (INIS)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-B-107 (Tank B-107) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwestern National Laboratory (PNNL). A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in a table. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in the same table. Detailed descriptions of the analytical results appear in the appendices

  16. Headspace vapor characterization of Hanford waste tank 241-S-106: Results from samples collected on 06/13/96

    International Nuclear Information System (INIS)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-S-106 (Tank S-106) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in a table. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in the same table. Detailed descriptions of the analytical results appear in the appendices

  17. Headspace vapor characterization of Hanford waste Tank 241-C-201: Results from samples collected on 06/19/96

    International Nuclear Information System (INIS)

    Thomas, B.L.; Evans, J.C.; Pool, K.H.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-C-201 (Tank C-201) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, on sample volumes provided by WHC. A summary, of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in a table. Detailed descriptions of the analytical results appear in the appendices

  18. JV Task 92 - Alcoa/Retec SFE and SPME

    Energy Technology Data Exchange (ETDEWEB)

    Steven Hawthorne

    2009-02-15

    This report summarizes the work performed by the Energy & Environmental Research Center (EERC) under the U.S. Department of Energy Jointly Sponsored Research Program JV Task 92, which is a continuation of JV9. Successful studies performed in 1999 through the end of 2008 demonstrated the potential for using selective supercritical fluid extraction (SFE) and a solid-phase microextraction (SPME) method for measuring sediment pore water polycyclic aromatic hydrocarbons (PAHs) to mimic the bioavailability of PAHs from manufactured gas plant and aluminum smelter soils and sediments both in freshwater and saltwater locations. The studies that the EERC has performed with the commercial partners have continued to generate increased interest in both the regulatory communities and in the industries that have historically produced or utilized coal tar products. Both ASTM International and the U.S. Environmental Protection Agency (EPA) have accepted the pore water method developed at the EERC as standard methods. The studies have demonstrated the effectiveness of our techniques in predicting bioavailability of PAHs from ca. 250 impacted and background field sediments and soils. The field demonstrations from the final years of the project continued to build the foundation data for acceptance of our methods by the regulatory communities. The JV92 studies provide the single largest database in the world that includes measures of PAH bioavailability along with biological end points. These studies clearly demonstrated that present regulatory paradigms based on equilibrium partitioning greatly overpredict bioavailability. These investigations also laid the foundation for present (non-JV) studies being applied to PAHs and polychlorinated biphenyls (PCBs) at EPA Superfund sites, investigations into PAH and PCB bioavailability at U.S Department of Defense sites, and the application of the techniques to investigating the bioavailability of chlorinated dioxins and furans from impacted

  19. Determination of volatile organic compounds in water by headspace solid-phase microextraction gas chromatography coupled to tandem mass spectrometry with triple quadrupole analyzer

    International Nuclear Information System (INIS)

    Cervera, M.I.; Beltran, J.; Lopez, F.J.; Hernandez, F.

    2011-01-01

    Highlights: → Employing a statistical optimization improves results reducing experiments. → Use of MS (QqQ) allows high sensitivity determination and improves identification capabilities. → Using Q/q intensity ratios is a powerful tool to ensure compound identification. → HS SPME GC-MS/MS method allows determination of VOCs in complex matrix water samples. - Abstract: In the present work, a rapid method with little sample handling has been developed for determination of 23 selected volatile organic compounds in environmental and wastewater samples. The method is based on headspace solid-phase microextraction (SPME) followed by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) determination using triple quadrupole analyzer (QqQ) in electron ionization mode. The best conditions for extraction were optimised with a factorial design taking into account the interaction between different parameters and not only individual effects of variables. In the optimized procedure, 4 mL of water sample were extracted using a 10 mL vial and adding 0.4 g NaCl (final NaCl content of 10%). An SPME extraction with carboxen/polydimethylsiloxane 75 μm fiber for 30 min at 50 deg. C (with 5 min of previous equilibration time) with magnetic stirring was applied. Chromatographic determination was carried out by GC-MS/MS working in Selected Reaction Monitoring (SRM) mode. For most analytes, two MS/MS transitions were acquired, although for a few compounds it was difficult to obtain characteristic abundant fragments. In those cases, a pseudo selected reaction monitoring (pseudo-SRM) with three ions was used instead. The intensity ratio between quantitation (Q) and confirmation (q) signals was used as a confirmatory parameter. The method was validated by means of recovery experiments (n = 6) spiking mineral water samples at three concentration levels (0.1, 5 and 50 μg L -1 ). Recoveries between 70% and 120% were generally obtained with relative standard deviations (RSDs

  20. Determination of volatile organic compounds in water by headspace solid-phase microextraction gas chromatography coupled to tandem mass spectrometry with triple quadrupole analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Cervera, M.I. [Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellon (Spain); Beltran, J., E-mail: joaquim.beltran@uji.es [Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellon (Spain); Lopez, F.J.; Hernandez, F. [Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellon (Spain)

    2011-10-17

    Highlights: {yields} Employing a statistical optimization improves results reducing experiments. {yields} Use of MS (QqQ) allows high sensitivity determination and improves identification capabilities. {yields} Using Q/q intensity ratios is a powerful tool to ensure compound identification. {yields} HS SPME GC-MS/MS method allows determination of VOCs in complex matrix water samples. - Abstract: In the present work, a rapid method with little sample handling has been developed for determination of 23 selected volatile organic compounds in environmental and wastewater samples. The method is based on headspace solid-phase microextraction (SPME) followed by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) determination using triple quadrupole analyzer (QqQ) in electron ionization mode. The best conditions for extraction were optimised with a factorial design taking into account the interaction between different parameters and not only individual effects of variables. In the optimized procedure, 4 mL of water sample were extracted using a 10 mL vial and adding 0.4 g NaCl (final NaCl content of 10%). An SPME extraction with carboxen/polydimethylsiloxane 75 {mu}m fiber for 30 min at 50 deg. C (with 5 min of previous equilibration time) with magnetic stirring was applied. Chromatographic determination was carried out by GC-MS/MS working in Selected Reaction Monitoring (SRM) mode. For most analytes, two MS/MS transitions were acquired, although for a few compounds it was difficult to obtain characteristic abundant fragments. In those cases, a pseudo selected reaction monitoring (pseudo-SRM) with three ions was used instead. The intensity ratio between quantitation (Q) and confirmation (q) signals was used as a confirmatory parameter. The method was validated by means of recovery experiments (n = 6) spiking mineral water samples at three concentration levels (0.1, 5 and 50 {mu}g L{sup -1}). Recoveries between 70% and 120% were generally obtained with

  1. Characterization and classification of pequi trees (Caryocar brasiliense Camb. based on the profile of volatile constituents using headspace solid-phase microextraction - gas chromatography - mass spectrometry and multivariate analysis Caracterização e classificação de pequizeiros (Caryocar brasiliense Camb. baseadas no perfil de constituintes voláteis usando microextração em fase sólida no modo headspace - cromatografia a gás - espectrometria de massas e análise multivariada

    Directory of Open Access Journals (Sweden)

    Renata França Cassimiro Belo

    2013-02-01

    Full Text Available In order to determine the variability of pequi tree (Caryocar brasiliense Camb. populations, volatile compounds from fruits of eighteen trees representing five populations were extracted by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. Seventy-seven compounds were identified, including esters, hydrocarbons, terpenoids, ketones, lactones, and alcohols. Several compounds had not been previously reported in the pequi fruit. The amount of total volatile compounds and the individual compound contents varied between plants. The volatile profile enabled the differentiation of all of the eighteen plants, indicating that there is a characteristic profile in terms of their origin. The use of Principal Component Analysis and Cluster Analysis enabled the establishment of markers (dendrolasin, ethyl octanoate, ethyl 2-octenoate and β-cis-ocimene that discriminated among the pequi trees. According to the Cluster Analysis, the plants were classified into three main clusters, and four other plants showed a tendency to isolation. The results from multivariate analysis did not always group plants from the same population together, indicating that there is greater variability within the populations than between pequi tree populations.A fim de determinar a variabilidade de populações de pequizeiro (Caryocar brasiliense Camb., compostos voláteis de frutos de dezoito árvores representando cinco populações foram extraídos por microextração em fase sólida no modo headspace e analisados por cromatografia a gás acoplada à espectrometria de massas. Setenta e sete compostos foram identificados, incluindo ésteres, hidrocarbonetos, terpenoides, cetonas, lactonas e álcoois. Vários compostos não haviam sido encontrados anteriormente no fruto. A quantidade total e a composição de voláteis variaram entre as plantas. O perfil volátil permitiu a diferenciação de todas as dezoito plantas, indicando que há um

  2. Quantification of liquid products from the electroreduction of CO2 and CO using static headspace-gas chromatography and nuclear magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Bertheussen, Erlend; Abghoui, Younes; Jovanov, Zarko P.

    2017-01-01

    Static headspace-gas chromatography (HS-GC) useful for ex-situ liquid product analysis. Could complement high-performance liquid chromatography and NMR spectroscopy. Particularly high sensitivity towards compounds with high vapor pressure. Detection limits below 0.5μM were shown for acetaldehyde...

  3. Fingerprint of volatiles from plant extracts based on SPME-GC-MS

    Directory of Open Access Journals (Sweden)

    Ezequias P. Siqueira

    Full Text Available The Laboratory of Chemistry of Natural Products has an ex situ collection of extracts from organisms of the biodiversity aiming at bioprospecting. Nowadays the collection has about 4000 extracts from 1000 different species. Extracts are used to identify new bioactive compounds that could be useful for developing new drugs against neglected diseases like leishmaniosis, Chagas disease, malaria and tuberculosis. After biologic assays, the bioactive extracts need to be prepared in larger quantity to allow isolation and characterization of the bioactive component. At this time, it is important to not only confirm the bioactivity of new extract but also check if its composition is similar to the old one. It was evaluated the ability of Solid Phase Microextraction and Gas Chromatography-Mass Spectrometry analysis (SPME-GC-MS. It was used the AMDIS (Automatic Mass Spectral Deconvolution and Identification System software as tools to collect and to compare the chromatographic profiles of each extract (fingerprint. Forty six samples were analyzed, it was possible to infer from the composition of each sample and common compounds. Nine groups of samples, collected at different time, were analyzed and seasonal modifications between then could be elucidated. The results showed that this methodology can be used to monitor the composition of extracts, allowing to monitor chemical changes that may occur during storage periods and to investigate the occurrence of a determined component in different extracts.

  4. Evaluation of peroxidative stress of cancer cells in vitro by real-time quantification of volatile aldehydes in culture headspace.

    Science.gov (United States)

    Shestivska, Violetta; Rutter, Abigail V; Sulé-Suso, Josep; Smith, David; Španěl, Patrik

    2017-08-30

    Peroxidation of lipids in cellular membranes results in the release of volatile organic compounds (VOCs), including saturated aldehydes. The real-time quantification of trace VOCs produced by cancer cells during peroxidative stress presents a new challenge to non-invasive clinical diagnostics, which as described here, we have met with some success. A combination of selected ion flow tube mass spectrometry (SIFT-MS), a technique that allows rapid, reliable quantification of VOCs in humid air and liquid headspace, and electrochemistry to generate reactive oxygen species (ROS) in vitro has been used. Thus, VOCs present in the headspace of CALU-1 cancer cell line cultures exposed to ROS have been monitored and quantified in real time using SIFT-MS. The CALU-1 lung cancer cells were cultured in 3D collagen to mimic in vivo tissue. Real-time SIFT-MS analyses focused on the volatile aldehydes: propanal, butanal, pentanal, hexanal, heptanal and malondialdehyde (propanedial), that are expected to be products of cellular membrane peroxidation. All six aldehydes were identified in the culture headspace, each reaching peak concentrations during the time of exposure to ROS and eventually reducing as the reactants were depleted in the culture. Pentanal and hexanal were the most abundant, reaching concentrations of a few hundred parts-per-billion by volume, ppbv, in the culture headspace. The results of these experiments demonstrate that peroxidation of cancer cells in vitro can be monitored and evaluated by direct real-time analysis of the volatile aldehydes produced. The combination of adopted methodology potentially has value for the study of other types of VOCs that may be produced by cellular damage. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Rapid determination of methanol in black liquors by full evaporation headspace gas chromatography.

    Science.gov (United States)

    Li, Hailong; Zhan, Huaiyu; Fu, Shiyu; Liu, Mengru; Chai, Xin-Sheng

    2007-12-14

    This paper reported a full evaporation headspace gas chromatographic (GC) technique for determination of methanol content in black liquors (pulping spent liquor). In this method, a very small volume (10-20 microL) of liquor sample is introduced into a headspace sample vial (20 mL) and heated up to a temperature of 105 degrees C. A near-complete mass transfer of methanol from the liquid phase to vapor phase (headspace), i.e., a full evaporation, can be achieved within 3 min. The methanol in the headspace of the vial is then measured by GC. The present method is simple, rapid and accurate.

  6. Phytoscreening for chlorinated solvents using rapid in vitro SPME sampling: Application to urban plume in Verl, Germany

    Science.gov (United States)

    Limmer, M.A.; Balouet, J.-C.; Karg, F.; Vroblesky, D.A.; Burken, J.G.

    2011-01-01

    Rapid detection and delineation of contaminants in urban settings is critically important in protecting human health. Cores from trees growing above a plume of contaminated groundwater in Verl, Germany, were collected in 1 day, with subsequent analysis and plume mapping completed over several days. Solid-phase microextraction (SPME) analysis was applied to detect tetrachloroethene (PCE) and trichloroethene (TCE) to below nanogram/liter levels in the transpiration stream of the trees. The tree core concentrations showed a clear areal correlation to the distribution of PCE and TCE in the groundwater. Concentrations in tree cores were lower than the underlying groundwater, as anticipated; however, the tree core water retained the PCE:TCE signature of the underlying groundwater in the urban, populated area. The PCE:TCE ratio can indicate areas of differing degradation activity. Therefore, the phytoscreening analysis was capable not only of mapping the spatial distribution of groundwater contamination but also of delineating zones of potentially differing contaminant sources and degradation. The simplicity of tree coring and the ability to collect a large number of samples in a day with minimal disruption or property damage in the urban setting demonstrates that phytoscreening can be a powerful tool for gaining reconnaissance-level information on groundwater contaminated by chlorinated solvents. The use of SPME decreases the detection level considerably and increases the sensitivity of phytoscreening as an assessment, monitoring, and phytoforensic tool. With rapid, inexpensive, and noninvasive methods of detecting and delineating contaminants underlying homes, as in this case, human health can be better protected through screening of broader areas and with far faster response times. ?? 2011 American Chemical Society.

  7. Headspace screening: A novel approach for fast quality assessment of the essential oil from culinary sage.

    Science.gov (United States)

    Cvetkovikj, Ivana; Stefkov, Gjoshe; Acevska, Jelena; Karapandzova, Marija; Dimitrovska, Aneta; Kulevanova, Svetlana

    2016-07-01

    Quality assessment of essential oil (EO) from culinary sage (Salvia officinalis L., Lamiaceae) is limited by the long pharmacopoeial procedure. The aim of this study was to employ headspace (HS) sampling in the quality assessment of sage EO. Different populations (30) of culinary sage were assessed using GC/FID/MS analysis of the hydrodistilled EO (pharmacopoeial method) and HS sampling directly from leaves. Compound profiles from both procedures were evaluated according to ISO 9909 and GDC standards for sage EO quality, revealing compliance for only 10 populations. Factors to convert HS values, for the target ISO and GDC components, into theoretical EO values were calculated. Statistical analysis revealed a significant relationship between HS and EO values for seven target components. Consequently, HS sampling could be used as a complementary extraction technique for rapid screening in quality assessment of sage EOs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Extração em fase sólida (SPE e micro extração em fase sólida (SPME de piretróides em água Solid-phase extraction (SPE and solid-phase microextraction of pyrethroids in water

    Directory of Open Access Journals (Sweden)

    Wilma Regina Barrionuevo

    2001-04-01

    Full Text Available The pyrethroids bifenthrin, permethrin, cypermethrin and deltamethrin were extracted by solid phase extraction (SPE and solid phase microextraction (SPME. The analysis were performed on a gas chromatograph with electron capture detection (GC-ECD. Octadecil Silano-C18, Florisil and Silica stationary phases were studied for SPE. Better results were obtained for Florisil which gave recoveries from 80% to 108%. Pyrethroids extraction by SPME showed a linear response and a detection limit of 10 pg ml-1. Although the data showed that the two extraction methods were able to isolate the pesticide residues from water samples, the best results were obtained by using SPME which is more sensitive, faster, cheeper, being a more useful technique for the analysis of pyrethroids in drinking water.

  9. Olive Oil Headspace Characterization by a Gas Sensor Array

    International Nuclear Information System (INIS)

    Santonico, Marco; Capuano, Rosamaria; Catini, Alexandro; Dini, Francesca; Martinelli, Eugenio; Gianni, Giacomo; Migliorini, Marzia; Paolesse, Roberto; D'Amico, Arnaldo; Di Natale, Corrado

    2011-01-01

    Olive oil quality is strictly correlated to the volatile compounds profile. Both quality and defects can be connected to the presence of specific volatile compounds in the oil headspace. In this paper, olive oil samples have been artificially modified by adding a number of compounds known to be typical of the more frequent defects: fusty, musty, muddy and rancid. Results demonstrate the sensitivity of the electronic nose to the compounds characterizing the defects and then the capability of the instrument to identify the defects in real samples.

  10. Direct determination of anabolic steroids in pig urine by a new SPME-GC-MS method.

    Science.gov (United States)

    Zhang, Zhuomin; Duan, Hongbin; Zhang, Lan; Chen, Xi; Liu, Wei; Chen, Guonan

    2009-05-15

    A new solid phase microextraction (SPME) method coupled with gas chromatography-mass spectrometry (GC-MS) was developed for rapid determination of four anabolic steroids such as 3alpha-hydroxy-5alpha-androstane-17-one (HA), dihydrotestosterone (DHT), androstenedione (AD) and methyltestosterone (MT) in pig urine. SPME was used to extract the four anabolic compounds directly without derivatization. The optimum SPME sampling conditions were based on the home-made carbowax-divinylbenzene (CW-DVB) fiber coating during extraction at 40 degrees C for 50 min with 0.18 g/mL NaCl solution and 750 rpm stirring speed. The linear ranges of the proposed method were in the range of 8-640 pg/mL for HA and DHT and 16-510 pg/mL for AD and MT, respectively. The detection limits (S/N=3) were from 2 to 8 pg/mL for the four anabolic steroids. This SPME method provided very high enrichment factors for the four anabolic steroids, which were 1063-fold and 965-fold for HA and DHT at the concentration of 8 pg/mL and 207-fold and 451-fold for AD and MT at the concentration of 16 pg/mL, respectively. The recoveries ranged from 71.3 to 121%, and the RSDs were lower than 12.9%. The method was sensitive and reliable for determination of trace anabolic steroids in biological samples.

  11. Using SPME fibers and Tenax to predict the bioavailability of pyrethroids and chlorpyrifos in field sediments

    International Nuclear Information System (INIS)

    Harwood, Amanda D.; Landrum, Peter F.; Weston, Donald P.; Lydy, Michael J.

    2013-01-01

    The presence of pyrethroids in both urban and agricultural sediments at levels lethal to invertebrates has been well documented. However, variations in bioavailability among sediments make accurate predictions of toxicity based on whole sediment concentrations difficult. A proposed solution to this problem is the use of bioavailability-based estimates, such as solid phase microextraction (SPME) fibers and Tenax beads. This study compared three methods to assess the bioavailability and ultimately toxicity of pyrethroid pesticides including field-deployed SPME fibers, laboratory-exposed SPME fibers, and a 24-h Tenax extraction. The objective of the current study was to compare the ability of these methods to quantify the bioavailable fraction of pyrethroids in contaminated field sediments that were toxic to benthic invertebrates. In general, Tenax proved a more sensitive method than SPME fibers and a correlation between Tenax extractable concentrations and mortality was observed. - Highlights: ► Can use bioavailability-based methods for pyrethroids in sediments. ► Tenax was a more sensitive technique. ► Tenax extractable concentrations relate to invertebrate mortality. - This research provides an important first step in using bioavailability-based techniques for estimating the bioavailability and toxicity of hydrophobic pesticides in field sediments.

  12. SPME as a tool in WEA - CONCAWE Contribution to OSPAR Demonstration Project 2005 - 2006

    NARCIS (Netherlands)

    Leslie, H.A.

    2006-01-01

    This document represents a compilation of various data and deliverables from the study programme. An executive summary is followed by the presentation of data generated in an interlaboratory study of effluents assessed using both EGOM-LLE and biomimetic SPME methods.

  13. Development of a GC-MS-SPME Method for the Determination of Amines in Meteorites

    Science.gov (United States)

    Hilts, R. W.; Skelhorne, A. W.; Simkus, D.; Herd, C. D. K.

    2016-08-01

    A GC-MS-SPME analytical method for the direct determination of amines in aqueous solution has been developed. The key step in the procedure is the conversion of the amines into their non-volatile ammonium salts by protonation with HCl.

  14. Comparison of two methods for extraction of volatiles from marine PL emulsions

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Jacobsen, Charlotte

    2013-01-01

    The dynamic headspace (DHS) thermal desorption principle using Tenax GR tube, as well as the solid phase micro‐extraction (SPME) tool with carboxen/polydimethylsiloxane 50/30 µm CAR/PDMS SPME fiber, both coupled to GC/MS were implemented for the isolation and identification of both lipid...... and Strecker derived volatiles in marine phospholipids (PL) emulsions. Comparison of volatile extraction efficiency was made between the methods. For marine PL emulsions with a highly complex composition of volatiles headspace, a fiber saturation problem was encountered when using CAR/PDMS‐SPME for volatiles...... analysis. However, the CAR/PDMS‐SPME technique was efficient for lipid oxidation analysis in emulsions of less complex headspace. The SPME method extracted volatiles of lower molecular weights more efficient than the DHS method. On the other hand, DHS Tenax GR appeared to be more efficient in extracting...

  15. Recognition of beer brand based on multivariate analysis of volatile fingerprint.

    Science.gov (United States)

    Cajka, Tomas; Riddellova, Katerina; Tomaniova, Monika; Hajslova, Jana

    2010-06-18

    Automated head-space solid-phase microextraction (HS-SPME)-based sampling procedure, coupled to gas chromatography-time-of-flight mass spectrometry (GC-TOFMS), was developed and employed for obtaining of fingerprints (GC profiles) of beer volatiles. In total, 265 speciality beer samples were collected over a 1-year period with the aim to distinguish, based on analytical (profiling) data, (i) the beers labelled as Rochefort 8; (ii) a group consisting of Rochefort 6, 8, 10 beers; and (iii) Trappist beers. For the chemometric evaluation of the data, partial least squares discriminant analysis (PLS-DA), linear discriminant analysis (LDA), and artificial neural networks with multilayer perceptrons (ANN-MLP) were tested. The best prediction ability was obtained for the model that distinguished a group of Rochefort 6, 8, 10 beers from the rest of beers. In this case, all chemometric tools employed provided 100% correct classification. Slightly worse prediction abilities were achieved for the models "Trappist vs. non-Trappist beers" with the values of 93.9% (PLS-DA), 91.9% (LDA) and 97.0% (ANN-MLP) and "Rochefort 8 vs. the rest" with the values of 87.9% (PLS-DA) and 84.8% (LDA) and 93.9% (ANN-MLP). In addition to chromatographic profiling, also the potential of direct coupling of SPME (extraction/pre-concentration device) with high-resolution TOFMS employing a direct analysis in real time (DART) ion source has been demonstrated as a challenging profiling approach. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  16. Effects of headspace fraction and aqueous alkalinity on subcritical hydrothermal gasification of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Ryan; Yin, Sudong; Tan, Zhongchao [Department of Mechanical and Manufacturing Engineering, Centre for Environmental Engineering Research and Education, Schulich School of Engineering, University of Calgary, 2500 University Dr. N.W. Calgary, AB (Canada)

    2010-07-15

    In order to better understand the pathways of hydrothermal gasification of cellulose, the effect of headspace fraction and alkalinity on the hydrothermal gasification of cellulose has been studied at 315 C in the presence of Pt/Al{sub 2}O{sub 3} as catalyst. It was found that regardless of alkalinity the headspace fraction had a large impact on gasification yield, with larger headspace fractions resulting in considerably more gas product. Without the addition of sodium carbonate, the effect of headspace fraction became more pronounced, with gas increasing by approximately a factor of forty from the lowest to highest headspace fraction. On the other hand, for the same residence time the addition of sodium carbonate co-catalyst dampened the magnitude of the effect, to a factor of 2.5 and 1.5, for 50 and 100 mM sodium carbonate solutions, respectively. These results indicated that the headspace fraction affected the phase behaviour, and that this altered the pathway of the cellulose decomposition. While furfural alcohol was the major product obtained with a 49% headspace fraction, it was effectively suppressed by using 78% or greater headspace fractions. Based on the effects of phase behaviour and previous literature, the reduced effect occurring upon the addition of sodium carbonate may relate to catalysis of the Lobry de-bruyn Van Eckenstein transform to produce lactic acid rather than intermediates proceeding through glycolaldehyde. (author)

  17. Bepaling van tetrachloor- en trichloorethyleen in olijfolie met behulp van headspace - gaschromatografie

    NARCIS (Netherlands)

    Roos, A.H.; Mazijk, van R.J.; Tuinstra, L.G.M.Th.

    1990-01-01

    De resultaten van de EEG headspace methode wijzen uit dat de herhaalbaarheid en nauwkeurigheid voldoende zijn om tetrachloor- en trichloorethyleen in olijfolie te bepalen tot een niveau van 0,01 mg/kg op produkt. De headspace techniek is door de eenvoudige procedure zeer geschikt voor routine

  18. Simplex Optimization of Headspace-Enrichment Conditions of Residual Petroleum Distillates Used by Arsonists

    Science.gov (United States)

    Warnke, Molly M.; Erickson, Angela E.; Smith, Eugene T.

    2005-01-01

    A forensic project is described that is suitable for an undergraduate instrumental methods lab. Accelerants commonly used by arsonists are analyzed by static headspace enrichment followed by gas chromatography. The conditions used for headspace enrichment (e.g., time and temperature) are known to influence the distribution of hydrocarbons…

  19. Análise de fármacos em material biológico: acoplamento microextração em fase sólida "no tubo" e cromatografia líquida de alta eficiência Analysis of drugs in biological samples: automated "in-tube" solid-phase microextraction and high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Maria Eugênia C. Queiroz

    2005-10-01

    Full Text Available A new solid phase microextraction (SPME system, known as in-tube SPME, was recently developed using an open tubular fused-silica capilary column, instead of an SPME fiber, as the SPME device. On-line in-tube SPME is usually used in combination with high performance liquid chromatography. Drugs in biological samples are directly extracted and concentrated in the stationary phase of capillary columns by repeated draw/eject cycles of sample solution, and then directly transferred to the liquid chromatographic column. In-tube SPME is suitable for automation. Automated sample handling procedures not only shorten the total analysis time, but also usually provide better accuracy and precision relative to manual techniques. In-tube SPME has been demonstrated to be a very effective and highly sensitive technique to determine drugs in biological samples for various purposes such as therapeutic drug monitoring, clinical toxicology, bioavailability and pharmacokinetics.

  20. Optimization of total vaporization solid-phase microextraction (TV-SPME) for the determination of lipid profiles of Phormia regina, a forensically important blow fly species.

    Science.gov (United States)

    Kranz, William; Carroll, Clinton; Dixon, Darren; Picard, Christine; Goodpaster, John

    2017-11-01

    A new method has been developed for the determination of fatty acids, sterols, and other lipids which naturally occur within pupae of the blow fly Phormia regina. The method relies upon liquid extraction in non-polar solvent, followed by derivatization using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) w/ 1% trimethylchlorsilane (TMCS) carried out inside the sample vial. The analysis is facilitated by total vaporization solid-phase microextraction (TV-SPME), with gas chromatography-mass spectrometry (GC-MS) serving as the instrumentation for analysis. The TV-SPME delivery technique is approximately a factor of five more sensitive than traditional liquid injection, which may alleviate the need for rotary evaporation, reconstitution, collection of high performance liquid chromatography fractions, and many of the other pre-concentration steps that are commonplace in the current literature. Furthermore, the ability to derivatize the liquid extract in a single easy step while increasing sensitivity represents an improvement over current derivatization methods. The most common lipids identified in fly pupae were various saturated and unsaturated fatty acids ranging from lauric acid (12:0) to arachinoic acid (20:4), as well as cholesterol. The concentrations of myristic acid (14:0), palmitelaidic acid (16:2), and palmitoleic acid (16:1) were the most reliable indicators of the age of the pupae. Graphical abstract Blow fly pupae were extracted prior to emerging as adults. The extracts were analyzed via total vaporization solid-phase microextraction (TV-SPME), revealing a complex mixture of lipids that could be associated with the age of the insect. This information may assist in determining a post-mortum interval (PMI) in a death investigation.

  1. A simple headspace equilibration method for measuring dissolved methane

    Science.gov (United States)

    Magen, C; Lapham, L.L.; Pohlman, John W.; Marshall, Kristin N.; Bosman, S.; Casso, Michael; Chanton, J.P.

    2014-01-01

    Dissolved methane concentrations in the ocean are close to equilibrium with the atmosphere. Because methane is only sparingly soluble in seawater, measuring it without contamination is challenging for samples collected and processed in the presence of air. Several methods for analyzing dissolved methane are described in the literature, yet none has conducted a thorough assessment of the method yield, contamination issues during collection, transport and storage, and the effect of temperature changes and preservative. Previous extraction methods transfer methane from water to gas by either a "sparge and trap" or a "headspace equilibration" technique. The gas is then analyzed for methane by gas chromatography. Here, we revisit the headspace equilibration technique and describe a simple, inexpensive, and reliable method to measure methane in fresh and seawater, regardless of concentration. Within the range of concentrations typically found in surface seawaters (2-1000 nmol L-1), the yield of the method nears 100% of what is expected from solubility calculation following the addition of known amount of methane. In addition to being sensitive (detection limit of 0.1 ppmv, or 0.74 nmol L-1), this method requires less than 10 min per sample, and does not use highly toxic chemicals. It can be conducted with minimum materials and does not require the use of a gas chromatograph at the collection site. It can therefore be used in various remote working environments and conditions.

  2. Cannabinoids determination in oral fluid by SPME-GC/MS and UHPLC-MS/MS and its application on suspected drivers.

    Science.gov (United States)

    Anzillotti, Luca; Castrignanò, Erika; Strano Rossi, Sabina; Chiarotti, Marcello

    2014-12-01

    The confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid (OF) is an important issue for assessing Driving Under the Influence of Drugs (DUID). The aim of this research was to develop a highly sensitive method with minimal sample pre-treatment suitable for the analysis of small OF volumes (100 μL) for the confirmation of cannabinoids in DUID cases. Two methods were compared for the confirmation of THC in residual OF samples, obtained from a preliminary on-site screening with commercial devices. An ultra high performance LC-MS (UHPLC-MS/MS) method and an SPME-GC/MS method were hence developed. 100 μL of the residual mixture OF/preservative buffer or neat OF was simply added to 10 μL of THC-D3 (1 μg/mL) and submitted to the two different analyses: A - direct injection of 10 μL in UHPLC-MS/MS in positive electrospray ionisation (ESI) mode and B - sampling for 30 min with SPME (100 μm polydimethylsiloxane or PDMS fibre) and direct injection by desorption of the fibre in the GC injection port. The lowest limit of detection (LLOD) of THC was 2 ng/mL in UHPLC-MS/MS and 0.5 ng/mL in SPME-GC/MS. In addition, cannabidiol (CBD) and cannabinol (CBN) could be detected in GC/MS equipment at 2 ng/mL, whilst in UHPLC-MS/MS the LLOD was 20 ng/mL. Both methods were applied to 70 samples coming from roadside tests. By SPME-GC/MS analysis, THC was confirmed in 42 samples, whilst CBD was detected in 21 of them, along with CBN in 14 samples. THC concentrations ranged from traces below the lowest limit of quantification or LLOQ (2 ng/mL) up to 690 ng/mL. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  3. Determination of microstickies in recycled whitewater by headspace gas chromatography.

    Science.gov (United States)

    Chai, X-S; Samp, J C; Yang, Q F; Song, H N; Zhang, D C; Zhu, J Y

    2006-03-03

    This study proposed a novel headspace gas chromatographic (HS-GC) method for determination of adhesive contaminants (microstickies) in recycled whitewater, a fiber containing process stream, in the paper mill. It is based on the adsorption behavior of toluene (as a tracer) on the hydrophobic surface of microstickies, which affects the apparent vapor-liquid equilibration partitioning of toluene. It was found that the equilibrium concentration of toluene in the vapor phase is inversely proportional to the apparent effective surface area of microstickies that remain in the corresponding solution. Thus, the amount of microsticky materials in the recycled whitewater can be quantified by HS-GC via indirect measurement of the toluene content in the vapor phase of the sample without any pretreatment. The presented method is simple, rapid and automated.

  4. Comprehensive quality evaluation of medical Cannabis sativa L. inflorescence and macerated oils based on HS-SPME coupled to GC-MS and LC-HRMS (q-exactive orbitrap®) approach.

    Science.gov (United States)

    Calvi, Lorenzo; Pentimalli, Daniela; Panseri, Sara; Giupponi, Luca; Gelmini, Fabrizio; Beretta, Giangiacomo; Vitali, Davide; Bruno, Massimo; Zilio, Emanuela; Pavlovic, Radmila; Giorgi, Annamaria

    2018-02-20

    There are at least 554 identified compounds in C. sativa L., among them 113 phytocannabinoids and 120 terpenes. Phytocomplex composition differences between the pharmaceutical properties of different medical cannabis chemotype have been attributed to strict interactions, defined as 'entourage effect', between cannabinoids and terpenes as a result of synergic action. The chemical complexity of its bioactive constituents highlight the need for standardised and well-defined analytical approaches able to characterise the plant chemotype, the herbal drug quality as well as to monitor the quality of pharmaceutical cannabis extracts and preparations. Hence, in the first part of this study an analytical procedures involving the combination of headspace-solid-phase microextraction (HS-SPME) coupled to GC-MS and High Resolution Mass-Spectrometry LC-HRMS (Orbitrap ® ) were set up, validated and applied for the in-depth profiling and fingerprinting of cannabinoids and terpenes in two authorised medical grade varieties of Cannabis sativa L. inflorescences (Bedrocan ® and Bediol ® ) and in obtained macerated oils. To better understand the trend of all volatile compounds and cannabinoids during oil storage a new procedure for cannabis macerated oil preparation without any thermal step was tested and compared with the existing conventional methods to assess the potentially detrimental effect of heating on overall product quality. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Influence of different salting processes on the evolution of the volatile metabolites of vacuum-packed fillets of farmed and wild sea bass (Dicentrarchus labrax) stored under refrigeration conditions: a study by SPME-GC/MS.

    Science.gov (United States)

    Vidal, Natalia P; Manzanos, María J; Goicoechea, Encarnación; Guillén, María D

    2017-02-01

    Fish shelf-life extension is a topic of great interest. In this study the behaviour of salted and unsalted farmed and wild European sea bass (Dicentrarchus labrax) fillets during storage was analysed through the evolution of their volatile metabolites. Farmed and wild sea bass fillets were brine-salted for 15 or 75 min, or dry-salted, vacuum-packed and stored at 4 °C for up to 1 month, and their headspaces were studied by Solid Phase Micro extraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS). At the same storage time, unsalted wild fillets contained, in general, a higher number and abundance of volatile compounds coming from microbiological or endogenous enzymatic activity than unsalted farmed ones. The more intense the salting, the lower the number and abundance of microbiological spoilage metabolites, especially in wild samples. The appearance of oxidation metabolites only in dry-salted wild samples evidences that this kind of salting provokes a certain oxidation in these samples. The better performance of farmed than wild fillets suggests that salted farmed fillets, vacuum-packed and stored under refrigeration conditions, could be a successful alternative to diversify the presence of sea bass in the market. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Optimization of the Extraction of the Volatile Fraction from Honey Samples by SPME-GC-MS, Experimental Design, and Multivariate Target Functions

    Directory of Open Access Journals (Sweden)

    Elisa Robotti

    2017-01-01

    Full Text Available Head space (HS solid phase microextraction (SPME followed by gas chromatography with mass spectrometry detection (GC-MS is the most widespread technique to study the volatile profile of honey samples. In this paper, the experimental SPME conditions were optimized by a multivariate strategy. Both sensitivity and repeatability were optimized by experimental design techniques considering three factors: extraction temperature (from 50°C to 70°C, time of exposition of the fiber (from 20 min to 60 min, and amount of salt added (from 0 to 27.50%. Each experiment was evaluated by Principal Component Analysis (PCA that allows to take into consideration all the analytes at the same time, preserving the information about their different characteristics. Optimal extraction conditions were identified independently for signal intensity (extraction temperature: 70°C; extraction time: 60 min; salt percentage: 27.50% w/w and repeatability (extraction temperature: 50°C; extraction time: 60 min; salt percentage: 27.50% w/w and a final global compromise (extraction temperature: 70°C; extraction time: 60 min; salt percentage: 27.50% w/w was also reached. Considerations about the choice of the best internal standards were also drawn. The whole optimized procedure was than applied to the analysis of a multiflower honey sample and more than 100 compounds were identified.

  7. Development of an SPME-GC-MS method for the specific quantification of dimethylamine and trimethylamine: use of a new ratio for the freshness monitoring of cod fillets.

    Science.gov (United States)

    Dehaut, Alexandre; Duthen, Simon; Grard, Thierry; Krzewinski, Frédéric; N'Guessan, Assi; Brisabois, Anne; Duflos, Guillaume

    2016-08-01

    Fish is a highly perishable food, so it is important to be able to estimate its freshness to ensure optimum quality for consumers. The present study describes the development of an SPME-GC-MS technique capable of quantifying both trimethylamine (TMA) and dimethylamine (DMA), components of what has been defined as partial volatile basic nitrogen (PVB-N). This method was used, together with other reference methods, to monitor the storage of cod fillets (Gadus morhua) conserved under melting ice. Careful optimisation enabled definition of the best parameters for extracting and separating targeted amines and an internal standard. The study of cod spoilage by sensory analysis and TVB-N assay led to the conclusion that the shelf-life of cod fillet was between 6 and 7 days. Throughout the study, TMA and DMA were specifically quantified by SPME-GC-MS; the first was found to be highly correlated with the values returned by steam distillation assays. Neither TMA-N nor DMA-N were able to successfully characterise the decrease in early freshness, unlike dimethylamine/trimethylamine ratio (DTR), whose evolution is closely related to the results of sensory analysis until the stage where fillets need to be rejected. DTR was proposed as a reliable indicator for the early decrease of freshness until fish rejection. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  8. Evaluation of the volatile profile of Tuber liyuanum by HS-SPME with GC-MS.

    Science.gov (United States)

    Liu, Changjiao; Li, Yu

    2017-04-01

    The volatile components of Tuber liyuanum were determined by HS-SPME with GC-MS for the first time. The effects of different fibre coating, extraction time, extraction temperature and sample amount were studied to get optimal extraction conditions. The optimal conditions were SPME fibre of Carboxen/PDMS, extraction time of 40 min, extraction temperature of 80 °C, sample amount of 2 g. Under these conditions 57 compounds in volatile of T. liyuanum were detected with a resemblance percentage above 80%. Aldehydes and aromatics were the main chemical families identified. The contribution of 3-Octanone(11.67%), phenylethyl alcohol (10.60%), isopentana (9.29%) and methylbutana (8.06%) for the total volatile profile were more significant in T. liyuanum than other compounds.

  9. Solid-phase microextraction for the analysis of biological samples

    NARCIS (Netherlands)

    Theodoridis, G; Koster, EHM; de Jong, GJ

    2000-01-01

    Solid-phase microextraction (SPME) has been introduced for the extraction of organic compounds from environmental samples. This relatively new extraction technique has now also gained a lot of interest in a broad field of analysis including food, biological and pharmaceutical samples. SPME has a

  10. Polycyclic aromatic hydrocarbons bioavailability in industrial and agricultural soils: Linking SPME and Tenax extraction with bioassays.

    Science.gov (United States)

    Guo, Meixia; Gong, Zongqiang; Li, Xiaojun; Allinson, Graeme; Rookes, James; Cahill, David

    2017-06-01

    The aims of this study were to evaluate the bioavailability of polycyclic aromatic hydrocarbons (PAHs) in industrial and agricultural soils using chemical methods and a bioassay, and to study the relationships between the methods. This was conducted by comparing the quantities of PAHs extracted from two manufactured gas plant (MGP) soils and an agricultural soil with low level contamination by solid-phase micro-extraction (SPME) and Tenax-TA extraction with the quantities taken up by the earthworm (Eisenia fetida). In addition, a biodegradation experiment was conducted on one MGP soil (MGP-A) to clarify the relationship between PAH removal by biodegradation and the variation in PAH concentrations in soil pore water. Results demonstrated that the earthworm bioassay could not be used to examine PAH bioavailability in the tested MGP soils; which was the case even in the diluted MGP-A soils after biodegradation. However, the bioassay was successfully applied to the agricultural soil. These results suggest that earthworms can only be used for bioassays in soils with low toxicity. In general, rapidly desorbing concentrations extracted by Tenax-TA could predict PAH concentrations accumulated in earthworms (R 2 =0.66), while SPME underestimated earthworm concentrations by a factor of 2.5. Both SPME and Tenax extraction can provide a useful tool to predict PAH bioavailability for earthworms, but Tenax-TA extraction was proven to be a more sensitive and precise method than SPME for the prediction of earthworm exposure in the agricultural soil. Copyright © 2017. Published by Elsevier Inc.

  11. Volatiles in Breath and Headspace Analysis - Diagnostic Markers

    Science.gov (United States)

    2017-07-24

    Tuberculosis; Gastric Cancer; Peptic Ulcer; Atrophic Gastritis; Intestinal Metaplasia; Gastric Dysplasia; Colorectal Cancer; Colorectal Polyp; Colorectal Adenoma; Pancreatic Cancer; Pancreatitis, Chronic; Liver Cancer; Liver Cirrhosis; Flu, Human; Other Infectious Diseases; Inflammatory Bowel Diseases

  12. EVALUACIÓN DE PLAGUICIDAS 0RGAN0CL0RAD0S POR HS-SPME - GC/ECD EN LECHE PASTEURIZADA COMERCIALIZADA EN LA CIUDAD DE CARTAGENA (COLOMBIA A AVALIAQÁO DOS PESTICIDAS ORGANOCLORADOS POR HS-SPME - GC/ECD EM LEITE PASTEURIZADO COMERCIALIZADAS NA CIDADE CARTAGENA (COLOMBIA EVALUATION OF PESTICIDES BY HS-SPME ORGANOCHLORINE - GC / ECD IN PASTEURIZED MILK MARKETED IN THE CITY CARTAGENA (COLOMBIA

    Directory of Open Access Journals (Sweden)

    DENILES DEL CARMEN DE ARCO R

    2011-12-01

    Full Text Available Los plaguicidas han sido utilizados en todo el mundo desde mediados del siglo XX, en campañas de Salud Pública y en prácticas agrícolas. Los Plaguicidas Organoclorados (POCs presentan mayor impacto sobre el ambiente porque no son biodegradables, son lipofílicos, tienen gran movilidad por todo el planeta y gran tendencia a la bioacumulación, através de la cadena trófica. Con el objetivo de identificar y cuantificar plaguicidas organoclorados en leche entera pasteurizada de dos marcas (A y B, que se comercializan en la ciudad de Cartagena de Indias, se realizó la presente investigación, utilizando Microextracción en Fase Sólida en Espacio de Cabeza y Cromatografía de Gases con Detector de Captura de Electrones (HS-SPME-GC/ECD. Fueron analizadas 36 muestras (n=36, 18 de cada marca. El 100% de las muestras (n=36 resultaron positivas para el plaguicida lindano (γ-HCH, superando el Límite Máximo Residual (LMR de 0,01 mg/kg, establecido por la Food and Agriculture Organization y la Organización Mundial de la Salud (FAO/OMS. Las concentraciones promedio de lindano obtenidas para la marca A fueron de 0,042 mg/kg ± 0,003 y 0,062 ± 0,0016 mg/kg (base grasa para la marca B, no superando la Ingesta Diaria Admisible (IDA de 0,001 mg/kg de peso corporal.Os pesticidas têm sido usados em todo o mundo desde meados do século XX, as campanhas de saúde pública e práticas agrícolas. Os inseticidas organoclorados (AP têm maior impacto sobre o meio ambiente porque não são biodegradáveis, são lipofílicas, têm grande mobilidade ao redor do mundo e maior tendencia para a bioacumulação através da cadeia alimentar. A fim de identificar e quantificar pesticidas organoclorados em leite integral, duas marcas (A e B, comercializada na cidade de Cartagena das Índias, a presente investigação foi realizada por cromatografia em Fase Sólida, Microextração Headspace Gás com Detector de Captura de Elétrons(HS-SPME-GC/ECD. 36 amostras foram

  13. Characterization of wood plastic composites made from landfill-derived plastic and sawdust: Volatile compounds and olfactometric analysis

    International Nuclear Information System (INIS)

    Félix, Juliana S.; Domeño, Celia; Nerín, Cristina

    2013-01-01

    Graphical abstract: This work details the characterization of VOCs of WPC, produced from residual materials which would have landfills as current destination, and evaluates their odor profile. Highlights: ► More than 140 volatile compounds were identified in raw materials and WPC products. ► Markers were related to the thermal degradation, sawdust or coupling agents. ► WPC prototype showed a characteristic odor profile of burnt, sweet and wax-like. ► Aldehydes, carboxylic acids, ketones and phenols were odor descriptors of WPC. - Abstract: Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by their composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC

  14. Characterization of wood plastic composites made from landfill-derived plastic and sawdust: Volatile compounds and olfactometric analysis

    Energy Technology Data Exchange (ETDEWEB)

    Félix, Juliana S., E-mail: jfelix@unizar.es [Department of Analytical Chemistry, I3A, EINA, University of Zaragoza (UNIZAR), Zaragoza 50018 (Spain); Domeño, Celia, E-mail: cdomeno@unizar.es [Department of Analytical Chemistry, I3A, EINA, University of Zaragoza (UNIZAR), Zaragoza 50018 (Spain); Nerín, Cristina, E-mail: cnerin@unizar.es [Department of Analytical Chemistry, I3A, EINA, University of Zaragoza (UNIZAR), Zaragoza 50018 (Spain)

    2013-03-15

    Graphical abstract: This work details the characterization of VOCs of WPC, produced from residual materials which would have landfills as current destination, and evaluates their odor profile. Highlights: ► More than 140 volatile compounds were identified in raw materials and WPC products. ► Markers were related to the thermal degradation, sawdust or coupling agents. ► WPC prototype showed a characteristic odor profile of burnt, sweet and wax-like. ► Aldehydes, carboxylic acids, ketones and phenols were odor descriptors of WPC. - Abstract: Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by their composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC.

  15. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Waste Tank U-203, Results from samples collected on August 8, 1995

    International Nuclear Information System (INIS)

    Pool, K.H.; Clauss, T.W.; Evans, J.C.; McVeety, B.D.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S.; Ligotke, M.W.

    1995-11-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-U-203 (Tank U-203) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank-farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest Laboratory (PNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the results is listed. Detailed descriptions of the analytical results appear in the text

  16. Tank Vapor Characterization Project. Headspace vapor characterization of Hanford Waste Tank AX-102: Results from samples collected on June 27, 1995

    International Nuclear Information System (INIS)

    Clauss, T.W.; Pool, K.H.; Evans, J.C.; McVeety, B.D.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S.; Ligotke, M.W.

    1995-11-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-AX-102 (Tank AX-102) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank-farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest Laboratory (PNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. Detailed descriptions of the analytical results appear in the text

  17. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Tank 241-S-107: Results from samples collected on 06/18/96

    International Nuclear Information System (INIS)

    Pool, K.H.; Evans, J.C.; Thomas, B.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-S-107 (Tank S-107) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National. Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, on sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices

  18. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Waste Tank U-204, Results from samples collected on August 8, 1995

    International Nuclear Information System (INIS)

    Clauss, T.W.; Evans, J.C.; McVeety, B.D.; Pool, K.H.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S.; Ligotke, M.W.

    1995-11-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-U-204 (Tank U-204) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank-farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the results is listed. Detailed descriptions of the analytical results appear in the text

  19. Polyaniline-nylon-6 electrospun nanofibers for headspace adsorptive microextraction

    International Nuclear Information System (INIS)

    Bagheri, Habib; Aghakhani, Ali

    2012-01-01

    Highlights: ► Polyaniline–polyamide nanofiber mat was fabricated by electrospinning technology. ► Electrospun nanofiber was used for extraction of chlorobenzenes from aquatic media. ► A method based on headspace adsorptive microextraction and GC–MS was developed. - Abstract: A headspace adsorptive microextraction technique was developed using a novel polyaniline-nylon-6 (PANI-N6) nanofiber sheet, fabricated by electrospinning. The homogeneity and the porosity of the prepared PANI-N6 sheet were studied using the scanning electron microscopy (SEM) and nanofibers diameters were found to be around 200 nm. The novel nanofiber sheet was examined as an extracting medium to isolate some selected chlorobenzenes (CBs), as model compounds, from aquatic media. The extracted analytes were desorbed using μL-amounts of solvent and eventually an aliquot of extractant was injected into gas chromatography–mass spectrometry (GC–MS). Various parameters affecting the extraction and desorption processes were optimized. The developed method proved to be convenient and offers sufficient sensitivity and a good reproducibility. Limits of detection achieved for CBs with the developed analytical procedure ranged from 19 to 33 ng L −1 , while limits of quantification were from 50 to 60 ng L −1 . The relative standard deviations (RSD) at a concentration level of 0.1 ng mL −1 and 1 ng mL −1 were in the range of 8–14% and 5–11% (n = 3), respectively. The calibration curves of analytes were investigated in the range of 50–1000 ng L −1 and R 2 between 0.9739 and 0.9932 were obtained. The developed method was successfully applied to the extraction of selected CBs from tap and river water samples. The relative recovery (RR) percentage obtained for the spiked real water samples at 0.1 ng mL −1 and 1 ng mL −1 level were 93–103% and 95–104%, respectively. The whole procedure showed to be conveniently applicable and quite easy to handle.

  20. Polyaniline-nylon-6 electrospun nanofibers for headspace adsorptive microextraction

    Energy Technology Data Exchange (ETDEWEB)

    Bagheri, Habib, E-mail: bagheri@sharif.edu [Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of); Aghakhani, Ali [Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Polyaniline-polyamide nanofiber mat was fabricated by electrospinning technology. Black-Right-Pointing-Pointer Electrospun nanofiber was used for extraction of chlorobenzenes from aquatic media. Black-Right-Pointing-Pointer A method based on headspace adsorptive microextraction and GC-MS was developed. - Abstract: A headspace adsorptive microextraction technique was developed using a novel polyaniline-nylon-6 (PANI-N6) nanofiber sheet, fabricated by electrospinning. The homogeneity and the porosity of the prepared PANI-N6 sheet were studied using the scanning electron microscopy (SEM) and nanofibers diameters were found to be around 200 nm. The novel nanofiber sheet was examined as an extracting medium to isolate some selected chlorobenzenes (CBs), as model compounds, from aquatic media. The extracted analytes were desorbed using {mu}L-amounts of solvent and eventually an aliquot of extractant was injected into gas chromatography-mass spectrometry (GC-MS). Various parameters affecting the extraction and desorption processes were optimized. The developed method proved to be convenient and offers sufficient sensitivity and a good reproducibility. Limits of detection achieved for CBs with the developed analytical procedure ranged from 19 to 33 ng L{sup -1}, while limits of quantification were from 50 to 60 ng L{sup -1}. The relative standard deviations (RSD) at a concentration level of 0.1 ng mL{sup -1} and 1 ng mL{sup -1} were in the range of 8-14% and 5-11% (n = 3), respectively. The calibration curves of analytes were investigated in the range of 50-1000 ng L{sup -1} and R{sup 2} between 0.9739 and 0.9932 were obtained. The developed method was successfully applied to the extraction of selected CBs from tap and river water samples. The relative recovery (RR) percentage obtained for the spiked real water samples at 0.1 ng mL{sup -1} and 1 ng mL{sup -1} level were 93-103% and 95-104%, respectively. The whole procedure showed

  1. Determination of residual acetone and acetone related impurities in drug product intermediates prepared as Spray Dried Dispersions (SDD) using gas chromatography with headspace autosampling (GCHS).

    Science.gov (United States)

    Quirk, Emma; Doggett, Adrian; Bretnall, Alison

    2014-08-05

    Spray Dried Dispersions (SDD) are uniform mixtures of a specific ratio of amorphous active pharmaceutical ingredient (API) and polymer prepared via a spray drying process. Volatile solvents are employed during spray drying to facilitate the formation of the SDD material. Following manufacture, analytical methodology is required to determine residual levels of the spray drying solvent and its associated impurities. Due to the high level of polymer in the SDD samples, direct liquid injection with Gas Chromatography (GC) is not a viable option for analysis. This work describes the development and validation of an analytical approach to determine residual levels of acetone and acetone related impurities, mesityl oxide (MO) and diacetone alcohol (DAA), in drug product intermediates prepared as SDDs using GC with headspace (HS) autosampling. The method development for these analytes presented a number of analytical challenges which had to be overcome before the levels of the volatiles of interest could be accurately quantified. GCHS could be used after two critical factors were implemented; (1) calculation and application of conversion factors to 'correct' for the reactions occurring between acetone, MO and DAA during generation of the headspace volume for analysis, and the addition of an equivalent amount of polymer into all reference solutions used for quantitation to ensure comparability between the headspace volumes generated for both samples and external standards. This work describes the method development and optimisation of the standard preparation, the headspace autosampler operating parameters and the chromatographic conditions, together with a summary of the validation of the methodology. The approach has been demonstrated to be robust and suitable to accurately determine levels of acetone, MO and DAA in SDD materials over the linear concentration range 0.008-0.4μL/mL, with minimum quantitation limits of 20ppm for acetone and MO, and 80ppm for DAA. Copyright

  2. Characterization and Assessment of Flavor Compounds and Some Allergens in Three Iranian Rice Cultivars during Gelatinization Process by HS-SPME/GC-MS

    Directory of Open Access Journals (Sweden)

    M. H. Givianrad

    2012-01-01

    Full Text Available A combined gas chromatography mass spectrometry with headspace solid-phase microextraction method has been utilized for the analysis of the flavor volatiles of three different rice cultivars including two modified Iranian rice cultivars and Hashemi rice cultivar during gelatinization. As a result, while gelatinization would progress, the amount of the volatile compounds would be also increased. Altogether, 74, 55 and 66 components were identified for Hashemi, HD5 and HD6 rice samples, respectively, which 56 unique compounds were not identified, previously. Subsequently, seven fragrance chemicals have been detected, which were most frequently reported as contact allergens in the European Union.

  3. Multiple responses optimization in the development of a headspace gas chromatography method for the determination of residual solvents in pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Carla M. Teglia

    2015-10-01

    Full Text Available An efficient generic static headspace gas chromatography (HSGC method was developed, optimized and validated for the routine determination of several residual solvents (RS in drug substance, using a strategy with two sets of calibration. Dimethylsulfoxide (DMSO was selected as the sample diluent and internal standards were used to minimize signal variations due to the preparative step. A gas chromatograph from Agilent Model 6890 equipped with flame ionization detector (FID and a DB-624 (30 m×0.53 mm i.d., 3.00 µm film thickness column was used. The inlet split ratio was 5:1. The influencing factors in the chromatographic separation of the analytes were determined through a fractional factorial experimental design. Significant variables: the initial temperature (IT, the final temperature (FT of the oven and the carrier gas flow rate (F were optimized using a central composite design. Response transformation and desirability function were applied to find out the optimal combination of the chromatographic variables to achieve an adequate resolution of the analytes and short analysis time. These conditions were 30 °C for IT, 158 °C for FT and 1.90 mL/min for F. The method was proven to be accurate, linear in a wide range and very sensitive for the analyzed solvents through a comprehensive validation according to the ICH guidelines. Keywords: Headspace gas chromatography, Residual solvents, Pharmaceuticals, Surface response methodology, Desirability function

  4. Headspace vapor characterization of Hanford waste tank 241-U-109: Results from samples collected on 8/10/95

    International Nuclear Information System (INIS)

    Evans, J.C.; Thomas, B.L.; Pool, K.H.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1996-05-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-U-109 (Tank U-109) At the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. This tank is on the Hydrogen Waste List. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases and total non-methane hydrocarbons is listed in a table. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples is also listed in the table. Detailed descriptions of the analytical results appear in the text

  5. Headspace vapor characterization of Hanford waste Tank 241-BX-110: Results from samples collected on 04/30/96

    International Nuclear Information System (INIS)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-BX-110 (Tank BX-110) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in a table. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in the table. Detailed descriptions of the analytical results appear in the appendices

  6. Determination of volatile organic compounds in eucalyptus fast pyrolysis bio-oil by full evaporation headspace gas chromatography.

    Science.gov (United States)

    Kosinski Lima, Nathalya; Romualdo Lopes, André; Gimenes Guerrero, Palimecio; Itsuo Yamamoto, Carlos; Augusto Hansel, Fabricio

    2018-01-01

    This paper reports a full evaporation (FE) headspace gas chromatographic (HS-GC) method for the determination of the volatile organic compounds (VOCs) in bio-oil (i.e. methanol, ethanol, acetone, acetic acid and furfural). The method uses a 4μL sample of bio-oil in a headspace vial (ca. 20mL). Complete evaporation of the compounds was achieved after seven minutes at 90°C. The method showed good precision and accuracy for methanol, ethanol, acetone and acetic acid. The recovery of furfural was low (74.3%). The results showed that the protocol can be applied for the determination of methanol, ethanol, acetone and acetic acid in bio-oil. Detection limits ranged from 0.13 to 0.16μg. Acetic acid was the dominant analyte in the heavy bio-oil and light bio-oil analysis (113. 3 and 85.1µgmg -1 , respectively), followed by methanol, ethanol, and acetone. The polymerisation of furfural was suspected as the cause of its poor quantification. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Metabolome based volatiles profiling in 13 date palm fruit varieties from Egypt via SPME GC-MS and chemometrics.

    Science.gov (United States)

    Khalil, Mohammed N A; Fekry, Mostafa I; Farag, Mohamed A

    2017-02-15

    Dates (Phoenix dactylifera L.) are distributed worldwide as major food complement providing a source of sugars and dietary fiber as well as macro- and micronutrients. Although phytochemical analyses of date fruit non-volatile metabolites have been reported, much less is known about the aroma given off by the fruit, which is critical for dissecting sensory properties and quality traits. Volatile constituents from 13 date varieties grown in Egypt were profiled using SPME-GCMS coupled to multivariate data analysis to explore date fruit aroma composition and investigate potential future uses by food industry. A total of 89 volatiles were identified where lipid-derived volatiles and phenylpropanoid derivatives were the major components of date fruit aroma. Multivariate data analyses revealed that 2,3-butanediol, hexanal, hexanol and cinnamaldehyde contributed the most to classification of different varieties. This study provides the most complete map of volatiles in Egyptian date fruit, with Siwi and Sheshi varieties exhibiting the most distinct aroma among studied date varieties. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Odor Profile of Different Varieties of Extra-Virgin Olive Oil During Deep Frying Using an Electronic Nose and SPME-GC-FID

    Science.gov (United States)

    Messina, Valeria; Biolatto, Andrea; Sancho, Ana; Descalzo, Adriana; Grigioni, Gabriela; de Reca, Noemí Walsöe

    2011-09-01

    The aim of the performed work was to evaluate with an electronic nose changes in odor profile of Arauco and Arbequina varieties of extra-virgin olive oil during deep-frying. Changes in odor were analyzed using an electronic nose composed of 16 sensors. Volatile compounds were analyzed by SPME-GC-FID. Principal Component Analysis was applied for electronic results. Arauco variety showed the highest response for sensors. Statistical analysis for volatile compounds indicated a significant (P<0.001) interaction between variety and time of frying processes. Arauco variety showed the highest production of volatile compounds at 60 min of deep frying. The two varieties presented distinct patterns of volatile products, being clearly identified with the electronic nose.

  9. VOLATILE COMPOUNDS OF LITHRAEA CAUSTICA (LITRE) DETERMINATED BY SOLID PHASE MICRO-EXTRACTION (SPME)

    OpenAIRE

    GARBARINO, JUAN A; SALVATORE, GIUSEPPE; PIVANOVO, MARISA; CHAMY, MARÍA CRISTINA; NICOLETTI, MARCELLO; DE IOANNES, ALFREDO

    2002-01-01

    The head space of the aerial parts of Lithraea caustica was analyzed by Solid Phase Micro-Extraction (SPME) technique, obtaining as main volatile compounds the monoterpenes, myrcene, a -pinene, , p-cymene and limonene, as well as the sesquiterpene caryophylene. De las partes áereas de Lithraea caustica y usando la técnica de Micro-Extracción en Fase Sólida (MEFS), fueron identificados y cuantificados los principales compuestos volátiles: los monoterpenos, mirceno, a -pineno, p-cimeno y lim...

  10. headspace - Australia's innovation in youth mental health: who are the clients and why are they presenting?

    Science.gov (United States)

    Rickwood, Debra J; Telford, Nic R; Parker, Alexandra G; Tanti, Chris J; McGorry, Patrick D

    2014-02-03

    To provide the first national profile of the characteristics of young people (aged 12-25 years) accessing headspace centre services - the Australian Government's innovation in youth mental health service delivery - and investigate whether headspace is providing early service access for adolescents and young adults with emerging mental health problems. Census of all young people accessing a headspace centre across the national network of 55 centres comprising a total of 21 274 headspace clients between 1 January and 30 June 2013. Reason for presentation, Kessler Psychological Distress Scale, stage of illness, diagnosis, functioning. Young people were most likely to present with mood and anxiety symptoms and disorders, self-reporting their reason for attendance as problems with how they felt. Client demographic characteristics tended to reflect population-level distributions, although clients from regional areas and of Aboriginal and Torres Strait Islander background were particularly well represented, whereas those who were born outside Australia were underrepresented. headspace centres are providing a point of service access for young Australians with high levels of psychological distress and need for care in the early stages of the development of mental disorder.

  11. The utilisation of two detectors for the determination of water in honey using headspace gas chromatography.

    Science.gov (United States)

    Frink, Lillian A; Armstrong, Daniel W

    2016-08-15

    A headspace gas chromatography (HSGC) method was developed for the determination of water content in honey. This method was shown to work with five different honey varieties which had a range of water from 14-16%. It also utilised two different detectors, the thermal conductivity detector (TCD) and the barrier discharge ionisation detector (BID). This method needs no heating pretreatment step as in the current leading method, (i.e. the measurement of refractive index). The solvent-free procedure negates the possibility of solvent-compound interactions as well as solubility limitations, as is common with Karl Fischer titrations. It was also apparent that the classic loss on drying method consistently and substantially produced results that were lower than the correct values. This approach is shown to be rapid, with an analysis time of 4 min when using the TCD detector and under 3 min when utilising the BID detector. HSGC is feasible for the determination of water due to the new PEG-linked geminal dicationic ionic-liquid-coated GC capillary column. In addition it provides accurate and precise determinations of the water content in honey. When using the sensitive BID detector, other trace volatile compounds are observed as well. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Headspace gas chromatographic method for the measurement of difluoroethane in blood.

    Science.gov (United States)

    Broussard, L A; Broussard, A; Pittman, T; Lafferty, D; Presley, L

    2001-01-01

    To develop a gas chromatographic assay for the analysis of difluoroethane, a volatile substance, in blood and to determine assay characteristics including linearity, limit of quantitation, precision, and specificity. Referral toxicology laboratory Difluoroethane, a colorless, odorless, highly flammable gas used as a refrigerant blend component and aerosol propellant, may be abused via inhalation. A headspace gas chromatographic procedure for the identification and quantitation of difluoroethane in blood is presented. A methanolic stock standard prepared from pure gaseous difluoroethane was used to prepare whole blood calibrators. Quantitation of difluoroethane was performed using a six-point calibration curve and an internal standard of 1-propanol. The assay is linear from 0 to 115 mg/L including a low calibrator at 4 mg/L, the limit of quantitation. Within-run coefficients of variation at mean concentrations of 13.8 mg/L and 38.5 mg/L were 5.8% and 6.8% respectively. Between-run coefficients of variation at mean concentrations of 15.9 mg/L and 45.7 mg/L were 13.4% and 9.8% respectively. Several volatile substances were tested as potential interfering compounds with propane having a retention time identical to that of difluoroethane. This method requires minimal sample preparation, is rapid and reproducible, can be modified for the quantitation of other volatiles, and could be automated using an automatic sampler/injector system.

  13. Optimization of Biochemical Screening Methods for Volatile and Unstable Sesquiterpenoids Using HS-SPME-GC-MS

    Directory of Open Access Journals (Sweden)

    Trine Bundgaard Andersen

    2015-06-01

    Full Text Available HS-SPME-GC-MS has been suggested as a fast and robust analytical platform for the product characterization of sesquiterpene synthases. The choice of fiber and injection temperature can have a significant effect on the observed product profile, due to the chemical rearrangements that can occur on the fiber material. Here we present a systematic study on the effects of fiber choice and injection port temperature on the observed sesquiterpenoid profile of four sesquiterpene synthases expressed in Nicotiana benthamiana. We found that the absorbent material PDMS was much less likely to support acid-induced rearrangement of sesquiterpenoids when compared to the adsorbent materials PDMS/DVB, PDMS/CAR, and PDMS/CAR/DVB. Furthermore, utilizing an injection port temperature at 160 °C almost eliminated the inherent thermal instability of germacrene sesquiterpenoids. Thus, for fast screening of sesquiterpene synthases, the results suggest that PDMS fibers and an injection temperature of 160 °C provide a fast and reproducible HS-SPME GC-MS method when using H2 as carrier gas.

  14. SPME-Based Ca-History Method for Measuring SVOC Diffusion Coefficients in Clothing Material.

    Science.gov (United States)

    Cao, Jianping; Liu, Ningrui; Zhang, Yinping

    2017-08-15

    Clothes play an important role in dermal exposure to indoor semivolatile organic compounds (SVOCs). The diffusion coefficient of SVOCs in clothing material (D m ) is essential for estimating SVOC sorption by clothing material and subsequent dermal exposure to SVOCs. However, few studies have reported the measured D m for clothing materials. In this paper, we present the solid-phase microextraction (SPME) based C a -history method. To the best of our knowledge, this is the first try to measure D m with known relative standard deviation (RSD). A thin sealed chamber is formed by a circular ring and two pieces of flat SVOC source materials that are tightly covered by the targeted clothing materials. D m is obtained by applying an SVOC mass transfer model in the chamber to the history of gas-phase SVOC concentrations (C a ) in the chamber measured by SPME. D m 's of three SVOCs, di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and tris(1-chloro-2-propyl) phosphate (TCPP), in a cotton T-shirt can be obtained within 16 days, with RSD less than 3%. This study should prove useful for measuring SVOC D m in various sink materials. Further studies are expected to facilitate application of this method and investigate the effects of temperature, relative humidity, and clothing material on D m .

  15. Comparative study of volatile components from male and female flower buds of Populus × tomentosa by HS-SPME-GC-MS.

    Science.gov (United States)

    Xu, Liang; Liu, Haiping; Ma, Yucui; Wu, Cui; Li, Ruiqi; Chao, Zhimao

    2018-06-13

    The differences of volatile components in male (MFB) and female flower buds (FFB) of Populus × tomentosa were analysed and compared by HS-SPME with GC-MS for the first time. A total of 34 compounds were identified. Two clusters were clearly divided into male and female by hierarchical clustering analysis. Both the male and female flower buds showed methyl salicylate (22.83 and 24.09%, respectively) and 2-hydroxy-benzaldehyde (10.05 and 12.41%, respectively) as the main volatile constituents. The content of 2-cyclohexen-1-one, benzyl benzoate, and methyl benzoate in FFB was remarkably higher than in MFB. In contrast, the content of ethyl benzoate in MFB was greater than that in FFB. The phenomena showed the characteristic differences between MFB and FFB of P. × tomentosa, which enriched the basic studies on dioecious plant.

  16. Greek Salvia sclarea L. Essential Oils: Effect of Hydrodistillation Time, Comparison of the Aroma Chemicals Using Hydrodistillation and HS-SPME Techniques

    Directory of Open Access Journals (Sweden)

    Aikaterini Koutsaviti

    2016-05-01

    Full Text Available Since the essential oil of Salvia sclarea is used as a flavouring agent, the effect of different extraction techniques (hydrodistillation & HS-SPME and duration of hydrodistillation (2, 3 and 4 h with respect to yield, composition and identification rate of extracted essential oils from Greek cultivated S. sclarea aerial blooming parts were investigated. Linalool and linalyl acetate levels seemed to decrease with increasing duration of hydrodistillation, while diterpenes increased dramatically, while the head space analysis showed significantly lower levels of linalool in comparison to its ester. Thus, linalool (5.1-35.8%, linalyl acetate (11.3-37.6% and sclareol (0.0-41.8%, concerning the oils obtained by hydrodistillation, were the most important metabolites. Solid-phase microextraction yielded mainly oxygenated monoterpenes, especially linalyl acetate (59.3%, followed by cis-linalool oxide (8.6% and linalool (7.8%.

  17. Assessing a traceability technique in fresh oranges (Citrus sinensis L. Osbeck) with an HS-SPME-GC-MS method. Towards a volatile characterisation of organic oranges.

    Science.gov (United States)

    Cuevas, Francisco Julián; Moreno-Rojas, José Manuel; Ruiz-Moreno, María José

    2017-04-15

    A targeted approach using HS-SPME-GC-MS was performed to compare flavour compounds of 'Navelina' and 'Salustiana' orange cultivars from organic and conventional management systems. Both varieties of conventional oranges showed higher content of ester compounds. On the other hand, higher content of some compounds related with the geranyl-diphosphate pathway (neryl and geranyl acetates) and some terpenoids were found in the organic samples. Furthermore, the partial least square discriminant analysis (PLS-DA) achieved an effective classification for oranges based on the farming system using their volatile profiles (90 and 100% correct classification). To our knowledge, it is the first time that a comparative study dealing with farming systems and orange aroma profile has been performed. These new insights, taking into account local databases, cultivars and advanced analytical tools, highlight the potential of volatile composition for organic orange discrimination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Headspace liquid-phase microextraction of methamphetamine and amphetamine in urine by an aqueous drop

    International Nuclear Information System (INIS)

    He Yi; Vargas, Angelica; Kang, Youn-Jung

    2007-01-01

    This study developed a headspace liquid-phase microextraction (LPME) method by using a single aqueous drop in combination with high performance liquid chromatography (HPLC)-UV detection for the determination of methamphetamine (MAP) and amphetamine (AP) in urine samples. The analytes, volatile and basic, were released from sample matrix into the headspace first, and then protonated and dissolved in an aqueous H 3 PO 4 drop hanging in the headspace by a HPLC syringe. After extraction, this drop was directly injected into HPLC. Parameters affecting extraction efficiency were investigated and optimized. This method showed good linearity in the investigated concentration range of 1.0-1500 μg L -1 , repeatability of the extraction (R.S.D. -1 for both analytes). Enrichment factors of about 400-fold and 220-fold were achieved for MAP and AP, respectively, at optimum conditions. The feasibility of the method was demonstrated by analyzing human urine samples

  19. Multiple internal standard normalization for improving HS-SPME-GC-MS quantitation in virgin olive oil volatile organic compounds (VOO-VOCs) profile.

    Science.gov (United States)

    Fortini, Martina; Migliorini, Marzia; Cherubini, Chiara; Cecchi, Lorenzo; Calamai, Luca

    2017-04-01

    The commercial value of virgin olive oils (VOOs) strongly depends on their classification, also based on the aroma of the oils, usually evaluated by a panel test. Nowadays, a reliable analytical method is still needed to evaluate the volatile organic compounds (VOCs) and support the standard panel test method. To date, the use of HS-SPME sampling coupled to GC-MS is generally accepted for the analysis of VOCs in VOOs. However, VOO is a challenging matrix due to the simultaneous presence of: i) compounds at ppm and ppb concentrations; ii) molecules belonging to different chemical classes and iii) analytes with a wide range of molecular mass. Therefore, HS-SPME-GC-MS quantitation based upon the use of external standard method or of only a single internal standard (ISTD) for data normalization in an internal standard method, may be troublesome. In this work a multiple internal standard normalization is proposed to overcome these problems and improving quantitation of VOO-VOCs. As many as 11 ISTDs were used for quantitation of 71 VOCs. For each of them the most suitable ISTD was selected and a good linearity in a wide range of calibration was obtained. Except for E-2-hexenal, without ISTD or with an unsuitable ISTD, the linear range of calibration was narrower with respect to that obtained by a suitable ISTD, confirming the usefulness of multiple internal standard normalization for the correct quantitation of VOCs profile in VOOs. The method was validated for 71 VOCs, and then applied to a series of lampante virgin olive oils and extra virgin olive oils. In light of our results, we propose the application of this analytical approach for routine quantitative analyses and to support sensorial analysis for the evaluation of positive and negative VOOs attributes. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Use of solid-phase microextraction (SPME) for the determination of methadone and EDDP in human hair by GC-MS.

    Science.gov (United States)

    Lucas, A C; Bermejo, A M; Tabernero, M J; Fernández, P; Strano-Rossi, S

    2000-01-10

    Solid-phase microextraction (SPME) is a new extraction technique with many advantages: small sample volume, simplicity, quickness and solvent-free. It is mainly applied to environmental analysis, but is also useful for the extraction of drugs from biological samples. In this paper the use of SPME is proposed for the determination of methadone and its main metabolite EDDP in hair by GC-MS. The hair samples were washed, cut into 1-mm segments, and incubated with Pronase E for 12 h. A 100-micron polydimethylsiloxane (PDMS) film fibre was submerged for 30 min in a diluted solution of the hydrolysis liquid (1:4 with borax buffer) containing methadone-d3 and EDDP-d3 as internal standards. Once the microextraction was concluded the fibre was directly inserted into the CG injection port. Linearity was found for methadone and EDDP in the range studied, 1.0-50 ng/mg hair, with correlation coefficients higher than 0.99. Interassay relative standard deviation (R.S.D) was determined to be less than 13.30% for methadone and less than 8.94% for EDDP, at 3.0 and 30.0 ng/mg. Analytical recoveries were close to 100% for both compounds on spiked samples. The method was applied to the analysis of real hair samples from eight patients of a methadone maintenance programme. The concentration of methadone in hair ranged from 2.45 to 78.10 ng/mg, and for EDDP from 0.98 to 7.76 ng/mg of hair.

  1. Analysis of volatile compounds of Ilex paraguariensis A. St. - Hil. and its main adulterating species Ilex theizans Mart. ex Reissek and Ilex dumosa Reissek Análise de compostos voláteis de Ilex paraguariensis A. St. - Hil. e suas principais espécies adulterantes Ilex theizans Mart. ex Reissek e Ilex dumosa Reissek

    Directory of Open Access Journals (Sweden)

    Rogério Marcos Dallago

    2011-12-01

    Full Text Available The adulteration of the product Ilex paraguariensis with other Ilex species is a mAjor problem for maté tea producers. In this work, three species of Ilex were evaluated for their volatile composition by headspace solid phase microextraction coupled to gas chromatography and mass spectrum detector (HS-SPME/GC-MS. The adulterating species I. dumnosa and I. theizans Mart. ex Reissek presented a different profile of volatile organic compounds when compared to I. paraguariensis. Aldehydes methyl-butanal, pentanal, hexanal, heptanal and nonanal were detected only in the adulterating species. This result suggests that such compounds are potential chemical markers for identification of adulteration and quality analysis of products based on Ilex paraguariensis.A adulteração do produto Ilex paraguariensis com outras espécies de Ilex é um dos principais problemas dos produtores de erva-mate. Neste trabalho, três espécies de Ilex foram avaliadas quanto à sua composição volátil por microextração em fase sólida acoplada à cromatografia gasosa e detector de espectro de massas (HS-SPME/GC-MS. As espécies adulterantes I. dumnosa e I. theizans Mart. ex Reissek apresentaram um perfil diferente de compostos orgânicos voláteis, quando comparadas com a I. paraguariensis. Os aldeídos metil-butanal, pentanal, hexanal, heptanal e nonanal foram detectados apenas nas espécies adulterantes. Esse resultado sugere que esses compostos químicos são marcadores potenciais para a identificação de adulteração e análise da qualidade dos produtos à base de Ilex paraguariensis.

  2. Lab-In-Syringe automation of stirring-assisted room-temperature headspace extraction coupled online to gas chromatography with flame ionization detection for determination of benzene, toluene, ethylbenzene, and xylenes in surface waters.

    Science.gov (United States)

    Horstkotte, Burkhard; Lopez de Los Mozos Atochero, Natalia; Solich, Petr

    2018-06-22

    Online coupling of Lab-In-Syringe automated headspace extraction to gas chromatography has been studied. The developed methodology was successfully applied to surface water analysis using benzene, toluene, ethylbenzene, and xylenes as model analytes. The extraction system consisted of an automatic syringe pump with a 5 mL syringe into which all solutions and air for headspace formation were aspirated. The syringe piston featured a longitudinal channel, which allowed connecting the syringe void directly to a gas chromatograph with flame ionization detector via a transfer capillary. Gas injection was achieved via opening a computer-controlled pinch valve and compressing the headspace, upon which separation was initialized. Extractions were performed at room temperature; yet sensitivity comparable to previous work was obtained by high headspace to sample ratio V HS /V Sample of 1.6:1 and injection of about 77% of the headspace. Assistance by in-syringe magnetic stirring yielded an about threefold increase in extraction efficiency. Interferences were compensated by using chlorobenzene as an internal standard. Syringe cleaning and extraction lasting over 10 min was carried out in parallel to the chromatographic run enabling a time of analysis of <19 min. Excellent peak area repeatabilities with RSD of <4% when omitting and <2% RSD when using internal standard corrections on 100 μg L -1 level were achieved. An average recovery of 97.7% and limit of detection of 1-2 μg L -1 were obtained in analyses of surface water. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Kainari, a Unique Greek Traditional Herbal Tea, from the Island of Lesvos: Chemical Analysis and Antioxidant and Antimicrobial Properties

    Directory of Open Access Journals (Sweden)

    Evangelia Bampali

    2018-01-01

    Full Text Available The chemical composition, as well as the total phenolic content (TPC and the potential antioxidant and antimicrobial activity, of three Kainari-herbal tea samples from different areas of Lesvos Island (Greece was evaluated. The rich aroma of the mixtures was studied through GC-MS, as well as through Headspace Solid-Phase Microextraction (HS-SPME/GC-MS analyses. Cinnamon, clove, nutmeg, pepper, and ginger were identified as main ingredients, while, throughout the chemical analysis of the volatiles of one selected sample, several secondary metabolites have been isolated and identified on the basis of GC-MS as well as spectral evidence as eugenol, cinnamic aldehyde and myristicin, cinnamyl alcohol, alpha-terpinyl acetate, and β-caryophyllene. Furthermore, two food dyes, azorubine and amaranth, were also isolated and identified from the infusions. The total phenolic content was estimated and the free radical scavenging activity was determined by DPPH and ABTS assays and the antimicrobial activity of the extracts was tested showing a very interesting profile against all the assayed microorganisms. Due to its very pleasant aroma and taste properties as well as to its bioactivities, Kainari-herbal tea could be further proposed as functional beverage.

  4. Characterization of Fish Sauce Aroma Impact Compounds Using GC-MS, SPME-Osme-GCO, and Stevens' Power Law Exponents

    Science.gov (United States)

    The objectives of this study were to characterize volatile compounds and to determine the characteristic aromas associated with impact compounds in 4 fish sauces using solid-phase micro-extraction, gas chromatography-mass spectrometry, Osme, and gas chromatography olfactometry (SPME-Osme-GCO) couple...

  5. A new method for the determination of short-chain fatty acids from the aliphatic series in wines by headspace solid-phase microextraction-gas chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Olivero, Sergio J Pérez; Trujillo, Juan P Pérez

    2011-06-24

    A new analytical method for the determination of nine short-chain fatty acids (acetic, propionic, isobutyric, butyric, isovaleric, 2-methylbutyric, hexanoic, octanoic and decanoic acids) in wines using the automated HS/SPME-GC-ITMS technique was developed and optimised. Five different SPME fibers were tested and the influence of different factors such as temperature and time of extraction, temperature and time of desorption, pH, strength ionic, tannins, anthocyans, SO(2), sugar and ethanol content were studied and optimised using model solutions. Some analytes showed matrix effect so a study of recoveries was performed. The proposed HS/SPME-GC-ITMS method, that covers the concentration range of the different analytes in wines, showed wide linear ranges, values of repeatability and reproducibility lower than 4.0% of RSD and detection limits between 3 and 257 μgL(-1), lower than the olfactory thresholds. The optimised method is a suitable technique for the quantitative analysis of short-chain fatty acids from the aliphatic series in real samples of white, rose and red wines. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Determination of the solubility of low volatility liquid organic compounds in water using volatile-tracer assisted headspace gas chromatography.

    Science.gov (United States)

    Zhang, Shu-Xin; Chai, Xin-Sheng; Barnes, Donald G

    2016-02-26

    This study reports a new headspace gas chromatographic method (HS-GC) for the determination of water solubility of low volatility liquid organic compounds (LVLOs). The HS-GC analysis was performed on a set of aqueous solutions containing a range of concentrations of toluene-spiked (as a tracer) LVLOs, from under-saturation to over-saturation. A plot of the toluene tracer GC signal vs. the concentration of the LVLO results in two lines of different slopes that intersect at the concentration corresponding to the compound's solubility in water. The results showed that the HS-GC method has good precision (RSD waters of environmental and biological systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Field-based Evaluation of a Novel SPME-GC-MS Method for Investigation of Below-ground Interaction between Brassica Roots and Larvae of Cabbage Root Fly, Delia radicum L.

    Science.gov (United States)

    Deasy, William; Shepherd, Tom; Alexander, Colin J; Birch, A Nicholas E; Evans, K Andrew

    2016-11-01

    Collection of volatiles from plant roots poses technical challenges due to difficulties accessing the soil environment without damaging the roots. To validate a new non-invasive method for passive sampling of root volatiles in situ, from plants grown under field conditions, using solid phase micro-extraction (SPME). SPME fibres were inserted into perforated polytetrafluoroethene (PTFE) tubes positioned in the soil next to broccoli plants for collection of root volatiles pre- and post-infestation with Delia radicum larvae. After sample analysis by gas chromatography-mass spectrometry (GC-MS), principal component analysis (PCA) was applied to determine differences in the profiles of volatiles between samples. GC-MS analysis revealed that this method can detect temporal changes in root volatiles emitted before and after Delia radicum damage. PCA showed that samples collected pre- and post-infestation were compositionally different due to the presence of root volatiles induced by D. radicum feeding. Sulphur containing compounds, in particular, accounted for the differences observed. Root volatiles emission patterns post-infestation are thought to follow the feeding and developmental progress of larvae. This study shows that volatiles released by broccoli roots can be collected in situ using SPME fibres within perforated PTFE tubes under field conditions. Plants damaged by Delia radicum larvae could be distinguished from plants sampled pre-infestation and soil controls on the basis of larval feeding-induced sulphur-containing volatiles. These results show that this new method is a powerful tool for non-invasive sampling of root volatiles below-ground. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Oxidative Stress Biomarkers in Exhaled Breath of Workers Exposed to Crystalline Silica Dust by SPME-GC-MS.

    Science.gov (United States)

    Jalali, Mahdi; Zare Sakhvidi, Mohammad Javad; Bahrami, Abdulrahman; Berijani, Nima; Mahjub, Hussein

    2016-01-01

    Silicosis is considered an oxidative stress related disease that can lead to the development of lung cancer. In this study, our purpose was to analysis of volatile organic compounds (VOCs) in the exhaled breath of workers exposed to silica containing dust and compare peak area of these compounds with silicosis patients and healthy volunteers (smokers and nonsmokers) groups. In this cross sectional case-control study, the exhaled breath of 69 subjects including workers exposed to silica (n=20), silicosis patient (n=4), healthy non-smoker (n=20) and healthy smoker (n=25) were analyzed. We collected breath samples using 3-liter Tedlar bags. The VOCs were extracted with solid phase micro-extraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). Personal exposure intensity was measured according to NIOSH 7601 method. Respiratory parameters were measured using spirometry. Seventy percent and 100% of the exposures to crystalline silica dust exceeded from 8 h TWA ACGIH TLVs in case and positive control groups, respectively. A significant negative correlation was found between dust exposure intensity and FEV1/FVC when exposure and positive control groups were studied in a group (r2=-0.601, P<0.001). Totally, forty VOCs were found in all exhaled breath samples. Among the VOCs, the mean of peak area acetaldehyde, hexanal, nonanal, decane, pentad cane, 2-propanol and 3-hydroxy-2-butanone were higher in exhaled breath of the workers exposed to silica and silicosis patient compared to the healthy smoker and nonsmoker controls. In some cases the difference was significant (P<0.05). The analysis of some VOCs in exhaled breath of subjects is appropriate biomarker to determine of exposure to silica.

  9. The potential of head-space gas chromatography for VLE measurements

    International Nuclear Information System (INIS)

    Luis, Patricia; Wouters, Christine; Sweygers, Nick; Creemers, Claude; Van der Bruggen, Bart

    2012-01-01

    Highlights: ► HS-GC is a potential technique to obtain VLE data in a high throughput scenario. ► We applied HS-GC and evaluate the main issues to consider. ► Four azeotropic mixtures of industrial interest are studied. ► The thermodynamic analysis of VLE shows the strong non-ideality of the mixtures. - Abstract: Head-space gas chromatography (HS-GC) is thought to allow the performance of (vapour + liquid) equilibrium (VLE) measurements in a fast and automated way. However, two decades after the first applications of HS-GC for this purpose, the potential of this technique is not fully developed yet. Measurements of isothermal VLE and activity coefficients of mixtures can be obtained in a high throughput scenario. However, several considerations have to be taken into account before starting the analysis, such as the equilibration time or the minimum sample volume and the GC response factors. These aspects can strongly influence on the validity of the results and should therefore be determined for each mixture. In this paper, four azeotropic mixtures of interest in the pharmaceutical and chemical industry, i.e., (ethylacetate + water), which forms a heterogeneous azeotrope, (ethylacetate + isooctane), (acetonitrile + toluene) and the ternary mixture (acetonitrile + toluene + tetrahydrofuran), are considered to show the potential of HS-GC for VLE measurements. The thermodynamic analysis of VLE data leads to activity coefficients for the mixtures at (35, 50, and 70) °C. In addition, the experimental data are compared with thermodynamic models and data from the literature, when available.

  10. Determination of benzene, toluene, ethylbenzene and xylene in field and laboratory by means of cold fiber SPME equipped with thermoelectric cooler and GC/FID method

    Directory of Open Access Journals (Sweden)

    Tajik Leila

    2017-09-01

    Full Text Available A simple and effective cooling device based on a thermoelectric cooler was applied to cool the SPME fiber. The device was used for quantitative extraction of aromatic hydrocarbons in the air. Several factors such as coating temperature, extraction temperature and relative humidity in the laboratory setting were optimized. Comparison of the results between the cold fiber SPME (CF-SPME and NIOSH 1501 method on standard test atmosphere indicated a satisfactory agreement. The CF-SPME and SPME method were also compared. The results revealed that CF-SPME has the most appropriate outcome for the extraction of aromatic hydrocarbons from the ambient air. The cold fiber SPME technique showed good results for several validation parameters. Under the optimized conditions, the limits of detection (LOD and the limits of quantification (LOQ ranged from 0.00019 to 0.00033 and 0.0006 to 0.001 ng ml−1, respectively. The intra-day relative standard deviation (RSD showed ranging from 4.8 to 10.5%.

  11. Aplicação de SPME (Solid Phase Micro-Extraction na análise de águas potáveis de três localidades do estado de São Paulo

    Directory of Open Access Journals (Sweden)

    Valente Antonio Luiz Pires

    1998-01-01

    Full Text Available The technique of solid phase microextraction (SPME was used for the extraction of halogenated contaminants of water samples from three cities of the State of São Paulo and the extracts were submitted to gas chromatographic analysis with electron capture detection (GC-ECD. In the samples of water collected at the city of São Paulo the detected level of trihalomethanes (THM expressed as the sum of chloroform, dibromochloromethane and dichlorobromomethane, were higher than the permissible limit established by the Brazilian regulation. In the samples collected at the two other cities the level of any of the three THM remained below the sensitivity of the ECD.

  12. Comparação entre injeção na coluna ("on-column" e headspace dinâmico na determinação de benzeno, tolueno e xilenos (BTX em amostras de água

    Directory of Open Access Journals (Sweden)

    Gobato Elaine A. A. F.

    2001-01-01

    Full Text Available The analysis of water samples containing volatile organic compounds has become an important task in analytical chemistry. Gas chromatography has been widely used for the analysis of volatile organic compounds in water. The headspace analysis shows as a principal characteristic the possibility of determination of the volatile components in drinking water. Benzene, Toluene and Xylene (BTX are important compounds usually present in drinking water, from contamination by petroleum derivatives. Since they are toxic compounds even when present in low concentration levels, their determination is important in order to define the quality of the water. The sampling technique using headspace, coupled with gas chromatography as the separation method, showed to be suitable for BTX analysis in several samples at the mug/L (ppb level.

  13. Head Space Solid Phase Micro-Extraction (HS - SPME of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636

    Directory of Open Access Journals (Sweden)

    Eunice Valduga

    2010-12-01

    Full Text Available The aim of the present study was the assessment of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636 using methyl and ethyl ricinoleate, ricinoleic acid and castor oil as precursors. The analysis of the volatile organic compounds was carried out using Head Space Solid Phase Micro-Extraction (HS - SPME. Factorial experimental design was used for investigating extraction conditions, verifying stirring rate (0-400 rpm, temperature (25-60 ºC, extraction time (10-30 minutes, and sample volume (2-3 mL. The identification of volatile organic compounds was carried out by Gas Chromatography with Mass Spectrum Detector (GC/MSD. The conditions that resulted in maximum extraction were: 60 ºC, 10 minutes extraction, no stirring, sample volume of 2.0 mL, and addition of saturated KCl (1:10 v/v. In the bio-production of volatile organic compounds the effect of stirring rate (120-200 rpm, temperature (23-33 ºC, pH (4.0-8.0, precursor concentration (0.02-0.1%, mannitol (0-6%, and asparagine concentration (0-0.2% was investigated. The bio-production at 28 ºC, 160 rpm, pH 6,0 and with the addition of 0.02% ricinoleic acid to the medium yielded the highest production of VOCs, identified as 1,4-butanediol, 1,2,2-trimethylciclopropilamine, beta-ionone; 2,3-butanodione, pentanal, tetradecane, 2-isononenal, 4-octen-3-one, propanoic acid, and octadecane.

  14. An approach to determination of phenolic compounds in seawater using SPME-GC-MS based on SWCNTs coating

    Science.gov (United States)

    Zhu, Jia; Wang, Ying; Zeng, Lin

    2016-08-01

    Phenolic compounds have become one kind of the important pollutants of the marine environment. Single-walled Carbon nanotubes, as one-dimensional nano materials, have light weight and perfect hexagonal structure of connections, with many unusual mechanical, chemical and electrical properties. In recent years, with the research of carbon nanotubes and other nano materials, the application prospect is also constantly discussed. In this paper, homemade single-walled carbon nanotubes (SWCNTs) coating was used for establishing an analytical approach to the determination of five kinds of phenolic compounds in seawater using SPME-GC-MS. Optimal conditions: After saturation was conducted with NaCl, and pH was adjusted to 2.0 with H2SO4, the extract was immersed in a water bath at 40°C for GC-MS determination through 40-min agitating extraction at 500 rmin-1 and 3-min desorption at 280°C. The liniearities ranged between 0.01-100 μg L-1, and the determination limits ranged between 1.5-10 ng L-1. The relative standard deviation (RSD, n = 5) was less than 6.5%. For the phenolic compounds obtained from the spiked recovery test for actual seawater samples, the rates of recovery were 87.5%-101.7%, and the RSDs were less than 8.8%, which met the requirements of determination. Due to its simplicity, high efficiency and low consumption, this approach is suitable for the analysis of trace amounts of phenolic compounds in marine waters.

  15. Usefulness of a PARAFAC decomposition in the fiber selection procedure to determine chlorophenols by means SPME-GC-MS.

    Science.gov (United States)

    Morales, Rocío; Cruz Ortiz, M; Sarabia, Luis A

    2012-05-01

    In this work, a procedure based on solid-phase microextraction and gas chromatography coupled with mass spectrometry is proposed to determine chlorophenols in water without derivatization. The following chlorophenols are studied: 2,4-dichlorophenol; 2,4,6-trichlorophenol; 2,3,4,6-tetrachlorophenol and pentachlorophenol. Three kinds of SPME fibers, polyacrylate, polydimethylsiloxane, and polydimethylsiloxane/divinylbenzene are compared to identify the most suitable one for the extraction process on the basis of two criteria: (a) to select the equilibrium time studying the kinetics of the extraction, and (b) to obtain the best values of the figures of merit. In both cases, a three-way PARAllel FACtor analysis decomposition is used. For the first step, the three-way experimental data are arranged as follows: if I extraction times are considered, the tensor of data, X, of dimensions I × J × K is generated by concatenating the I matrices formed by the abundances of the J m/z ions recorded in K elution times around the retention time for each chlorophenol. The second-order property of PARAFAC (or PARAFAC2) assesses the unequivocal identification of each chlorophenol, as consequence, the loadings in the first mode estimated by the PARAFAC decomposition are the kinetic profile. For the second step, a calibration based on a PARAFAC decomposition is used for each fiber. The best figures of merit were obtained with PDMS/DVB fiber. The values of decision limit, CCα, achieved are between 0.29 and 0.67 μg L(-1) for the four chlorophenols. The accuracy (trueness and precision) of the procedure was assessed. This procedure has been applied to river water samples.

  16. Authenticity of raspberry flavor in food products using SPME-chiral-GC-MS

    DEFF Research Database (Denmark)

    Hansen, Anne-Mette Sølvbjerg; Frandsen, Henrik Lauritz; Fromberg, Arvid

    2015-01-01

    A fast and simple method for authenticating raspberry flavors from food products was developed. The two enantiomers of the compound (E)-α-ionone from raspberry flavor were separated on a chiral gas chromatographic column. Based on the ratio of these two enantiomers the naturalness of a raspberry...... flavor can be evaluated due to the fact that a natural flavor will consist almost exclusively of the R enantiomer, while a chemical synthesis of the same compound will result in a racemic mixture. 27 food products containing raspberry flavors where investigated using SPME-chiral-GC-MS. We found raspberry...... distribution of the R and S isomer. Two products were labelled to contain natural raspberry flavors but were found to contain almost equal amounts of both enantiomers indicating a presence of synthetic raspberry flavors only. Additionally, two products labelled to contain both raspberry juice and flavor showed...

  17. Use of solid phase microextraction (SPME) for profiling the volatile metabolites produced by Glomerella cingulata.

    Science.gov (United States)

    Miyazawa, Mitsuo; Kimura, Minako; Yabe, Yoshito; Tsukamoto, Daisuke; Sakamoto, Masaya; Horibe, Isao; Okuno, Yoshiharu

    2008-01-01

    The profile of volatile organic compounds (VOCs) released from Glomerella cingulata using solid phase microextraction (SPME) with different fibers, Polydimethylsiloxane (PDMS), Polydimethylsiloxane/Divinylbenzene (PDMS/DVB), Carboxen/Polydimethylsiloxane (CAR/PDMS) and Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS), was investigated. C4-C6 aliphatic alcohols were the predominant fraction of VOCs isolated by CAR/PDMS fiber. Sesquiterpene hydrocarbons represented 20.3% of VOCs isolated by PDMS fiber. During the growth phase, Ochracin was produced in the large majority of VOCs. 3-Methylbutanol and phenylethyl alcohol were found in the log phase of it. Alcohols were found in cultures of higher age, while sesquiterpenes were found to be characteristic of initial growth stage of G. cingulata.

  18. Flight attraction of Spodoptera littoralis (Lepidoptera, Noctuidae to cotton headspace and synthetic volatile blends

    Directory of Open Access Journals (Sweden)

    Felipe eBorrero-Echeverry

    2015-06-01

    Full Text Available The insect olfactory system discriminates odor signals of different biological relevance, which drive innate behavior. Identification of stimuli that trigger upwind flight attraction towards host plants is a current challenge, and is essential in developing new, sustainable plant protection methods, and for furthering our understanding of plant-insect interactions. Using behavioral, analytical and electrophysiological studies, we here show that both females and males of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera, Noctuidae, use blends of volatile compounds to locate their host plant, cotton, Gossypium hirsutum (Malvales, Malvaceae. Female S. littoralis were engaged in upwind orientation flight in a wind tunnel when headspace collected from cotton plants was delivered through a piezoelectric sprayer. Although males took off towards cotton headspace significantly fewer males than females flew upwind towards the sprayed headspace. Subsequent assays with antennally active synthetic compounds revealed that a blend of nonanal, (Z-3 hexenyl acetate, (E-β-ocimene, and (R-(+-limonene was as attractive as cotton headspace to females and more attractive to males. DMNT and (R-(--linalool, both known plant defense compounds may have reduced the flight attraction of both females and males; more moths were attracted to blends without these two compounds. Our findings provide a platform for further investigations on host plant signals mediating innate behavior, and for the development of novel insect plant protection strategies against S. littoralis.

  19. Determination of carboxyl groups in wood fibers by headspace gas chromatography

    Science.gov (United States)

    X.-S. Chai; Q.X. Hou; J.Y. Zhu; S.-L. Chen; S.F. Wang; L. Lucia

    2003-01-01

    The phase reaction conversion (PRC) headspace gas chromatographic (HSGC) technique was employed to develop a method for the determination of the content of carboxyl groups in wood fibers. Acid treatment of the wood fibers using hydrochloric was applied to convert carboxyl groups to carboxyl acids. Bicarbonate solution is then used to react with carboxyl acids on the...

  20. Tank 241-B-103 headspace gas and vapor characterization results for samples collected in February 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  1. Tank 241-BX-104 headspace gas and vapor characterization results for samples collected in December 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  2. Measurement of water absorption capacity in wheat flour by a headspace gas chromatographic technique.

    Science.gov (United States)

    Xie, Wei-Qi; Yu, Kong-Xian; Gong, Yi-Xian

    2018-04-17

    The purpose of this work is to introduce a new method for quantitatively analyzing water absorption capacity in wheat flour by a headspace gas chromatographic technique. This headspace gas chromatographic technique was based on measuring the water vapor released from a series of wheat flour samples with different contents of water addition. According to the different trends between the vapor and wheat flour phase before and after the water absorption capacity in wheat flour, a turning point (corresponding to water absorption capacity in wheat flour) can be obtained by fitting the data of the water gas chromatography peak area from different wheat flour samples. The data showed that the phase equilibrium in the vial can be achieved in 25 min at desired temperature (35°C). The relative standard deviation of the reaction headspace gas chromatographic technique in water absorption capacity determination was within 3.48%, the relative differences has been determined by comparing the water absorption capacity obtained from this new analytical technique with the data from the reference technique (i.e., the filtration method), which are less than 8.92%. The new headspace gas chromatographic method is automated, accurate and be a reliable tool for quantifying water absorption capacity in wheat flour in both laboratory research and mill applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Haahr, Anne-Mette; Jensen, Benny

    1999-01-01

    A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were...

  4. Tank 241-U-203 headspace gas and vapor characterization results for samples collected in August 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  5. Tank 241-C-106 headspace gas and vapor characterization results for samples collected in February 1994

    International Nuclear Information System (INIS)

    Hackaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  6. Tank 241-S-111 headspace gas and vapor characterization results for samples collected in March 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  7. Tank 241-U-103 headspace gas and vapor characterization results for samples collected in February 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  8. Tank 241-SX-106 headspace gas and vapor characterization results for samples collected in March 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  9. Tank 241-TX-105 headspace gas and vapor characterization results for samples collected in December 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  10. Tank 241-C-102 headspace gas and vapor characterization results for samples collected in August 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  11. Tank 241-BY-112 headspace gas and vapor characterization results for samples collected in November 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  12. Tank 241-T-111 headspace gas and vapor characterization results for samples collected in January 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  13. Tank 241-SX-103 headspace gas and vapor characterization results for samples collected in March 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  14. Tank 241-TY-104 headspace gas and vapor characterization results for samples collected in April 1995

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  15. Tank 241-C-110 headspace gas and vapor characterization results for samples collected in August 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  16. Tank 241-C-101 headspace gas and vapor characterization results for samples collected in September 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  17. Tank 241-C-107 headspace gas and vapor characterization results for samples collected in September 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  18. Tank 241-C-104 headspace gas and vapor characterization results for samples collected in March 1994

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Bratzel, D.R.

    1995-01-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  19. An analytical method for trifluoroacetic Acid in water and air samples using headspace gas chromatographic determination of the methyl ester.

    Science.gov (United States)

    Zehavi, D; Seiber, J N

    1996-10-01

    An analytical method has been developed for the determination of trace levels of trifluoroacetic acid (TFA), an atmospheric breakdown product of several of the hydrofluorocarbon (HFC) and hydrochlorofluorocarbon (HCFC) replacements for the chlorofluorocarbon (CFC) refrigerants, in water and air. TFA is derivatized to the volatile methyl trifluoroacetate (MTFA) and determined by automated headspace gas chromatography (HSGC) with electron-capture detection or manual HSGC using GC/MS in the selected ion monitoring (SIM) mode. The method is based on the reaction of an aqueous sample containing TFA with dimethyl sulfate (DMS) in concentrated sulfuric acid in a sealed headspace vial under conditions favoring distribution of MTFA to the vapor phase. Water samples are prepared by evaporative concentration, during which TFA is retained as the anion, followed by extraction with diethyl ether of the acidified sample and then back-extraction of TFA (as the anion) in aqueous bicarbonate solution. The extraction step is required for samples with a relatively high background of other salts and organic materials. Air samples are collected in sodium bicarbonate-glycerin-coated glass denuder tubes and prepared by rinsing the denuder contents with water to form an aqueous sample for derivatization and analysis. Recoveries of TFA from spiked water, with and without evaporative concentration, and from spiked air were quantitative, with estimated detection limits of 10 ng/mL (unconcentrated) and 25 pg/mL (concentrated 250 mL:1 mL) for water and 1 ng/m(3) (72 h at 5 L/min) for air. Several environmental air, fogwater, rainwater, and surface water samples were successfully analyzed; many showed the presence of TFA.

  20. Headspace volume and percentage of carbon monoxide affects carboxymyoglobin layer development of modified atmosphere packaged beef steaks.

    Science.gov (United States)

    Raines, Christopher R; Hunt, Melvin C

    2010-01-01

    Carboxymyoglobin (COMb) development of beef Longissimus lumborum as related to molecular CO availability and package headspace volume was evaluated. Steaks from six pairs of USDA Select strip loins were packaged in modified atmosphere packages with 0.2%, 0.4%, or 0.8% CO and 30% CO(2) and balanced with N(2) to obtain meat-to-gas ratios of 0.4, 0.7, and 1.1, and CO molar concentrations of 0.07, 0.10, and 0.20 mMol. Steak redness (CIE a*), COMb layer thickness, percentage of CO in the headspace, visual display color, and bloom intensity scores were evaluated 4 and 7 d after packaging. Greater concentration of CO in a smaller headspace resulted in a thicker COMb layer compared with lesser concentration of CO in a larger headspace, regardless of moles CO available. The combined effects of concentration of CO and headspace v