The world's leading PTR-MS company

Ultra-Sensitive Real-Time Trace Gas Analyzers  •  Modular TOF-MS for Research & OEM

Navigation

You are here

Scientific Articles - PTR-MS Bibliography

Welcome to the new IONICON scientific articles database!

Publications

Found 47 results
[ Title(Asc)] Year
Filters: Author is Hansel, Armin  [Clear All Filters]
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 
X
[Kreuzwieser2002] Kreuzwieser, J., M. Graus, A. Wisthaler, A. Hansel, H. Rennenberg, and JÖRG-PETER. SCHNITZLER, "Xylem-transported glucose as an additional carbon source for leaf isoprene formation in Quercus robur", New Phytologist, vol. 156, no. 2: Wiley Online Library, pp. 171–178, 2002.
Link: http://onlinelibrary.wiley.com/doi/10.1046/j.1469-8137.2002.00516.x/full
Abstract
In order to test whether xylem-transported carbohydrates are a potential source for isoprene biosynthesis, [U- 13 C]-labelled α- d -glucose was fed via cut ends of stems into the xylem of Quercus robur seedlings and the incorporation of 13 C into isoprene emitted was studied. Emission of 13 C-labelled isoprene was monitored in real time by proton-transfer-reaction mass spectrometry (PTR-MS). A rapid incorporation of 13 C from xylem-fed glucose into single (mass 70) and double (mass 71) 13 C-labelled isoprene molecules was observed after a lag phase of approx. 5–10 min. This incorporation was temperature dependent and was highest (up to 13% 13 C of total carbon emitted as isoprene) at the temperature optimum of isoprene emission (40–42°C), when net assimilation was strongly reduced.   Fast dark-to-light transitions led to a strong single or double 13 C-labelling of isoprene from xylem-fed [U-13C]glucose. During a period of 10–15 min up to 86% of all isoprene molecules became single or double 13 C-labelled, resulting in a 13 C-portion of up to 27% of total carbon emitted as isoprene.   The results provide evidence that xylem-transported glucose or its degradation products can potentially be used as additional precursors for isoprene biosynthesis and that this carbon source becomes more important under conditions of limited photosynthesis.
V
[Fall1999] Fall, R., T. Karl, A. Hansel, A. Jordan, and W. Lindinger, "Volatile organic compounds emitted after leaf wounding: on-line analysis by proton-transfer-reaction mass spectrometry", Journal of Geophysical Research, vol. 104, no. D13: American Geophysical Union, pp. 15963–15, 1999.
Link: http://www.agu.org/pubs/crossref/1999/1999JD900144.shtml
Abstract
Volatile organic compounds (VOCs) released from vegetation, including wound-induced VOCs, can have important effects on atmospheric chemistry. The analytical methods for measuring wound-induced VOCs, especially the hexenal family of VOCs (hexenals, hexenols, and hexenyl esters), are complicated by their chemical instability and the transient nature of their formation after leaf and stem wounding. Here we demonstrate that formation and emission of hexenal family compounds can be monitored on-line using proton-transfer-reaction mass spectrometry (PTR-MS), avoiding the need for preconcentration or chromatography. These measurements allow direct analysis of the rapid emission of the parent compound, (Z)-3-hexenal, within 1–2 s of wounding of aspen leaves and then its disappearance and the appearance of its metabolites including (E)-2-hexenal, hexenols, and hexenyl acetates. Similar results were seen in wounded beech leaves and clover. The emission of hexenal family compounds was proportional to the extent of wounding, was not dependent on light, occurred in attached or detached leaves, and was greatly enhanced as detached leaves dried out. Emission of (Z)-3-hexenal from detached drying aspen leaves averaged 500 μg C g−1 (dry leaf weight). Leaf wound compounds were not emitted in a nitrogen atmosphere but were released within seconds of reintroduction of oxygen; this indicates that there are not large pools of hexenyl compounds in leaves. The PTR-MS method also allows the simultaneous detection of less abundant hexanal family VOCs including hexanal, hexanol, and hexyl acetate and VOCs formed in the light (isoprene) or during anoxia (acetaldehyde). PTR-MS may be a useful tool for the analysis of VOC emissions resulting from grazing, herbivory, and other physical damage to vegetation, from harvesting of crops, and from senescing leaves.
T
[Graus2004] Graus, M., JÖRG-PETER. SCHNITZLER, A. Hansel, C. Cojocariu, H. Rennenberg, A. Wisthaler, and J. Kreuzwieser, "Transient release of oxygenated volatile organic compounds during light-dark transitions in grey poplar leaves", Plant Physiology, vol. 135, no. 4: American Society of Plant Biologists, pp. 1967–1975, 2004.
Link: http://www.plantphysiology.org/content/135/4/1967.short
Abstract
In this study, we investigated the prompt release of acetaldehyde and other oxygenated volatile organic compounds (VOCs) from leaves of Grey poplar [Populus x canescens (Aiton) Smith] following light-dark transitions. Mass scans utilizing the extremely fast and sensitive proton transfer reaction-mass spectrometry technique revealed the following temporal pattern after light-dark transitions: hexenal was emitted first, followed by acetaldehyde and other C6-VOCs. Under anoxic conditions, acetaldehyde was the only compound released after switching off the light. This clearly indicated that hexenal and other C6-VOCs were released from the lipoxygenase reaction taking place during light-dark transitions under aerobic conditions. Experiments with enzyme inhibitors that artificially increased cytosolic pyruvate demonstrated that the acetaldehyde burst after light-dark transition could not be explained by the recently suggested pyruvate overflow mechanism. The simulation of light fleck situations in the canopy by exposing leaves to alternating light-dark and dark-light transitions or fast changes from high to low photosynthetic photon flux density showed that this process is of minor importance for acetaldehyde emission into the Earth's atmosphere.
[Karl2003b] Karl, T., A. Hansel, T. Märk, W. Lindinger, and D. Hoffmann, "Trace gas monitoring at the Mauna Loa Baseline observatory using proton-transfer reaction mass spectrometry", International Journal of Mass Spectrometry, vol. 223: Elsevier, pp. 527–538, 2003.
Link: http://www.sciencedirect.com/science/article/pii/S1387380602008746
Abstract
Real time monitoring of volatile organic compounds (VOCs) using a Proton-Transfer Reaction Mass Spectrometer was performed at the Mauna Loa Baseline Station (19.54N, 155.58W) in March/April 2001 (March 23, 2001–April 17, 2001). Mixing ratios for methanol, acetone, acetonitrile, isoprene and methyl vinyl ketone (MVK) plus methacrolein (MACR) ranged between 0.2 and 1.8, 0.2 and 1, 0.07 and 0.2, <0.02 and 0.3, and <0.02 and 0.5 ppbv, respectively. Biomass burning plumes transported from South-East Asia and the Indian Subcontinent across the Pacific influenced part of the measurement campaign. ΔAcetonitrile/ΔCO and Δacetone/Δacetonitrile ratios in these cases were 1.5×10−3 to 2.5×10−3 and 2–5 ppbv/ppbv, respectively. Overall Asian outflow events were not as frequent during Spring 2001 as in previous years. Methanol did not show significant correlation with CO, acetonitrile, and acetone. The abundance of acetone and CO seemed to be influenced but not dominated by biomass burning and domestic biofuel emissions.
[Forkel2006] Forkel, R., O. Klemm, M. Graus, B. Rappenglück, W. R. Stockwell, W. Grabmer, A. Held, A. Hansel, and R. Steinbrecher, "Trace gas exchange and gas phase chemistry in a Norway spruce forest: A study with a coupled 1-dimensional canopy atmospheric chemistry emission model", Atmospheric Environment, vol. 40: Elsevier, pp. 28–42, 2006.
Link: http://www.sciencedirect.com/science/article/pii/S1352231006003189
Abstract
Numerical modelling is an efficient tool to investigate the role of chemical degradation of biogenic volatile organic compounds (BVOC) and the effect of dynamical processes on BVOC and product mixing ratios within and above forest canopies. The present study shows an application of the coupled canopy-chemistry model CACHE to a Norway spruce forest at the Waldstein (Fichtelgebirge, Germany). Simulated courses of temperature, trace gas mixing ratios, and fluxes are compared with measurements taken during the BEWA2000 field campaigns. The model permits the interpretation of the observed diurnal course of ozone and VOC by investigating the role of turbulent exchange, chemical formation and degradation, emission, and deposition during the course of the day. The simulation results show that BVOC fluxes into the atmosphere are 10–15% lower than the emission fluxes on branch basis due to chemical BVOC degradation within the canopy. BVOC degradation by the NO3 radical was found to occur in the lower part of the canopy also during daytime. Furthermore, the simulations strongly indicate that further research is still necessary concerning the emission and deposition of aldehydes and ketones.
S
[Seewald2010] Seewald, M. S. A., W. Singer, B. A. Knapp, I. H. Franke-Whittle, A. Hansel, and H. Insam, "Substrate-induced volatile organic compound emissions from compost-amended soils", Biology and Fertility of Soils, vol. 46: Springer-Verlag, pp. 371-382, 2010.
Link: http://dx.doi.org/10.1007/s00374-010-0445-0
Abstract
The agronomic effects of composts, mineral fertiliser and combinations thereof on chemical, biological and physiological soil properties have been studied in an 18-year field experiment. The present study aimed at tracing treatment effects by evaluating the volatile organic compound (VOC) emission of the differently treated soils: non-amended control, nitrogen fertilisation and composts (produced from organic waste and sewage sludge, respectively) in combination with nitrogen fertiliser. Microbial community structure was determined by denaturing gradient gel electrophoresis (DGGE). Aerobic and anaerobic soil VOC emission was determined after glucose amendment using proton transfer reaction–mass spectrometry (PTR-MS). After inducing VOC production by substrate (glucose) addition and at the same time reducing oxygen availability to impair degradation of the produced VOCs, we were able to differentiate among the treatments. Organic waste compost did not alter the VOC emissions compared to the untreated control, whilst sewage sludge composts and mineral fertilisation showed distinct effects. This differentiation was supported by DGGE analysis of fungal 18S rDNA fragments and confirms earlier findings on bacterial communities. Three major conclusions can be drawn: (1) VOC patterns are able to discriminate among soil treatments. (2) Sewage sludge compost and mineral fertilisation have not only the strongest impact on microbial community composition but also on VOC emission patterns, but specific tracer VOCs could not be identified. (3) Future efforts should aim at a PTR-MS-linked identification of the detected masses.
R
[Graus2006] Graus, M., A. Hansel, A. Wisthaler, C. Lindinger, R. Forkel, K. Hauff, M. Klauer, A. Pfichner, B. Rappenglück, D. Steigner, et al., "A relaxed-eddy-accumulation method for the measurement of isoprenoid canopy-fluxes using an online gas-chromatographic technique and PTR-MS simultaneously", Atmospheric Environment, vol. 40: Elsevier, pp. 43–54, 2006.
Link: http://www.sciencedirect.com/science/article/pii/S1352231006003190
Abstract
A relaxed-eddy-accumulation set-up using an online gas-chromatographic technique and proton-transfer-reaction mass spectrometry was applied to determine isoprenoid fluxes above a Norway spruce forest in July 2001/2002. The system was quality assured and its suitability for determination of canopy fluxes of isoprenoids was demonstrated. Flux measurements of oxygenated hydrocarbons failed the data quality check due to artefacts presumably arising from line and ozone-scrubber effects. Observations of turbulent fluxes of isoprenoids during the two field experiments show good agreements with primary flux data derived from enclosure measurements and modelling results using a canopy-chemistry emission model (CACHE).
[Schaub2010] Schaub, A., J. D. Blande, M. Graus, E. Oksanen, J. K. Holopainen, and A. Hansel, "Real-time monitoring of herbivore induced volatile emissions in the field.", Physiol Plant, vol. 138, no. 2: Ionicon Analytik GmbH, Technikerstrasse 21a, 6020 Innsbruck, Austria., pp. 123–133, Feb, 2010.
Link: http://dx.doi.org/10.1111/j.1399-3054.2009.01322.x
Abstract
When plants are damaged by herbivorous insects they emit a blend of volatile organic compounds (VOCs) which include a range or terpenoids and green leaf volatiles (GLVs) formed via different metabolic pathways. The precise timing of these emissions upon the onset of herbivore feeding has not been fully elucidated, and the information that is available has been mainly obtained through laboratory based studies. We investigated emissions of VOCs from Populus tremula L. xP. tremuloides Michx. during the first 20 h of feeding by Epirrita autumnata (autumnal moth) larvae in a field site. The study was conducted using Proton Transfer Reaction-Mass Spectrometry (PTR-MS) to measure emissions online, with samples collected for subsequent analysis by complementary gas chromatography-mass spectrometry for purposes of compound identification. GLV emission peaks occurred sporadically from the outset, indicating herbivore activity, while terpene emissions were induced within 16 h. We present data detailing the patterns of monoterpene (MT), GLV and sesquiterpene (SQT) emissions during the early stages of herbivore feeding showing diurnal MT and SQT emission that is correlated more with temperature than light. Peculiarities in the timing of SQT emissions prompted us to conduct a thorough characterization of the equipment used to collect VOCs and thus corroborate the accuracy of results. A laboratory based analysis of the throughput of known GLV, MT and SQT standards at different temperatures was made with PTR-MS. Enclosure temperatures of 12, 20 and 25 degrees C had little influence on the response time for dynamic measurements of a GLV or MT. However, there was a clear effect on SQT measurements. Elucidation of emission patterns in real-time is dependent upon the dynamics of cuvettes at different temperatures.
Q
[Mielke2010] Mielke, L. H., K. A. Pratt, P. B. Shepson, S. A. McLuckey, A. Wisthaler, and A. Hansel, "Quantitative determination of biogenic volatile organic compounds in the atmosphere using proton-transfer reaction linear ion trap mass spectrometry.", Anal Chem, vol. 82, no. 19: Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA., pp. 7952–7957, Oct, 2010.
Link: http://dx.doi.org/10.1021/ac1014244
Abstract
Although oxidation of biogenic volatile organic compounds (BVOCs) plays an important role in tropospheric ozone and secondary organic aerosol production, significant uncertainties remain in our understanding of the impacts of BVOCs on ozone, aerosols, and climate. To quantify BVOCs, the proton-transfer reaction linear ion trap (PTR-LIT) mass spectrometer was previously developed. The PTR-LIT represents an improvement over more traditional techniques (including the proton-transfer reaction mass spectrometer), providing the capability to directly quantify and differentiate isomeric compounds by MS/MS analysis, with better time resolution and minimal sample handling, compared to gas chromatography techniques. Herein, we present results from the first field deployment of the PTR-LIT. During the Program for Research on Oxidants: Photochemistry, Emissions and Transport (PROPHET) summer 2008 study in northern Michigan, the PTR-LIT successfully quantified isoprene, total monoterpenes, and isomeric isoprene oxidation products methyl vinyl ketone and methacrolein at sub-parts per billion (nmol/mol) levels in a complex forest atmosphere. The utility of the fast time response of the PTR-LIT was shown by the measurement of rapid changes in isoprene, methyl vinyl ketone, and methacrolein, concurrent with changing ozone mole fractions. Overall, the PTR-LIT was shown to be a viable field instrument with the necessary sensitivity, selectivity, and time response to provide detailed measurements of BVOC mole fractions in complex atmospheric samples, at trace levels.
[Brilli2012] Brilli, F., L. Hörtnagl, I. Bamberger, R. Schnitzhofer, T. M. Ruuskanen, A. Hansel, F. Loreto, and G. Wohlfahrt, "Qualitative and quantitative characterization of volatile organic compound emissions from cut grass.", Environ Sci Technol, vol. 46, no. 7: Ionicon Analytik GmbH, Eduard-Bodem-Gasse 3, 6020 Innsbruck, Austria., pp. 3859–3865, Apr, 2012.
Link: http://dx.doi.org/10.1021/es204025y
Abstract
Mechanical wounding of plants triggers the release of a blend of reactive biogenic volatile organic compounds (BVOCs). During and after mowing and harvesting of managed grasslands, significant BVOC emissions have the potential to alter the physical and chemical properties of the atmosphere and lead to ozone and aerosol formation with consequences for regional air quality. We show that the amount and composition of BVOCs emitted per unit dry weight of plant material is comparable between laboratory enclosure measurements of artificially severed grassland plant species and in situ ecosystem-scale flux measurements above a temperate mountain grassland during and after periodic mowing and harvesting. The investigated grassland ecosystem emitted annually up to 130 mg carbon m(-2) in response to cutting and drying, the largest part being consistently represented by methanol and a blend of green leaf volatiles (GLV). In addition, we report the plant species-specific emission of furfural, terpenoid-like compounds (e.g., camphor), and sesquiterpenes from cut plant material, which may be used as tracers for the presence of given plant species in the ecosystem.
P
[Wisthaler2007] Wisthaler, A., P. Strøm-Tejsen, L. Fang, T. J. Arnaud, A. Hansel, T. D. Maerk, and D. P. Wyon, "PTR-MS assessment of photocatalytic and sorption-based purification of recirculated cabin air during simulated 7-h flights with high passenger density.", Environ Sci Technol, vol. 41, no. 1: Institut fuer Ionenphysik, Leopold-Franzens- Universitaet Innsbruck, A-6020 Innsbruck, Austria. armin.wisthaler@uibk.ac.at, pp. 229–234, Jan, 2007.
Link: http://pubs.acs.org/doi/abs/10.1021/es060424e
Abstract
Four different air purification conditions were established in a simulated 3-row 21-seat section of an aircraft cabin: no air purifier; a photocatalytic oxidation unit with an adsorptive prefilter; a second photocatalytic unit with an adsorptive prefilter; and a two-stage sorption-based air filter (gas-phase absorption and adsorption). The air purifiers placed in the cabin air recirculation system were commercial prototypes developed for use in aircraft cabin systems. The four conditions were established in balanced order on 4 successive days of each of 4 successive weeks during simulated 7-h flights with 17 occupants. Proton-transfer reaction mass spectrometry was used to assess organic gas-phase pollutants and the performance of each air purifier. The concentration of most organic pollutants present in aircraft cabin air was efficiently reduced by all three units. The photocatalytic units were found to incompletely oxidize ethanol released by the wet wipes commonly supplied with airline mealsto produce unacceptably high levels of acetaldehyde and formaldehyde.
[Kohl2009] Kohl, I., J. Herbig, J. Beauchamp, J. Dunkl, O. Tietje, and A. Hansel, "Proton-transfer-reaction mass spectrometry online analysis of volatile organic compounds in the exhaled breath: kidney transplant rejection diagnosis", CONFERENCE SERIES, pp. 251, 2009.
Link: http://www.ionicon.com/sites/default/files/uploads/doc/contributions_ptr_ms_Conference_4.pdf#page=251
[Hansel2004] Hansel, A., "Proton transfer mass spectrometer", europhysics news, vol. 35, no. 6, pp. 197–199, 2004.
Link: http://www.europhysicsnews.org/articles/epn/pdf/2004/06/epn04606.pdf
[Wisthaler2005] Wisthaler, A., G. Tamás, D. P. Wyon, P. Strøm-Tejsen, D. Space, J. Beauchamp, A. Hansel, T. D. Maerk, and C. J. Weschler, "Products of ozone-initiated chemistry in a simulated aircraft environment.", Environ Sci Technol, vol. 39, no. 13: International Centre for Indoor Environment and Energy, Technical University of Denmark (DTU), DK-2800 Kgs. Lyngby, Denmark., pp. 4823–4832, Jul, 2005.
Link: http://pubs.acs.org/doi/abs/10.1021/es047992j
Abstract
We used proton-transfer-reaction mass spectrometry (PTR-MS) to examine the products formed when ozone reacted with the materials in a simulated aircraft cabin, including a loaded high-efficiency particulate air (HEPA) filter in the return air system. Four conditions were examined: cabin (baseline), cabin plus ozone, cabin plus soiled T-shirts (surrogates for human occupants), and cabin plus soiled T-shirts plus ozone. The addition of ozone to the cabin without T-shirts, at concentrations typically encountered during commercial air travel, increased the mixing ratio (v:v concentration) of detected pollutants from 35 ppb to 80 ppb. Most of this increase was due to the production of saturated and unsaturated aldehydes and tentatively identified low-molecular-weight carboxylic acids. The addition of soiled T-shirts, with no ozone present, increased the mixing ratio of pollutants in the cabin air only slightly, whereas the combination of soiled T-shirts and ozone increased the mixing ratio of detected pollutants to 110 ppb, with more than 20 ppb originating from squalene oxidation products (acetone, 4-oxopentanal, and 6-methyl-5-hepten-2-one). For the two conditions with ozone present, the more-abundant oxidation products included acetone/propanal (8-20 ppb), formaldehyde (8-10 ppb), nonanal (approximately 6 ppb), 4-oxopentanal (3-7 ppb), acetic acid (approximately 7 ppb), formic acid (approximately 3 ppb), and 6-methyl-5-hepten-2-one (0.5-2.5 ppb), as well as compounds tentatively identified as acrolein (0.6-1 ppb) and crotonaldehyde (0.6-0.8 ppb). The odor thresholds of certain products were exceeded. With an outdoor air exchange of 3 h(-1) and a recirculation rate of 20 h(-1), the measured ozone surface removal rate constant was 6.3 h(-1) when T-shirts were not present, compared to 11.4 h(-1) when T-shirts were present.
[Tholl2006] Tholl, D., W. Boland, A. Hansel, F. Loreto, U. Röse, SR, and JÖRG-PETER. SCHNITZLER, "Practical approaches to plant volatile analysis", The Plant Journal, vol. 45, no. 4: Wiley Online Library, pp. 540–560, 2006.
Link: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-313X.2005.02612.x/full
Abstract
Plants emit volatile organic compounds (VOCs) that play important roles in their interaction with the environment and have a major impact on atmospheric chemistry. The development of static and dynamic techniques for headspace collection of volatiles in combination with gas chromatography–mass spectrometry analysis has significantly improved our understanding of the biosynthesis and ecology of plant VOCs. Advances in automated analysis of VOCs have allowed the monitoring of fast changes in VOC emissions and facilitated in vivo studies of VOC biosynthesis. This review presents an overview of methods for the analysis of plant VOCs, including their advantages and disadvantages, with a focus on the latest technical developments. It provides guidance on how to select appropriate instrumentation and protocols for biochemical, physiological and ecologically relevant applications. These include headspace analyses of plant VOCs emitted by the whole organism, organs or enzymes as well as advanced on-line analysis methods for simultaneous measurements of VOC emissions with other physiological parameters.
O
[Beauchamp2005] Beauchamp, J., A. Wisthaler, A. Hansel, E. Kleist, M. Miebach, ÜLO. NIINEMETS, U. Schurr, and JÜRGEN. WILDT, "Ozone induced emissions of biogenic VOC from tobacco: relationships between ozone uptake and emission of LOX products", Plant, Cell & Environment, vol. 28, no. 10: Wiley Online Library, pp. 1334–1343, 2005.
Link: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3040.2005.01383.x/full
Abstract
Volatile organic compound (VOC) emissions from tobacco (Nicotiana tabacum L. var. Bel W3) plants exposed to ozone (O3) were investigated using proton-transfer-reaction mass-spectrometry (PTR-MS) and gas chromatography mass-spectrometry (GC-MS) to find a quantitative reference for plants’ responses to O3 stress. O3 exposures to illuminated plants induced post-exposure VOC emission bursts. The lag time for the onset of volatile C6 emissions produced within the octadecanoid pathway was found to be inversely proportional to O3 uptake, or more precisely, to the O3 flux density into the plants. In cases of short O3 pulses of identical duration the total amount of these emitted C6 VOC was related to the O3 flux density into the plants, and not to ozone concentrations or dose–response relationships such as AOT 40 values. Approximately one C6 product was emitted per five O3 molecules taken up by the plant. A threshold flux density of O3 inducing emissions of C6 products was found to be (1.6 ± 0.7) × 10−8 mol m−2 s−1.
[Wisthaler2002] Wisthaler, A., A. Hansel, R. R. Dickerson, and P. J. Crutzen, "Organic trace gas measurements by PTR-MS during INDOEX 1999", Journal of geophysical research, vol. 107, no. D19: American Geophysical Union, pp. 8024, 2002.
Link: http://onlinelibrary.wiley.com/doi/10.1029/2001JD000576/abstract
Abstract
A proton-transfer-reaction mass spectrometer (PTR-MS) was used for fast-response measurements of volatile organic compounds (VOCs) onboard the NOAA research vessel Ronald H. Brown during leg 2 (4 March–23 March) of the INDOEX 1999 cruise. In this paper, we present a first overview of the distribution of acetonitrile, methanol, acetone, and acetaldehyde over a broad spatial extent of the Indian Ocean (19°N–13°S, 67°E–75°E). The prevailing atmospheric circulation during the winter monsoon transported polluted air from India and the Middle East over the Indian Ocean to meet pristine southern hemispheric air at the intertropical convergence zone (ITCZ). The chemical composition of air parcels changed according to their geographic origin, which was traced by backtrajectory analysis. The relative abundance of acetonitrile, a selective tracer for biomass burning, to that of carbon monoxide, a general tracer for incomplete combustion, reflected the signature of biomass burning or fossil fuel combustion. This indicated a strong biomass burning impact in W-India, mixed pollution sources in NE-India, and the dominance of fossil fuel combustion in the Middle East. Biomass burning impacted air was rich in methanol (0.70–1.60 ppbv), while acetone (0.80–2.40 ppbv) and acetaldehyde (0.25–0.50 ppbv) were elevated in all continental air masses. Pollution levels decreased toward the ITCZ resulting in minima for methanol, acetone, and acetaldehyde of 0.50, 0.45, and 0.12 ppbv, respectively. The observed abundances suggest that there are unidentified sources of acetone and acetaldehyde in biomass burning impacted air masses and in remote marine air.
[Jordan1997] Jordan, A., A. Hansel, C. WARNECKE, R. Holzinger, P. Prazeller, W. Vogel, and W. Lindinger, ""On-line" Spurengasanalyse im ppt-Bereich und ihre Anwendungen auf Gebieten der Medizin, Lebensmittelforschung und Luftqualität", , no. 84: Ber. nat-.med. Verein Innsbruck, pp. 7-17, 1997.
Link: http://www.landesmuseum.at/pdf_frei_remote/BERI_84_0007-0017.pdf
[Herbig2009a] Herbig, J., M. Müller, S. Schallhart, T. Titzmann, M. Graus, and A. Hansel, "On-line breath analysis with PTR-TOF.", J Breath Res, vol. 3, no. 2: Ionimed Analytik GmbH, Innsbruck, Austria., pp. 027004, Jun, 2009.
Link: http://dx.doi.org/10.1088/1752-7155/3/2/027004
Abstract
We report on on-line breath gas analysis with a new type of analytical instrument, which represents the next generation of proton-transfer-reaction mass spectrometers. This time-of-flight mass spectrometer in combination with the soft proton-transfer-reaction ionization (PTR-TOF) offers numerous advantages for the sensitive detection of volatile organic compounds and overcomes several limitations. First, a time-of-flight instrument allows for a measurement of a complete mass spectrum within a fraction of a second. Second, a high mass resolving power enables the separation of isobaric molecules and the identification of their chemical composition. We present the first on-line breath measurements with a PTR-TOF and demonstrate the advantages for on-line breath analysis. In combination with buffered end-tidal (BET) sampling, we obtain a complete mass spectrum up to 320 Th within one exhalation with a signal-to-noise ratio sufficient to measure down to pptv levels. We exploit the high mass resolving power to identify the main components in the breath composition of several healthy volunteers.
[Kohl2011] Kohl, I., J. Herbig, J. Beauchamp, J. Dunkl, O. Tietje, and A. Hansel, "Online breath analysis of volatile organic compounds with PTR-MS: a guanidino breath marker for the status of uremia and kidney transplant rejection diagnosis.", 4th International PTR-MS Conference on Proton Transfer Reaction Mass Spectrometry and Its Applications, pp. 251, 2011.
Link: http://www.ionicon.com/sites/default/files/uploads/doc/contributions_ptr_ms_Conference_5.pdf
[Fares2013] Fares, S., R. Schnitzhofer, X. Jiang, A. Guenther, A. Hansel, and F. Loreto, "Observations of diurnal to weekly variations of monoterpene-dominated fluxes of volatile organic compounds from Mediterranean forests: implications for regional modeling.", Environ Sci Technol, Sep, 2013.
Link: http://dx.doi.org/10.1021/es4022156
Abstract
The Estate of Castelporziano (Rome, Italy) hosts many ecosystems representative of Mediterranean vegetation, especially holm oak and pine forests, and dune vegetation. In this work, Basal Emission Factors (BEFs) of biogenic volatile organic compounds (BVOCs) obtained by Eddy Covariance in a field campaign using a Proton Transfer Reaction - Time of Flight - Mass Spectrometer (PTR-TOF-MS) were compared to BEFs reported in previous studies that could not measure fluxes in real-time. Globally, broadleaf forests are dominated by isoprene emissions, but these Mediterranean ecosystems are dominated by strong monoterpene emitters, as shown by the new BEFs. The original and new BEFs were used to parameterize the Model of Emissions of Gases and Aerosols from Nature (MEGAN v2.1), and model outputs were compared with measured fluxes. Results showed good agreement between modelled and measured fluxes when a model was used to predict radiative transfer and energy balance across the canopy. We then evaluated whether changes in BVOC emissions can affect the chemistry of the atmosphere and climate at a regional level. MEGAN was run together with the land surface model (Community Land Model, CLM v4.0) of the Community Earth System Model (CESM v1.0). Results highlighted that tropospheric ozone concentration and air temperature predicted from the model are sensitive to the magnitude of BVOC emissions, thus demonstrating the importance of adopting the proper BEF values for model parameterization.
[Norman2007] Norman, M., A. Hansel, and A. Wisthaler, "O2+ as reagent ion in the PTR-MS instrument: Detection of gas-phase ammonia", International Journal of Mass Spectrometry, vol. 265, no. 2: Elsevier, pp. 382–387, 2007.
Link: http://www.sciencedirect.com/science/article/pii/S1387380607002515
Abstract
Oxygen was used as a source gas in a conventional Innsbruck PTR-MS instrument to produce O2+ ions as chemical ionization (CI) reagents instead of H3O+ ions. The use of O2+ ions as CI reagents allows for fast, highly sensitive and specific measurements of gas-phase ammonia (NH3) via the electron transfer reaction O2+ + NH3 → NH3+ + O2. The instrument was tested to be linear in the 2–2000 ppbv range. Instrument sensitivity was observed to be humidity-independent and amounted to ∼40 cps/ppbv. The instrumental background was determined by sampling NH3-free air from a heated platinum/palladium catalyst. A humidity-dependent increase of the instrumental background from 70 pptv at dry conditions to 470 pptv at humid conditions was observed. The corresponding 2σ-detection limits at 1 s signal integration time were 90 pptv for dry conditions and 230 pptv for humid conditions, respectively. The observed background may be intrinsically formed in the instrument's ion source but it may also be the result of incomplete NH3 oxidation in the catalyst used for zeroing. The reported background levels and detection limits are thus to be considered as upper limits. The 1/e response time of the instrument was in the range of 3–5 s. The PTR-MS instrument was successfully deployed in the field to monitor changes in gas-phase NH3 concentrations in the few seconds to tens of seconds time range. Laboratory intercomparison measurements between the PTR-MS instrument and a commercial NH3 analyzer (AiRRmonia) were in good agreement. The use of O2+ ions as CI reagents will significantly improve the analytical capabilities of the Innsbruck PTR-MS instrument.
M
[Fischer2013] Fischer, L., V. Ruzsanyi, K. Winkler, R. Gutmann, A. Hansel, and J. Herbig, "Micro-Capillary-Column PTR-TOF", 6th International PTR-MS Conference on Proton Transfer Reaction Mass Spectrometry and Its Applications, pp. 162, 2013.
Link: http://www.ionicon.com/sites/default/files/uploads/doc/contributions_ptr_ms_Conference_6.pdf
[Mayrhofer2006] Mayrhofer, S., T. Mikoviny, S. Waldhuber, A. O. Wagner, G. Innerebner, I. H. Franke-Whittle, T. D. Maerk, A. Hansel, and H. Insam, "Microbial community related to volatile organic compound (VOC) emission in household biowaste.", Environ Microbiol, vol. 8, no. 11: Institut fuer Mikrobiologie, Universitaet Innsbruck, Innsbruck, Austria. sabine.mayrhofer@uibk.ac.at, pp. 1960–1974, Nov, 2006.
Link: http://dx.doi.org/10.1111/j.1462-2920.2006.01076.x
Abstract
Malodorous emissions and potentially pathogenic microorganisms which develop during domestic organic waste collection are not only a nuisance but may also pose health risks. The aim of the present study was to determine whether the presence of specific microorganisms in biowastes is directly related to the composition of the emitted volatile organic compounds (VOCs). The succession of microbial communities during 16 days of storage in organic waste collection bins was studied by denaturing gradient gel electrophoresis (DGGE) of amplified 16S ribosomal DNA in parallel with a classical cultivation and isolation approach. Approximately 60 different bacterial species and 20 different fungal species were isolated. Additionally, some bacterial species were identified through sequencing of excised DGGE bands. Proton transfer reaction mass spectrometry (PTR-MS) was used to detect VOCs over the sampling periods, and co-inertia analyses of VOC concentrations with DGGE band intensities were conducted. Positive correlations, indicating production of the respective VOC or enhancement of microbial growth, and negative correlations, indicating the use of, or microbial inhibition by the respective compound, were found for the different VOCs. Measurement of the VOC emission pattern from a pure culture of Lactococcus lactis confirmed the positive correlations for the protonated masses 89 (tentatively identified as butyric acid), 63 (tentatively identified as dimethylsulfide), 69 (likely isoprene) and 73 (likely butanone).
[Hansel2000] Hansel, A., and A. Wisthaler, "A method for real-time detection of PAN, PPN and MPAN in ambient air", Geophysical research letters, vol. 27, no. 6: Wiley Online Library, pp. 895–898, 2000.
Link: http://onlinelibrary.wiley.com/doi/10.1029/1999GL010989/full

Pages

Featured Articles

Download Contributions to the International Conference on Proton Transfer Reaction Mass Spectrometry and Its Applications:

 

Selected PTR-MS related Reviews

F. Biasioli, C. Yeretzian, F. Gasperi, T. D. Märk: PTR-MS monitoring of VOCs and BVOCs in food science and technology, Trends in Analytical Chemistry 30 (7) (2011).
Link

J. de Gouw, C. Warneke, T. Karl, G. Eerdekens, C. van der Veen, R. Fall: Measurement of Volatile Organic Compounds in the Earth's Atmosphere using Proton-Transfer-Reaction Mass Spectrometry. Mass Spectrometry Reviews, 26 (2007), 223-257.
Link

W. Lindinger, A. Hansel, A. Jordan: Proton-transfer-reaction mass spectrometry (PTR–MS): on-line monitoring of volatile organic compounds at pptv levels, Chem. Soc. Rev. 27 (1998), 347-375.
Link

 

Lists with PTR-MS relevant publications of the University of Innsbruck can be found here: Atmospheric and indoor air chemistry, IMR, Environmental Physics and Nano-Bio-Physics

 

Download the latest version of the IONICON publication database as BibTeX.