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Scientific Articles - PTR-MS Bibliography

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Found 63 results
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2005
[Spirig2005] Spirig, C., A. Neftel, C. Ammann, J. Dommen, W. Grabmer, A. Thielmann, A. Schaub, J. Beauchamp, A. Wisthaler, A. Hansel, et al., "Eddy covariance flux measurements of biogenic VOCs during ECHO 2003 using proton transfer reaction mass spectrometry", Atmospheric Chemistry and Physics, vol. 5, no. 2, pp. 465–481, 2005.
Link: http://hal.archives-ouvertes.fr/hal-00295614/
Abstract
Within the framework of the AFO 2000 project ECHO, two PTR-MS instruments were operated in combination with sonic anemometers to determine biogenic VOC fluxes from a mixed deciduous forest site in North-Western Germany. The measurement site was characterised by a forest of inhomogeneous composition, complex canopy structure, limited extension in certain wind directions and frequent calm wind conditions during night time. The eddy covariance (EC) technique was applied since it represents the most direct flux measurement approach on the canopy scale and is, therefore, least susceptible to these non-ideal conditions. A specific flux calculation method was used to account for the sequential multi-component PTR-MS measurements and allowing an individual delay time adjustment as well as a rigorous quality control based on cospectral analysis. The validated flux results are consistent with light and temperature dependent emissions of isoprene and monoterpenes from this forest, with average daytime emissions of 0.94 and 0.3µg m-2s-1, respectively. Emissions of methanol reached on average 0.087µg m-2s-1 during daytime, but fluxes were too small to be detected during night time. Upward fluxes of the isoprene oxidation products methyl vinyl ketone (MVK) and methacrolein (MACR) were also found, being two orders of magnitude lower than those of isoprene. Calculations with an analytical footprint model indicate that the observed isoprene fluxes correlate with the fraction of oaks within the footprints of the flux measurement.
2004
[Jaksch2004] Jaksch, D., R. Margesin, T. Mikoviny, JD. Skalny, E. Hartungen, F. Schinner, NJ. Mason, and TD. Märk, "The effect of ozone treatment on the microbial contamination of pork meat measured by detecting the emissions using PTR-MS and by enumeration of microorganisms", International Journal of Mass Spectrometry, vol. 239, no. 2: Elsevier, pp. 209–214, 2004.
Link: http://www.sciencedirect.com/science/article/pii/S1387380604003471
Abstract
In this paper, we report the results of treating commercial samples of pork meat with ozone in order to determine whether such treatment reduces microbial growth and hence extends the shelf lifetime of such products. The technique of Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) was used to study volatile emissions with the signal detected at mass 63 (assumed to be a measure for dimethylsulphide) being used as a diagnostic of bacterial activity. Such a signal was found to strongly increase with time for an untreated meat sample whereas ozone-treated meat samples showed much reduced emissions—suggesting that the microbial activity had been greatly suppressed by ozone treatment. An independent analysis, however, revealed that microbial counts were very high, independent of the treatment.
[Tani2004] Tani, A., S. Hayward, A. Hansel, and N. C Hewitt, "Effect of water vapour pressure on monoterpene measurements using proton transfer reaction-mass spectrometry (PTR-MS)", International Journal of Mass Spectrometry, vol. 239, no. 2: Elsevier, pp. 161–169, 2004.
Link: http://www.sciencedirect.com/science/article/pii/S1387380604003495
Abstract
The effects of water vapour pressure (WVP) on the fragmentation of seven monoterpene and related C10 volatile organic compounds (VOCs) in the drift tube of a proton transfer reaction-mass spectrometer (PTR-MS) were investigated. In addition, the combined effects of varying WVP and the ratios of electric field strength to number density of the buffer gas (E/N) were investigated in detail for three of these compounds, the monoterpenes α-pinene and sabinene plus the related C10 VOC p-cymene. Under normal operating conditions (E/N = 124 Td), WVP affected the fragment patterns of all compounds with the exception of β-pinene and the three oxygenated C10 VOCs. WVP had a significant effect on the fragment patterns of α-pinene and sabinene at the lower E/N ratios (around 80 Td) but had little effect on fragmentation towards the higher E/N ratios used here (∼142 Td). On the other hand, p-cymene fragmentation was most affected by WVP under normal operating conditions. PTR-MS sensitivity towards the three compounds was also considered under three conditions where reaction was assumed with (1) H3O+ only; (2) H3O+ and H3O+H2O; and (3) H3O+, H3O+H2O and H3O+(H2O)2. Our results indicate that α-pinene and sabinene react not only with H3O+ and H3O+H2O via direct proton transfer but also with H3O+(H2O)2 via ligand switching. p-Cymene seems to react only with H3O+ via direct proton transfer and with H3O+H2O via ligand switching. It is speculated that the WVP effect on fragmentation results from the differing abundances of hydrated reagent ions which causes different frequencies of individual reactions to occur, thus, determining how ‘soft’ the overall reaction is. These results also indicate that under normal conditions, a correction should be made for WVP if the concentration of p-cymene in air samples is to be determined from the single ion signal of either protonated molecular ions or the most dominant fragment ions.
[Northway2004] Northway, MJ., JA. De Gouw, DW. Fahey, RS. Gao, C. Warneke, JM. Roberts, and F. Flocke, "Evaluation of the role of heterogeneous oxidation of alkenes in the detection of atmospheric acetaldehyde", Atmospheric Environment, vol. 38, no. 35: Elsevier, pp. 6017–6028, 2004.
Link: http://www.sciencedirect.com/science/article/pii/S1352231004006429
Abstract
Unexpectedly high values for acetaldehyde have been observed in airborne measurements using a proton-transfer-reaction mass spectrometry instrument. The acetaldehyde values increase with increasing ambient ozone levels with a ratio up to 5 pptv acetaldehyde per ppbv of ozone in the free troposphere. The elevated values of acetaldehyde cannot easily be explained from known tropospheric chemistry. Here, we investigate the possibility that the elevated acetaldehyde signals are due to a sampling artifact. Laboratory experiments show that the elevated signals are not due to changes of the ion chemistry in the instrument, or from the instrument materials reacting with ozone. The heterogeneous oxidation of a number of unsaturated organic compounds is investigated as a possible source for a chemical artifact produced in the instrument inlet. The products of the heterogeneous reactions are consistent with gas phase chemistry, and the ozonolysis of some alkenes does produce acetaldehyde when they have the appropriate hydrocarbon structure. The amount of reactive material in the free troposphere expected to accumulate in the aircraft inlet is unknown, and the exact origin of reactive compounds that contribute to the artifact production remains unresolved.
[Karl2004] Karl, T., M. Potosnak, A. Guenther, D. Clark, J. Walker, J. D. Herrick, and C. Geron, "Exchange processes of volatile organic compounds above a tropical rain forest: Implications for modeling tropospheric chemistry above dense vegetation", Journal of geophysical research, vol. 109, no. D18: American Geophysical Union, pp. D18306, 2004.
Link: http://www.agu.org/pubs/crossref/2004/2004JD004738.shtml
Abstract
Disjunct eddy covariance in conjunction with continuous in-canopy gradient measurements allowed for the first time to quantify the fine-scale source and sink distribution of some of the most abundant biogenic (isoprene, monoterpenes, methanol, acetaldehyde, and acetone) and photooxidized (MVK+MAC, acetone, acetaldehyde, acetic, and formic acid) VOCs in an old growth tropical rain forest. Our measurements revealed substantial isoprene emissions (up to 2.50 mg m−2 h−1) and light-dependent monoterpene emissions (up to 0.33 mg m−2 h−1) at the peak of the dry season (April and May 2003). Oxygenated species such as methanol, acetone, and acetaldehyde were typically emitted during daytime with net fluxes up to 0.50, 0.36, and 0.20 mg m−2 h−1, respectively. When generalized for tropical rain forests, these fluxes would add up to a total emission of 36, 16, 19, 106, and 7.2 Tg/yr for methanol, acetaldehyde, acetone, isoprene, and monoterpenes, respectively. During nighttime we observed strong sinks for oxygenated and nitrogen-containing compounds such as methanol, acetone, acetaldehyde, MVK+MAC, and acetonitrile with deposition velocities close to the aerodynamic limit. This suggests that the canopy resistance (Rc) is very small and not the rate-limiting step for the nighttime deposition of many VOCs. Our measured mean dry deposition velocities of methanol, acetone, acetaldehyde, MVK+MAC, and acetonitrile were a factor 10–20 higher than estimated from traditional deposition models. If our measurements are generalized, this could have important implications for the redistribution of VOCs in atmospheric chemistry models. Our observations indicate that the current understanding of reactive carbon exchange can only be seen as a first-order approximation.
2003
[Lirk2003] Lirk, P., F. Bodrogi, H. Raifer, K. Greiner, H. Ulmer, and J. Rieder, "Elective haemodialysis increases exhaled isoprene.", Nephrol Dial Transplant, vol. 18, no. 5: Department of Anesthesiology and Critical Care Medicine, Leopold Franzens University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria., pp. 937–941, May, 2003.
Link: http://ndt.oxfordjournals.org/content/18/5/937.short
Abstract
Uraemic odour is a characteristic feature of patients with end-stage renal disease (ESRD). However, few investigations have been carried out into the composition of exhaled air in ESRD patients undergoing haemodialysis (HD). Increases of exhaled isoprene levels by a factor of up to 2.7 following HD have been reported.We attempted to confirm these findings in 50 patients undergoing HD using haemophan (n=23) or polysulphone (n=27) dialysis membranes. Parallel evaluation of ambient air, calorie intake, medication and haemodynamic variables was performed. Samples were analysed using proton transfer reaction-mass spectrometry (PTR-MS).Significant changes in breath isoprene concentration were observed when comparing patients before [39.14+/-14.96 parts per billion (ppbv)] and after (63.54+/-27.59 ppbv) dialysis (P<0.001). The quotient of values before and after dialysis was 1.84 (SD 1.41). No significant differences in isoprene kinetics were found between the use of haemophan and polysulphone membranes. No significant correlations were observed between isoprene quotients and variations in blood pressure during HD, calorie intake, ingestion of lipid-lowering drugs or serum lipid levels.Isoprene concentration was higher in the exhaled air of patients after HD as compared with values before HD. Large interindividual variability existed in isoprene kinetics. Oxidative stress appears to be an unlikely cause for this rise. An alternative hypothesis is an influence of respiratory variables on isoprene exhalation based upon Henry's law constant. We therefore propose to perform online monitoring of isoprene exhalation by PTR-MS during the HD session to investigate the possible influence of respiratory variables.
[DeGouw2003] De Gouw, JA., C. Warneke, DD. Parrish, JS. Holloway, M. Trainer, and FC. Fehsenfeld, "Emission sources and ocean uptake of acetonitrile (CH3CN) in the atmosphere", Journal of geophysical research, vol. 108, no. D11: American Geophysical Union, pp. 4329, 2003.
Link: http://www.agu.org/pubs/crossref/2003/2002JD002897.shtml
Abstract
Airborne measurements of acetonitrile (CH3CN) were made off the U.S. west coast, over California, and during two transfer flights over the U.S. in April and May of 2002. Acetonitrile was strongly enhanced in the plumes from two forest fires, confirming the usefulness of the measurement as an indicator for biomass burning emissions. The emission ratios relative to CO of acetonitrile in the two plumes were slightly higher than previously reported values for fires burning in other fuel types. No significant acetonitrile release was observed in the Los Angeles basin or from other point sources (ships and a power plant). Acetonitrile concentrations were significantly reduced in the marine boundary layer indicating the presence of an ocean uptake sink. Increased loss of acetonitrile was observed close to the coast, suggesting that acetonitrile was efficiently lost by dissolving in the upwelling ocean water, or by biological processes in the surface water.
2001
[Karl2001a] Karl, T., A. Guenther, A. Jordan, R. Fall, and W. Lindinger, "Eddy covariance measurement of biogenic oxygenated VOC emissions from hay harvesting", Atmospheric Environment, vol. 35, no. 3: Elsevier, pp. 491–495, 2001.
Link: http://www.sciencedirect.com/science/article/pii/S1352231000004052
Abstract
Biogenic oxygenated volatile organic compound (VOC) fluxes have been directly measured by eddy covariance using the combination of a fast response, real-time \{VOC\} sensor and an acoustic anemometer. \{VOC\} detection is based on proton-transfer reaction mass spectrometry which has currently a response time of ca. 0.8&#xa0;s and the system is suitable for making nearly unattended, long-term and continuous measurements of \{VOC\} fluxes. The eddy covariance system has a detection limit, for most VOCs, of less than 0.1&#xa0;mg&#xa0;m−2&#xa0;h−1. The system was field tested above a hayfield near St. Johann, Austria where cut and drying grasses released a variety of VOCs. High fluxes were observed for about 2 days after cutting and were dominated by methanol (1–8.4&#xa0;mg&#xa0;m−2&#xa0;h−1), acetaldehyde (0.5–3&#xa0;mg&#xa0;m−2&#xa0;h−1), hexenals (0.1–1.5&#xa0;mg&#xa0;m−2&#xa0;h−1) and acetone (0.1–1.5&#xa0;mg&#xa0;m−2&#xa0;h−1). The eddy covariance measurements generally agreed with flux estimates based on enclosure measurements and surface layer gradients. The sensitivity and selectivity of the system make it suitable for quantifying the fluxes of the dominant biogenic \{VOCs\} from a variety of landscapes and sources.
[Lindinger2001] Lindinger, W., R. Fall, and T. Karl, "Environmental, food and medical applications of proton-transfer-reaction mass spectrometry (PTR-MS)", , vol. 4: Elsevier: Amsterdam, The Netherlands, pp. 1-48, 2001.
Link: http://acd.ucar.edu/ tomkarl/ptrmschap.pdf
Abstract
The development of proton-transfer-reaction mass spectrometry (PTR-MS) as a tool for the analysis of volatile organic compounds (VOCs) is described. PTR-MS is based on the rapid, non-dissociative transfer of protons from H3Oþ to most common VOCs, but not to the principal gases in the air sample. Recent developments in the design of PTR-MS instruments allow detection of some VOCs in the parts per trillion by volume range. This sensitivity and the capability of PTR-MS instruments to be operated for extended periods in both laboratory and field settings has allowed exploration of many aspects of VOC analysis in environmental, food and medical applications.
2000
[Holzinger2000] Holzinger, R., L. Sandoval-Soto, S. Rottenberger, PJ. Crutzen, J. Kesselmeier, and , "Emissions of volatile organic compounds from Quercus ilex L. measured by proton transfer reaction mass spectrometry under different environmental conditions", Journal of Geophysical Research, vol. 105, no. D16, pp. 20573–20579, 2000.
Link: http://www.agu.org/journals/jd/jd0016/2000JD900296/pdf/2000JD900296.pdf
1999
[Gouw1999] De Gouw, J. A., C. J. Howard, T. G. Custer, and R. Fall, "Emissions of volatile organic compounds from cut grass and clover are enhanced during the drying process", Geophysical Research Letters, vol. 26, no. 7: American Geophysical Union, pp. 811–814, 1999.
Link: http://onlinelibrary.wiley.com/doi/10.1029/1999GL900076/full
1997
[Lindinger1997] Lindinger, W., J. Taucher, A. Jordan, A. Hansel, and W. Vogel, "Endogenous production of methanol after the consumption of fruit", Alcoholism: Clinical and Experimental Research, vol. 21, no. 5: Wiley Online Library, pp. 939–943, 1997.
Link: http://onlinelibrary.wiley.com/doi/10.1111/j.1530-0277.1997.tb03862.x/abstract
Abstract
After the consumption of fruit, the concentration of methanol in the human body increases by as much as an order of magnitude. This is due to the degradation of natural pectin (which is esterified with methyl alcohol) in the human colon. In vivo tests performed by means of proton-transfer-reaction mass spectrometry show that consumed pectin in either a pure form (10 to 15 g) or a natural form (in 1 kg of apples) induces a significant increase of methanol in the breath (and by inference in the blood) of humans. The amount generated from pectin (0.4 to 1.4 g) is approximately equivalent to the total daily endogenous production (measured to be 0.3 to 0.6 g/day) or that obtained from 0.3 liters of 80-proof brandy (calculated to be 0.5 g). This dietary pectin may contribute to the development of nonalcoholic cirrhosis of the liver.
[Hansel1997] Hansel, A., W. Singer, A. Wisthaler, M. Schwarzmann, and W. Lindinger, "Energy dependencies of the proton transfer reactions H3O++ CH2O CH2OH++ H2O", International journal of mass spectrometry and ion processes, vol. 167: Elsevier, pp. 697–703, 1997.
Link: http://www.sciencedirect.com/science/article/pii/S0168117697001286
Abstract
The proton transfer reaction system View the MathML source has been investigated in both directions as a function of the mean relative kinetic energy, KEcm, between the reactants from 0.05 eV to 1 eV in a selected ion flow drift tube (SIFDT) experiment. The rate constant kf for the forward channel follows closely the calculated collisional limiting value, kc, showing a slightly negative energy dependence. The rate constant, kr, for the reverse channel, which is endoergic by 5.2 kcal mol−1, increases from kr = 2.3 × 10−12 cm3 s−1 at KEcm = 0.05 eV to kr = 2 × 10−10 cm3 s−1 at KEcm = 1 eV. This endoergic reaction is paralleled by an associative channel forming CH2OH+·H2O, which undergoes ligand switching with water molecules to produce H3O+·H2O, yielding a bond energy BE(CH2OH+−H2O) = 27.7 kcal mol−1 in agreement with previous data. The present results are important requisites to monitor the formaldehyde concentrations in air using proton transfer reactionmass spectrometry (PTR-MS).

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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).
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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.
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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

 

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