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Abstract

A method of 11C-methionine synthesis using ‘bubbling’ method is presented. 11C-methionine was synthesized via 11C methylation from L-cysteine thiolactone (2 mg) in a 300 μL solution of 2:1:1 (v/v) 1 M NaOH, ethanol, and water at ambient temperature (85°C, 5 min). The radiochemical purity of radiotracer was higher than 99% and enantiomeric purity (L-11C-methionine) was 91.6 ± 0.4%. The final product met the requirements of European Pharmacopoeia monograph. The proposed 11C-methionine synthesis is a reliable tool for routine manufacturing in clinical applications and animal studies.

hyperbaric facilities ventilation. Wydawnictwo Polskiego Towarzystwa Medycyny i Techniki Hiperbarycznej, Gdynia, ISBN 978-83-924989-0-2. 24. DCIEM (1986): Procedures for Doppler ultrasonic monitoring of divers for intravascular bubbles. Defense and Civil Institute of Environmental Medicine, Toronto, No. 86-C-25. 25. Kłos R. (2012): Intravascular free gas phase detection. Zeszyty Naukowe Akademii Marynarki, Vol. 188, 85–96, ISSN 0860-889X.

References 1. Collins, P. F., N. M. Sarji, W. W. Lawrence, and J. F. Williams: An automated method for the determination of total aldehydes in gas phase of cigarette smoke; Tobacco Science 14 (1970) 182-186. 2. Collins, P. F., N. M. Sarji, and J. F. Williams: An automated method for determination of hydrogen cyanide in cigarette smoke; Tobacco Science 14 (1970) 12-15. 3. Keith, C. H., and J. R. Newsome: Quantitative studies on cigarette smoke, I: An automated smoking machine; Tobacco Science 1 (1957) 51-57.

, Lyon, 1976, pp. 215-225. 4. Barkemeyer, H., and F. Seehofer: Zur Untersuchung der Gas-Dampf-Phase des Cigarettenrauches, 2. Mitteilung: Zur Bestimmung des Stickstoffmonoxids (NO) aus der Gasphase des Cigarettenrauches; Beitr. Tabakforsch. 4 {1968) 278-282. 5. Vilcins, G., and J. O. Lephardt: Ageing processes of cigarette smoke I Formation of methyl nitrite; Chem. Incl.. (Lond.) 1975,974-975. 6. Baulch, D. L., D. D. Drysdale, D. G. Horne and A. C. Uoyd: Evaluated kinetic data for high-temperature reactions, Vol. 1: Homogeneous gas-phase reactions of the H 2 -O 2

References 1. Osbome, J. S., S. Adamek and M. E. Hobbs: Anal. Chem. 28 (1.956) 211.. 2. Philippe, R. J., and M. E. Hobbs: Anal. Chem. 28 (1.956) 2002. 3. Patton, H. W., and G. P. Touey: Anal. Chem. 28 (1.956) 1685. 4. Philippe, R. J., H. Moore, R. G. Honeycutt and J. M. Ruth: Anal. Chem. 36 (1964) 859. 5. Newsome, J. R., V. Norman and C. H. Keith: Tobacco Science 9 (1965) 102. 6. Parrish, M. E.: Personal communication of gas chromatographic work done at Philip Morris Research Center, 1973. 7. Vikins, G.: Infrared analysis of ethylene and isoprene in the gas

References 1. Gustafsson, L.: Determination of ultra micro amounts of sulphate as methylene blue, I. The colour reaction; Talanta 4 (1960) 227-235. 2. Horton, A. D., and M. R. Guerin: Quantitative determination of sulfur compounds in the gas phase of cigarette smoke; J. Chromatography 90 (1974) 63-70. 3. Johnson, C. M., and H. Nishita: Microestimation of sulfur in plant materials, soils, and irrigation waters; Anal. Chem. 24 (1952) 736-742. 4. Mattina, C. F., Jr.: A potentiometric method for the determination of hydrogen cyanide and hydrogen sulfide in cigarette

579 (2014) 93-99. 24. Li, B., H. R. Pang, L. C. Zhao, B. Wang, C. Liu, K. G. McAdam, and D. S. Luo: Quantifying Gas-Phase Tem-perature Inside a Burning Cigarette; Ind. Eng. Chem. Res. 53 (2014) 7810-7820. 25. Rosin, P. and E. Rammler: The Laws Governing the Fineness of Powdered Coal; J. Inst. Fuel. 7 (1933) 29-36. 26. International Organization for Standardization (ISO): International Standard ISO 3308:2000. Routine Analyti-cal Cigarette-Smoking Machine – Definition and Standard Conditions; 4th Edition, ISO, Geneva, Swit-zerland, 2000. 27. Baker, R. R. and M. Dixon

Abstract

By the use of gaschromatographic and mass spectrometric methods gas phase condensate from cigarette smoke, isolated on a preparative scale, has been compared with the native gas phase from the smoke of the same cigarettes and investigated for qualitative composition. With regard to composition, there is a satisfactory conformity between both mixtures of substances. It has been possible to identify or to characterize more than 60 constituents

The aim of this study was to examine the impact of three main tobacco types (flue-cured FC, air-cured AC and sun-cured SC) and two tobacco-based materials (reconstituted tobacco - recon RT and expanded stem) on the formation of carbon monoxide (CO) in the gas phase of mainstream cigarette smoke. The results showed that the type of tobacco examined had a significant impact on the amount of carbon monoxide production in the gas phase of cigarette smoke. AC and SC tobaccos had the most evident impact. The amount of tobacco in mixtures M1, M2 and M3 as well as the addition of expanded stems had an impact on the amount of CO formed in the cigarette smoke. There is weak correlation between CO content in the smoke and the chemical composition of the tobacco. Draw resistance had an impact on CO production. The research results are of great importance, since tobacco selection is the first step in the production of cigarettes with reduced emission of harmful elements contained in the smoke.

Abstract

Formation profiles have been obtained for methane, ethane, ethene, propane, propene, butanes, butenes, isoprene, formaldehyde, acetaldehyde, acetone, 2-butanone, benzene, and toluene from the thermal decomposition of tobacco in the presence of helium and air. These data show that in helium the temperatures for optimum formation of gas phase constituents were: hydrocarbons, 450°C; aldehydes, 300°C; ketones, 450°C; isoprene, 380° and 475°C; and aromatic hydrocarbons, 450°C. Air enhances the formation of these gas phase constituents at 280°C and in most cases at 420°C, the latter temperature is an area of major weight loss of tobacco. Each formation maximum corresponds to a rate of weight loss maximum exhibited by derivative thermogravimetry. The results also show that it is possible to use effluent gas analysis to define the thermal behaviour of tobacco in terms of the formation of the gas phase constituents which provide a means to elicit the processes that occur during the thermal decomposition of tobacco.