Gas chromatography headspace

The headspace chamber is heated to take advantage of the increase of vapour pressure with temperature. An aliquot of the vapour phase (headspace) is then injected into the column to proceed as regular GC. In this way, HS-GC is used to analyse low concentrations of components with a high vapour pressure in a low vapour pressure matrix. 

Important factors influencing the analyte volatilisation process are related to diffusion, porosity, and surface area (for solids). To obtain reproducible results it is necessary to control storage temperature and time strictly. The temperature of the sample is very important because of the specific boiling points of the various analytes. The partition coefficient, K, at equilibrium, is 

Parameters influencing the performance of headspace methods include sample preparation, sample temperature, equilibration time, carrier gas pressure, pressurisa-tion time, sampling time and transfer line temperature. For validation of headspace instrumentation, see Kolb and Ettre [207], 

With regard to the solution approach, it is imperative that the solvent used be of the highest possible purity. Solution headspace is applicable to a much wider range of samples than the solid approach. When working with 

Advantages and disadvantages of HS-GC over regular GC are summarised in Table. 4.26. HS-GC fingerprinting chromatograms obviously include only the volatile components present and do not provide a complete picture of sample composition on the other hand, when solvent extraction is used, all the soluble sample constituents are removed, including also those having no appreciable vapour pressure at the equilibration temperature. Headspace analysis enhances the peaks of volatile trace components. 

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Blood and urine are most often analyzed for alcohol by headspace gas chromatography (qv) using an internal standard, eg, 1-propanol. Assays are straightforward and lend themselves to automation (see Automated instrumentation). Urine samples are collected as a voided specimen, ie, subjects must void their bladders, wait about 20 minutes, and then provide the urine sample. Voided urine samples provide the most accurate deterrnination of blood alcohol concentrations. Voided urine alcohol concentrations are divided by a factor of 1.3 to determine the equivalent blood alcohol concentration. The 1.3 value is used because urine has approximately one-third more water in it than blood and, at equiUbrium, there is about one-third more alcohol in the urine as in the blood. 

Principle. The content of 1,4-dioxane in ether sulfates is determined by headspace gas chromatography according to the standard additions method. The method is suitable for all ether sulfates and gives reliable results independent of chain length distribution and water content. 

Dietz EA Jr, Singley KF. 1979. Determination of chlorinated hydrocarbons in water by headspace gas chromatography. Anal Chem 51 1809-1814. 

Entz RC, Thomas KW, Diachenko GW. 1982. Residues of volatile halocarbons in foods using headspace gas chromatography. J Agric Food Chem 30 846-849. 

Ramsey JD, Flanagan RJ. 1982. Detection and identification of volatile organic compounds in blood by headspace gas chromatography as an aide to the diagnosis of solvent abuse. J Chromatogr 240 423-444. 

Miettinen, S.M. et al.. Effect of emulsion characteristics on the release of aroma as detected by sensory evaluation, static headspace gas chromatography, and electronic nose, J. Agric. Food Chem., 50, 4232, 2002. 

B. Kolb, "Applied Headspace Gas Chromatography", Heyden, London, UK, 1980. 

B. Kolb and L.S. Ettre, Static Headspace-Gas Chromatography. Theory and Practice, Wiley-VCH, New York, NY (1997). 

H. Hachenberg and K. Beringer, Die Headspace-Gas-chromatographie als Analysen- und Messmethode, Springer-Verlag, Berlin (1996). 

Part 22 Determination of ethylene oxide and propylene oxide in plastics Headspace gas chromatography with diethyl ether as internal standard... 

Page BD. 1985. Determination of acrylonitrile in foods by headspace-gas chromatography with nitrogen-sensitive detection Collaborative study. J Assoc Off Anal Chem 68 776-782. 

Hussam, A., Carr, P. W. (1985) A study of a rapid and precise methodology for the measurement of vapor-liquid equilibria by headspace gas chromatography. Anal. Chem. 57, 793-801. 

Bakierowska, A.-M., Trzeszqzynski, J. (2003) Graphical method for the determination of water/gas partition coefficients of volatile organic compounds by a headspace gas chromatography technique. Fluid Phase Equil. 213, 139-146. 

Kolb, B., Welter, C., Bichler, C. (1992) Determination of partition coefficients by automatic equilibrium headspace gas chromatography by vapor phase calibration. Chromatographia 34, 235-240. 

Schoene, S., Steinhanses, J. (1985) Determination of Henry s law constant by automated headspace gas chromatography determination of dissolved gases. Fresenius Z. Anal. Chem. 321, 538-543. 

Lansens, P., M. Leermakers, and W. Baeyens. 1991. Determination of methylmercury in hsh by headspace-gas chromatography with microwave-induced-plasma detection. Water Air Soil Pollut. 56 103-115. 

Seto Y. 1994. Determination of volatile substances in biological samples by headspace gas chromatography. J Chromatogr A 674 25-62. 

Krock and Wilkins [4] have used multidimensional gas chromatography with infrared and mass spectrometric detection to determine organics in soil. Direct acetylation followed by gas chromatography with flame ionization, electron capture and mass spectrometric detectors has been used to determine phenolic residues in soil [5]. Llopart-Visoso et al. [6] have used direct acetylation followed by headspace gas chromatography to determine phenolic and cresolic components of soil. 

Cardeal ZL, Pradeau D, Hamon M. 1993. Determination of HCN by headspace gas chromatography using an improved method of standardization. Chromatographia 37(11-12) 613-617. 

Odoul M, Fouillet B, Nouri B, et al. 1994. Specific determination of cyanide in blood by headspace gas chromatography. J Anal Toxicol 18(4) 205-207. 

Seto Y, Tsunoda N, Ohta H, et al. 1993. Determination of blood cyanide by headspace gas chromatography with nitrogen phosphorus detection and using a megabore capillary column. Analytica ChimicaActa 276 247-259. 

Adlard ER, Milne CB, Tindle PE. 1981. The determination of phenol in urine by enzymatic hydrolysis/headspace gas chromatography. Chromatographia 14 507-509. 

Woodrow JE, McChesney MM, Seiber JN. 1988. Determination of methyl bromide in air samples by headspace gas chromatography. Anal Chem 60 509-512. 

Yonamine M, TawU N, Moreau RL, Silva OA. 2003. Solid-phase micro-extraction-gas chromatography-mass spectrometry and headspace-gas chromatography of tetrahydrocannabinol, amphetamine, methamphetamine, cocaine and ethanol in saliva samples. J Chromatogr B Anal Technol Biomed Life Sci 789 73. 

Varner, S.L., Breder, C.V. and Fazio, T. (1983). Determination of styrene migration from food-contact polymers into margarine, using azeotropic distillation and headspace gas chromatography, J. Assoc. Ojf. Anal. Chem., 66, 5, 1067-1073. 

C. R. Lee, F. Guivarch, C. Nguyen Van Dau, D. Tessier and A. M. Krstulovic, Determination of polar alkylating agents as thiocyanate/isothiocyanate derivatives by reaction headspace gas chromatography. Anafyir, 2003,128(7), 857-863. 

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