Headspace extraction microextraction

Headspace extraction, see also Dilution analysis Solid-phase microextraction Hemoglobin... 

Solvent Liquid/liquid extraction (LLE) Steam distillation/extraction (SDE) Solvent microextraction (SME) - SDME - LPME - DLLME Headspace-solvent-microextraction (HS-SME) - Headspace single-drop microextraction (HS-SDME) - Headspace liquid phase microextraction (HS-LPME) ... 

HSPE Headspace solvent microextraction HS extraction of volatile compounds into a single drop of solvent, which is then injected into the GC For volatile, GC-amenable compounds, particularly in water and flavor analysis... 

Keywords Degradation Multiple headspace extraction Quality control Recycling Solid-phase microextraction... 

Eisert R. and Pawliszyn J. (1997) New trends in solid-phase microextraction. Crit. Rev. Anal. Chem. 27, 103 35. Elmore J.S. and Nursten H.E. (1990) A comparison of the headspace extracts of instant and ground coffee. In Flavour Science and Technology Bessiere Y, and Thomas A.F. Eds, John Wiley Sons, New York, pp. 203-4. Elmore J.S. and Nursten H.E. (1993) The effect of 2-furanmethanethiol upon the flavour of instant coffee. Int. J. Food Sci. Technol. 28, 531 6. 

In SPME analytes can be adsorbed fl om a liquid sample, by immersion or headspace extraction, or from a solid sample, by headspace extraction using a polymer-coated fused silica fibre. Headspace solid-phase microextraction (HS-SPME) shortens the extraction time and facilitates analysis of solid samples, provided that the analytes are volatile. Pawliszyn et al. [992] have reported initial work on HS-SPME in 1993. These authors have evaluated theoretically and experimentally the equilibrium and kinetics of HS-SPME. 

Recently, SPME (solid-phase microextraction) has been applied for the adsorption thermodesorption of methylmercury by headspace extraction. The advantage of this method is that no cryogenic trapping is involved, but the disadvantage is that it is limited to relatively clean samples, as high-abundant volatile organometaUic compounds will compete with the adsorption reactions on the SPME fibre. ... 

Solid-phase microextraction (SPME) was used for headspace sampling. The FFA were extracted from the headspace with PA, Car/PDMS, and CW/DVB fibers. It was examined whether addition of salt (NaCl) and decreasing the pH by addition of sulphuric acid (H SO ) increased the sensitivity. FFA were analyzed using gas chromatography coupled to mass spectrometry in selected ion monitoring. 

Solid-phase microextraction eliminates many of the drawbacks of other sample preparation techniques, such as headspace, purge and trap, LLE, SPE, or simultaneous distillation/extraction techniques, including excessive preparation time or extravagant use of high-purity organic solvents. SPME ranks amongst other solvent-free sample preparation methods, notably SBSE (Section 3.5.3) and PT (Section 4.2.2) which essentially operate at room temperature, and DHS (Section 4.2.2),... 

Diffusive sampler Membrane extraction (MESI) Liquid-liquid extraction (LLE) Solid-phase extraction (SPE) SPE-PTV-GC Solid-phase microextraction (SPME) Headspace GC (SHS, DHS) Large-volume injection (LVI) Coupled HPLC-GC Membrane extraction (MESI) Difficult matrix introduction (DMI) Conventional solvent extraction methods 1 Pressurised solvent extraction methods Headspace GC (SHS, DHS) Thermal desorption (TD, DTD) Pyrolysis (Py) Photolysis Photon extraction (LD) Difficult matrix introduction (DMI)... 

Miniaturisation of scientific instruments, following on from size reduction of electronic devices, has recently been hyped up in analytical chemistry (Tables 10.19 and 10.20). Typical examples of miniaturisation in sample preparation techniques are micro liquid-liquid extraction (in-vial extraction), ambient static headspace and disc cartridge SPE, solid-phase microextraction (SPME) and stir bar sorptive extraction (SBSE). A main driving force for miniaturisation is the possibility to use MS detection. Also, standard laboratory instrumentation such as GC, HPLC [88] and MS is being miniaturised. Miniaturisation of the LC system is compulsory, because the pressure to decrease solvent usage continues. Quite obviously, compact detectors, such as ECD, LIF, UV (and preferably also MS), are welcome. 

Headspace solid phase microextraction (HS-SPME). With this extraction technique, it is possible to concentrate volatile compounds thus allowing their detection even at trace levels, as in the case of volatile and semi-volatile terpenes in archaeological findings [7,31]. Chapter 10 outlines how resinous materials are investigated using HS-SPME-GC/MS. 

Bicchi, C., loti, C., Rubiolo, P. and Sandra, P. (2002) Headspace sorptive extraction (HSSE), stir bar sorptive extraction (SBSE) and solid phase microextraction (SPME) applied to the analysis of roasted Arabica coffee and coffee brew. J.Agric. Food Chem. 50, 449-459. 

Abstract A relatively small number of mammalian pheromones has been identified, in contrast to a plethora of known insect pheromones, but two remarkable Asian elephant/insect pheromonal linkages have been elucidated, namely, (Z)-7-dodecen-1-yl acetate and frontalin. In addition, behavioral bioassays have demonstrated the presence of a chemical signal in the urine of female African elephants around the time of ovulation. Our search for possible ovulatory pheromones in the headspace over female African elephant urine has revealed for the first time the presence of a number of known insect pheromones. This search has been facilitated by the use of a powerful new analytical technique, automated solid phase dynamic extraction (SPDE)/GC-MS, as well as by novel macros for enhanced and rapid comparison of multiple mass spectral data files from Agilent ChemStation . This chapter will focus on our methodologies and results, as well as on a comparison of SPDE and the more established techniques of solid phase microextraction (SPME) and stir bar sorptive extraction (SBSE). 

Wei M-C, Jen J-F. Determination of chlorophenols in soil samples by microwave-assisted extraction coupled to headspace solid-phase microextraction and gas chromatography-electro-capture detection. J. Chromatogr. A 2003 1012 111-118. 

In 2003, Smith reviewed newer sample preparation techniques, including pressurized liquid extraction, solid phase microextractions, membrane extraction, and headspace analysis. Most of these techniques aim to reduce the amount of sample and solvent required for efficient extraction. 

A fourth example (P17) is from the Introduction section of the article that examines PCBs in full-fat milk. For background information, the authors outline the general four-step procedure used to determine PCBs in full-fat milk. Conventional methods used to accomplish two of these steps, extraction and cleanup, are also described. In a new paragraph, the authors introduce solid-phase microextraction (SPME), a technique that greatly simplifies this four-step process. But SPME is not recommended for complex matrixes hence, the authors motivate the topic of their current paper, headspace mode SPME (HSSPME). 

Arthur and Pawliszyn introduced solid-phase microextraction (SPME) in 1990 as a solvent-free sampling technique that reduces the steps of extraction, cleanup, and concentration to a unique step. SPME utilizes a small segment of fused-silica fiber coated with a polymeric phase to extract the analytes from the sample and to introduce them into a chromatographic system. Initially, SPME was used to analyze pollutants in water - via direct extraction. Subsequently, SPME was applied to more complex matrixes, such as solid samples or biological fluids. With these types of samples, direct SPME is not recommended nevertheless, the headspace mode (HSSPME) is an effective alternative to extracting volatile and semivolatile compounds from complex matrixes. (Adapted from Llompart et ah, 2001)... 

A new, fast, sensitive, and solventless extraction technique was developed in order to analyze beer carbonyl compounds. The method was based on solid-phase microextraction with on-fiber derivatization. A derivatization agent, 0-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBOA), was absorbed onto a divinyl benzene/poly(dimethylsiloxane) 65- xm fiber and exposed to the headspace of a vial with a beer sample. Carbonyl compounds selectively reacted with PFBOA, and the oximes formed were desorbed into a gas chromatograph injection port and quantified by mass spectrometry. This method provided very high reproducibility and linearity When it was used for the analysis of aged beers, nine aldehydes were detected 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, pentanal, hexanal, furfural, methional, phenylacetaldehyde, and (E)-2-nonenal. (107 words)... 

Objective. To date, there is no simple or rapid procedure for testing PCBs in milk. Headspace solid-phase microextraction (HSSPME) is a promising approach, but only a few works have applied this technique to milk (1, 2). Here, we present a simple and rapid saponification-HSSPME procedure for extracting PCBs from milk. (119 words)... 

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