• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.191-191
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• 1999

A Purge & Trap Concentrator was used to analyze various volatile organic compounds(VOCs) in wat-er. The object of this study was to observe the purge efficiency of 40 VOCs in water according to the change of parameters (purge time drypurge time sample temperature) and to determine the optimum condition for VOCs using the purge & Trap concentrator interfaced with a narrow capillary connected to a gas chromatography/mass spectrometry. The optimum condition of purge and trap is as follows: purge time at 11min drypurge time at 5min sample temperature at 6$0^{\circ}C$ at constant purge flow (40mol/min) constant desorption flow(20ml/min) desorption temperature(2$25^{\circ}C$) and desorption time (1min) At this analytical condition the detection limits of VOCs was in the range of 0.1~0.5$\mu$g/ml and the purge efficiency of each compound was over 70%.

• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.171-178
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• 2001

A Purge and Trap Concentrator has been used to analyze various volatile organic compounds in water, operating several parameters affecting the extraction efficiencies of these compounds. The object of the present study was to observe the purge efficiencies of 40 volatile organic compounds (VOCs) in water, according to the change of parameters (purge time, dry purge time, sample temperature), and to determine the optimum condition of analysis of VOCs. The Purge and Trap Concentrator was interfaced with a narrow capillary connected to a gas chromatography mass spectrometer. At this condition, the detection limits of VOCs were in the range of 0.1-0.5 ㎍/L.

• Journal of the Korean Chemical Society
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• v.62 no.6
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• pp.453-457
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• 2018

• Journal of the Korean Chemical Society
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• v.39 no.8
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• pp.635-642
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• 1995

Improved sample introduction system has been investigated for the determination of volatile organic compounds in water using a purge & trap preconcentration apparatus and a capillary gas chromatography/mass spectrometry. The present limitations associated with the moisture control module and cryorefocusing system suggested by EPA were discussed. To solve the problems such as improper separation of peaks due to the adsorption of water and contamination of purge & trap system, a more efficient connection system between the purge & trap apparatus and the gas chromatograph was introduced and the optimum operational conditions were suggested. A carbopack B/carboxen 1000 and 1001 trap was used for the purge & trap procedure and a custom made crosslinked dimethyldiphenylpolysiloxane capillary column was used for the separation of compounds. Accuracy and precision of the method suggested in this report were examined and the method detection limit of each compound was proposed for the simultaneous determination of 54 volatile organic compounds in water.

• Analytical Science and Technology
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• v.14 no.5
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• pp.392-399
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• 2001

The analysis of n-butylbenzene and 1,2-dibromo-3-chloropropane (DBCP) as volatile organic compounds in biota samples was performed by gas chromatography/mass spectrometry-selected ion monitoring mode. The target compounds, n-butylbenzene and DBCP, in biota samples were extracted by headspace solid phase microextraction (SPME) with $100{\mu}m$ polydimethyl siloxane (PDMS) fiber and purge & trap method. The extraction recoveries of these compounds obtained by SPME was 85.8% for n-butylbenzene and 92.4% for DBCP, respectively. Each value of method detection limit were $0.15{\mu}g/kg$ and $0.05{\mu}g/kg$, respectively. While in the case of purge & trap method, the extraction recovery was 115.2% for n-butylbenzene, 80.9% for DBCP and method detection limit were $0.04{\mu}g/kg$ and $0.70{\mu}g/kg$, respectively. The extraction yields and detection limits of these compounds obtained by purge & trap were equivalent to those by SPME.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.738-741
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• 2006

Volatile flavor compounds in commercial sterilized milk were analyzed and identified by static headspace, purge-and-trap, and solid-phase microextraction (SPME) methods. About 20 volatile compounds were identified by GC/MS, and aldehydes and ketones were the most distinctive and abundant compounds. Static headspace analysis allowed the identification of only the most abundant compounds, such as acetone. Five ketones (acetone, 2-butanone, 2-pentanone, 2-heptanone, 2-nonanone), four aldehydes (2-methylbutanal, pentanal, hexanal, benzaldehyde) and dimethyl sulfide, all of which were responsible for off-flavor in milk, were found by the purge-and-trap and SPME methods. The two methods differed little in their release of these compounds, but they yielded different amounts in the extraction.

• Journal of Environmental Health Sciences
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• v.20 no.4
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• pp.53-59
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• 1994

Since trihalomethanes (THMs) and other volatile organic compounds (VOCs) were detected and measured in drinking water supplies in 1974, because of the frequent occurrence of these compounds and the potential health hazard they pose, several methods for detecting VOCs have been developed. The most widely accepted method for the analysis of THMs and other VOCs is a purgeand-trap method. In the analysis of VOCs by purge-and-trap,there are several factors which may give rise to errors. Some of the factors to be considered are purge time, carryover effect, cryofocusing temperature, and trap desorption temperature. In this study,many aspects of purge-and-trap were investigated. Understanding the sources of error makes it possible to adapt the analysis parameters to compensate for such effects.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.78-83
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• 2005

Purge & Trap method was applied to perform more simple and rapid detection for analysis of volatile flavor compounds in milk. Maximal sampling of 30 mL milk for glass flask sparger was treated by He gas purging for 2 hours. Reported major volatile compounds were detected by GC-MS after 2 hours absorption and desorbed from Purge & Trap equipped with Tenax trap. Volatile flavor compounds were analyzed by Purge & Trap and GC-MS to investigate the changes of flavor components in milk between raw and deodorized milk. Fourteen volatile compounds including acetaldehyde, ethanol, 2-propanone, dimethyl sulfide, isobutanal, 3-methyl 2-butanone, 2-butanone, 3-methyl butanal, pentanal, 3-hydroxy-2-butanone, methyl disulfide, hexanal, and 2 others were detected. Six compounds such as ethanol, dimethyl sulfide, pentanal, 3-hydroxy-2-butanone, and methyl disulfide were completely eliminated after deodorization treatment. Four compounds such as 3-methyl 2-butanone, 2-butanone, 3-methyl butanal, and an unknown compound 81 (M/sup +/) were also decreased after raw milk was deodorized. The other four compounds such as acetaldehyde, 2-propanone, hexanal, and an unknown compound (M/sup +/) were not decreased.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.374-378
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• 2005

A diffusion - precipitation method was developed to determine acid volatile sulfide (AVS) concentrations in freshwater sediments. This method uses silver nitrate as a sulfide trap solution and the concentration of trapped sulfide is determined gravimetrically. The proposed diffusion - precipitation method is more rapid and less expensive than previously developed purge- and - trap methods. Spiked sodium sulfide recoveries using this method $(97\~120\%)$ were similar with a previously developed diffusion - absorption method $(93.8\~115\%)$ and about $20\%$ greater than a previously developed purge-and-trap method $(74.6\~105\%)$. Detection limit of this method $(0.1\;{\mu}mole\;S\;g^{-l})$ was comparable with that of diffusion-absorption method $(0.06\;{\mu}mole\;S\;g^{-l})$ and purge-and-trap method $(0.05\~0.5\;{\mu}mole\;S\;g^{-l})$.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.260-265
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• 2004

Volatile components of pine needle(Pinus densiflora S.) were isolated by purge & trap headspace technique and analyzed by gas chromatography-mass spectrometry(GC-MS). And then volatile components were extracted for 2 hr and 20 hr at the two different temperature settings: room temperature and 60$^{\circ}C$. A total of 61 volatile components were identified by the four different conditions. These compounds are classified into six categories in terms of chemical functionality: 35 hydrocarbons, 16 alcohols, 4 carbonyls, 2 esters, 1 acid and 3 ethers. The major components were ${\alpha}$-pinene(1.5～15.7%), ${\beta}$-myrcene(13.2～15.6%), ${\beta}$-phellandrene(l2.0～16.0%) and cis-3-hexenol(4.0～18.3%). In the comparison of the four extraction conditions, longer extraction can be effective to extract components that have a high boiling point, but proved useless in obtaining low boiling point components. As a result of these experiments under the four different conditions, the 20 hr extraction at room temperature appeared to be the most optimized condition for the analysis of volatile compounds by using the purge & trap headspace technique.