• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.515-525
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• 2007

In this study, various techniques for measurement and analysis of PAHs in the ambient air were verified in order to select a more reliable method. Sampling and analysis of PAHs were done by the EPA TO-13a method. QA/QC of the measurement was conducted to minimize errors in sampling and analyzing processes. The linearity of calibration curve of the PAH standards was good ($R^2{\geq}0.99$). Audit accuracy was evaluated using 5 internal standards of PAHs ($Naphthalene-d_8,\;Acenaphthene-d_{10},\;Phenanthrene-d_{10},\;Chrysene-d_{12},\;Perylene-d_{12}$). Relative standard deviations of the internal standard of the PAHs were ranged from 6.22% for $acenaphthene-d_{10}$ to 8.11% for $chrysene-d_{12}$. To evaluate the surrogate recoveries, two field surrogate standards of PAHs ($fluoranthene-d_{10},\;benzo(a)pyrene-d_{12}$) and two extract surrogate standards of the PAHs ($fluorene-d_{10},\;pyrene-d_{12}$) were spiked into all samples before field sampling and sample extraction, respectively. Recoveries of field the surrogate standards ranged from $80.4{\pm}12.2%$ for $fluoranthene-d_{10}$ to $66.2{\pm}12.8%$ for $benzo(a)pyrene-d_{12}$. Extraction recoveries of the surrogate standards ranged from $70.4{\pm}10.2%$ for $fluorene-d_{10}$ to $77.6{\pm}10.8%$ for $pyrene-d_{10}$. The detection limit of benzo(a)pyrene among 16 PAHs standards for quantitation was 20 pg.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.806-808
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• 2004

A gas chromatography/mass spectrometric assay method has been developed for the simultaneous determination of icing inhibitors, ethylene glycol monomethyl ether and diethylene glycol monomethyl ether in ground water contaminated with JP-8. Ethylene glycol monobutyl ether and ethylene glycol monoethyl ether were used as the internal standard and surrogate, respectively. 100 mL of ground water was extracted twice with 20 mL of methylene chloride. The extract was concentrated to dryness, dissolved with 100 ${\mu}$L of methanol and analyzed by GC-MS (SIM). The use of an Innowax column gave the peaks good chromatographic properties, and the extraction of these compounds from samples gave recoveries of about 50% with small variations. The method detection limits of the target compounds were in a range of 0.5-0.8 ng/mL in ground water.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.428-437
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• 2023

A simultaneous analytical method was developed and validated for the analysis of prohibited fluoroquinolone (FQ) antibiotics including norfloxacin, ofloxacin, and pefloxacin, released by aquaculture in seawater and effluents. The samples were filtered, and extracts were obtained using a solid phase extraction cartridge with methanol (MeOH). The extracts were concentrated, and analyzed using ultra-performance liquid chromatography-tandem mass spectrometry. Two different columns and four different mobile phases were compared to achieve optimal separation and sensitivity for target compounds. Typical validation parameters including linearity, recovery of surrogate standard, instrument detection limit (IDL), limit of quantification (LOQ), and method detection limit (MDL) were evaluated. The linearity of calibration curves was over 0.999. Recoveries of surrogate ranged from 87.6% to 113%. The LOQ of target compounds was approximately 3-8 times lower than those reported in previous studies. The IDL and MDL were 0.06-0.57 and 0.06-0.37 ng/L, respectively. Seven effluent samples collected from an aquaculture located in Jeju were analyzed; however, not all target compounds were detected in the samples, suggesting that the banned antibiotics were not used. Overall, this established method was able to simultaneously analyze the three FQ antibiotics, and may be useful for monitoring prohibited antibiotics in the fishery industry.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.196-200
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• 2003

A gas chromatography/mass spectrometric assay method was developed for the simultaneous determination of ethylene glycol monomethyl ether (EGME) and diethylene glycol monomethyl ether (DEGME) in spilled aviation fuels. Ethylene glycol monobutyl ether (EGBE) and ethylene glycol monoethyl ether (EGEE) were used as internal standard and surrogate, respectively. The sample preparation consists of back-extraction with 7 mL of methylene chloride after extraction of 50 mL of fuel with 2 mL of water. The extract was concentrated to dryness and dissolved with 100L of methanol and analyzed by CC-MS (SIM). The peaks had good chromatographic properties by using semi-polar column and the extraction of these compounds from fuel also gave high recoveries of 75 and 85 % with small variations for EGME and DEGME, respectively. Method detection limits were 1.3 ng/mL for EGME and 1.0 ng/mL for DEGME in spilled fuel. The method may be useful for fuel-type differentiation between kerosene and JP-8, which may originate from the storage tank.