• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.248-251
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• 2008

일반적으로 phthalate esters의 전처리방법에는 액액추출법(liquid-liquid extraction), 고상추출법(Solid-phase Extraction, SPE), 고상미세추출법(Solid-phase micro extraction, SPME) 등의 분석방법이 있다. 그 중에서 본 연구에서는 SPE를 이용하여 간편하고 정확성이 높으며, 적은 양의 유기용제를 사용하여 전처리함으로써 2차적인 환경오염을 줄일 수 있다는 점에서 다른 전처리 방법보다 유용하다고 할 수 있다. 검출감도 측면에서 phthalate esters의 경우는 구조적으로 안정적인 편이나 페놀류의 경우 hydroxy group 때문에 GC/MS 분석시 유도체화 과정이 필수적인데 이번 연구에서 사용한 BSTFA/TMCS는 비교적 쉽고 빠르게 유도체 화할 수 있다는 이점이 있다. 더 많은 연구가 필요하겠지만 앞서서의 결과에서도 알 수 있듯이 전반적으로 검출한계가 0.05$\sim$0.5 $\mu$g/L 정도로 높고, 4-nonyl phenol을 제외하고 80% 이상의 양호한 회수율을 나타낸 것으로 미루어 보아 phthalate esters, phenols의 효율적인 동시분석이 가능함을 알 수 있다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.272-274
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• 2008

일반적으로 프탈레이트 에스테르의 전처리방법에는 액액추출법(Liquid Liquid Extraction, LLE), 고상추출법(Solid Phase Extraction, SPE), 고상미세추출법(Solid Phase Micro Extraction, SPME) 등의 분석방법이 있다. 그 중에서 본 연구에서는 간편하고 정확성이 높은 SPE를 이용하였으며, 적은 양의 유기용제를 사용하여 전처리함으로써 2차적인 환경 오염을 줄일 수 있다는 점에서 다른 전처리 방법보다 유용하다고 할 수 있다. 또한 프탈레이트 에스테르의 경우는 구조적으로 안정적인 편이나 페놀류의 경우 hydroxy group 때문에 GC/MS 분석시 유도체화 과정이 필수적이나 이번 연구에서는 HPLC를 이용하므로 별도의 유도체화의 번거로움 없이 바로 분석할 수 있는 이점이 있다. 더 많은 연구가 필요하겠지만 앞서서의 결과에서도 알 수 있듯이 전반적으로 검출한계가 0.1$\sim$0.5$\mu$g/L 정도로 높고, 82% 이상의 양호한 회수율을 나타낸 것으로 미루어 보아 극미량 분석이 아닌 이상, 산업체에서 HPLC의 이용이 더욱 유리할 것이라고 사료된다.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.636-647
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• 2016

Magnetite nanoparticles ($Fe_3O_4$ NPs) were synthesized by co-precipitating method under optimized condition. The $Fe_3O_4$ NPs coated with sodium dodecyl sulfate-thenoyltrifluoroacetone ($Fe_3O_4$ NPs-SDS-TTFA) were then exerted as the magnetic solid phase extraction (MSPE) adsorbent for the extraction process prior to introducing to a flame atomic adsorption spectrometry (FAAS). The synthesized $Fe_3O_4$ NPs-SDS-TTFA were applied for the extraction of Pb(II) ions from different water samples. The characterization studies of nanoparticles were performed via scanning electron microscopy-energy dispersive micro-analysis (SEM-EDAX), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) techniques. The substantial parameters affecting the extraction efficiency were surveyed and optimized. A dynamic linear range (DLR) of $10-400{\mu}g\;L^{-1}$ was obtained and the limit of detection (LOD, n=7) and relative standard deviation (RSD%, n= 6, $C=20{\mu}g\;L^{-1}$) were found to be $2.3{\mu}g\;L^{-1}$ and 1.9%, respectively. According to the results, the proposed method successfully applied for the extraction of Pb(II) ions from different environmental water samples and satisfactory results achieved.

• Journal of Environmental Science International
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• v.6 no.3
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• pp.277-283
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• 1997

SPME deuce was applied to determine the THM in an aqueous solution. The 6 kinds of THM was quantitatively detenuned by using GC-ECD which has the sample eutracted on the SPME fiber from an aqueous solution for 10 min. The THM components were well separated from $CHCl_3$ to the last $CHBr_3$ UHh 13 mons at the condition. 6 kinds of the volatile halogenated organic compounds: $CHCl_3$, $CHBrCl_2$, $CHBrtCl_2$, $CHCl_3$, $C_2Cl$. and $CHBr_3$, showed well defirled calibration graph with good llnearlty from a few ppb level up to several tens of pub concentration. $CHBr_2Cl$ and $C_2C1_4$ were detected from a few samples among the 10 of river samples. CHCl3, however, was detected In 4 sea water samples with the highest of 10 ppd among the pouuted 6 positions. Trace level of $CHBr_2Cl$ and few pub level of $CHBr_3$ were also detected at the other two sample stations. Most of the 13 rain water samples collected from 6 sampling stations were contained ppd level of $CHCl_3$, and also $CHBr_2Cl$, and C_2Cl_4$ were only detected at trace level at a few rain samples among them. We could recognize the fact that our Ut and water enoronment has already been contaminated by certain volatile halogenated organic compounds through this study.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2001.10a
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• pp.171-174
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• 2001

Solid phase micro-extraction (SPME), a solvent-free, rapid and inexpensive method for the extraction of organic compounds from aqueous sample matrices, was evaluated for determination of the 120 pesticides in vegetables such as crown daisy, perilla leaf, leafy lettuce and to mato. The analysis conditions were chosen for the SPME method: 15 min of immersion of the PDMS fiber in 10 ml of the solution with stirring at 1,000 rpm. The recovery tests were carried out in triplicate. The range of recoveries was 0-142% for organochlorine pesticides and $4.9\sim200\%$ for organophosphorus pesticides. The recoveries were very low in the pesticide groups with low solubility in water. The recoveries became lower in proportion to the interference materials in vegetables. The recovery in tomato was relatively higher than that in perilla Ie af and crown daisy. The recovery values obtained by SPE and SPME were compared. In leaf y lettuce, recovery obtained by SPE method ranged from $58.1\%\;to\;136.1\%$ and recovery by SPME ranged from $9.6\%\;to\;176.3\%$ In organophosphorus pesticides. The recovery in SPME method was satisfactory with $136\%$ for ethoprophos, $119\%$ for methidathion and $113\%$ for diazinon. Meanwhile, recovery of EPN, phenthoate and 2,4-DDT revealed relatively low value of $38\%,\;41\%\;and\;3.4\%,$ respectively. However, most of pesticides applied to SPME method sho wed constant recovery and precision. From these results, it can be concluded that solid phase micro-extraction might be an appropriate method for the screening test of pesticides in vegetables.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1693-1701
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• 2014

A rapid and simple method for the quantitative determination of volatile fatty acids (VFAs; propionic acid, n-butyric acid, i-valeric acid and n-valeric acid) and indoles (phenol, p-cresol, 4-ethyl phenol, indole and skatole) in pig slurry and dog excrement using solid-phase micro-extraction (SPME) coupled to gas chromatography was evaluated. $50/30{\mu}m$ DVB/CAR/PDMS (Divinylbenzene/Carboxen/Polydimethylsiloxane) fiber was used to extract the target compounds in aqueous media. Sample amount and adsorption time was standardized for the routine analysis. Detection limits were from 0.11 to $0.15{\mu}gL$ for VFAs and from 0.12 to $0.28{\mu}gL$ for indoles and the correlations observed ($R^2$) were 0.975~1.000. This method was applied to the pig slurry, fertilizer, compost and dog excrement. In nearly all cases, the indoles were detected in concentrations of higher than their limits of detection (DOLs). But the VFAs in swine manure were below their DOLs.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1447-1454
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• 2010

In this study, the detection limits of lower fatty acids in air were investigated by using Dynamic SPME(Solid Phase Micro-Extraction), i.e. improved Head Space - SPME method(HS-SPME). This Dynamic SPME, called SPDE(Solid Phase Dynamic Extraction), is the analytical method for volatile compounds in air with the extraction by using a stainless steel needle of which inner surface is coated with adsorption material and following the gas chromatographic analysis by inserting the needle into a injection port of GC and subsequently, desorption of the volatile compounds into a gas-chromatographic column. Extraction was carried out by passing the sample air through the needle with a suction pump which has been used for a detection tube. The result of measurement for the 6 lower fatty acids showed that the detection limits ranged from 0.10 ppm to 0.44 ppm and the linear correlation coefficients were over 0.99. Relative standard deviations obtained from 5 analytical repetition of a ca. 1.6 ppm standard mixture were in the range of 1.87%~2.47%. This method has been shown to be a adequate for the measuring C2~C5 fatty acids in air in the concentrations of over several hundreds ppb.

• Mass Spectrometry Letters
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• v.8 no.1
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• pp.18-22
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• 2017

Products containing any one or more of 26 fragrance allergens likely to cause contact allergies, are required under the 2008 domestic cosmetic law to be labeled when their concentrations exceed a certain range. This study focuses on the comparison and development of analytical methods based on headspace-solid phase micro extraction (HS-SPME) and liquid-liquid extraction (LLE) methods followed by GC-MS/MS for 24 of the fragrance allergens excepting for two natural materials in water samples. Using the developed HS-SPME method, 15 of the 24 fragrance allergens were analyzed and 9 compounds which have relatively low $logK_{OW}$ values (below about 2.5) were not extracted, and the correlation coefficient ($r^2$) of the calibration curve for quantification showed linearity of 0.9969 or more, and the method detection limits (MDL) and the limits of quantification (LOQ) were $0.078{\sim}0.582{\mu}g/L$ and $0.261{\sim}1.940{\mu}g/L$, respectively. In the case of using the optimized LLE method, all 24 fragrance allergens were analyzed, and the correlation coefficient ($r^2$) of the calibration curve for quantification showed linearity of 0.9957 or more, MDL and LOQ were $0.020{\sim}0.138{\mu}g/L$ and $0.065{\sim}0.440{\mu}g/L$, respectively.

• Analytical Science and Technology
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• v.7 no.3
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• pp.421-425
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• 1994

A micro-high performance liquid chromatography(Micro-HPLC) techniquie with solid phase extraction was reported which detected carbendazim and carbaryl at picogram levels. They were separated on microbore packed $C_{18}$ column($1.0mm\;I.\;D{\times}150mm$, $d_f=5{\mu}m$) using a 50% methanol mobile phase and detected at UV 220nm(${\alpha}=2.94$, $R_s=4.71$), while they were not resolved on analtical HPLC system(${\alpha}=1.27$, $R_s=0.76$). The detection thresholds of carbendazim and carbaryl were 0.5ng and 0.1ng on Micro-HPLC, therefore Micro-HPLC system was 20~40 told more sensitive than anayltical HPLC system. Sep-Pak $C_{18}$ catridge was found to be efficient in enriching carbendazim and carbaryl from dilute aqueous solution with 97.0% and 97.8% recoveries of them. The Sep-Pak $C_{18}$ catridge followed by the Micro-HPLC had been applied to the quantitative analysis of carbendazim and carbaryl in spiked juices and a commercial drinking water.

• Journal of the Korean Society of Tobacco Science
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• v.35 no.1
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• pp.7-12
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• 2013

A Solid-phase micro extraction(SPME) was evaluated as a tool for headspace sampling of tobacco samples. Several experimental parameters (sampling temperature, pH, and type of SPME fibers) were optimized to improve sampling efficiency in two aspects ; maximum adsorption and selective adsorption of volatile organic acids onto SPME fibers. Among four types of SPME fibers such as PDMS(Polydimethylsiloxane), PA(Polyacrylate), Car/PDMS (Carboxen/Polydimethylsiioxane) and PDMS/DVB(Polydimethylsiioxane/Divinylbenzene) which were investigated to determine the selectivity and adsorption efficiency. A variety of tobacco samples such as flue cured, burley and oriental were used in this study. The effect of these parameters was often dominated by the physical and chemical nature (volatility, polarity) of target compounds. This method allowed us to make important improvements in selectivity and sensitivity. The Car/PDMS fiber was shown to be the most efficient at extracting the 10 selected volatile organic acids. The parameters were optimized: $80^{\circ}C$ adsorption temperature, 30 min of adsorption time, $240^{\circ}C$ desorption temperature, 1 min of adsorption time.