• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1405-1411
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• 2006

The presence and content of residual hexane in the olive oils were studied. Total 41 olive oils of imported and domestic brands, which were labeled as extra virgin and refined (mixed), were collected from the market. For analysis, electronic nose and headspace SPME-GC/MS were used. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of olive oils against the different concentrations of hexane. From the results, it is assumed that the contents of residual hexane in the collected olive oils were below 5 ppm. For Qualitative and quantitative analysis of hexane, polydimethylsiloxane (PDMS) fiber was employed for SPME-GC/MS. In the results, the peak of residual hexane was detected in 8 samples from 41 olive oils. But the detected level was no more than 1 ppm that is under the regulation limit (5 ppm) by Korea Food Additive Code.

• Analytical Science and Technology
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• v.20 no.3
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• pp.237-245
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• 2007

The presence of benzene in 31 products of vitamin drinks purchased from 20 retail outlets was determined using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). The sample (25 ml) was stirred at 1200 rpm for 4 min using a magnetic bar with a $100{\mu}m$ SPME fiber as an adsorbent for benzene which was then desorbed from the fiber for 1 min in the GC injector. Quantitation was achieved using the standard addition method. The limit of detection was determined as 0.56 ng/ml and over a concentration range 0-40 ng/ml the coefficient of correlation was greater than 0.999. The concentration of benzene in the drinks examined was in the range not detectable to 47.35 ng/ml. Benzene was detected in 15 of the drinks with concentration in 5 of them greater than 10 ng/ml which is the limit set for the presence of benzene in the Drinking Water Regulations. The concentrations of benzene in the 5 drinks which exceeded the limit of 10 ng/ml were 16.99, 35.14, 16.03, 47.35 and 14.28 ng/ml respectively.

• 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 the Korean Society of Tobacco Science
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• v.32 no.2
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• pp.77-87
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• 2010

Traditional simultaneous distillation extraction(SDE) and solid-phase micro extraction(SPME) methods using GC/MS were compared for their effectiveness in the extraction of volatile flavor compounds from different tobacco leaves types(flue-cured, burley, oriental). The major volatile flavor compounds of flue-cured and burley tobacco were similar such as neophytadiene, solanone, megastigmatrienone isomers, ${\beta}$-damascenone and ${\beta}$-ionone. On the other hand, volatile flavor compounds such as norambreinolide, sclareolide were specifically identified in oriental tobacco. Each method was used to evaluate the responses of some analytes from real samples and standards in order to provide sensitivity comparisons between two techniques. Among three types of SPME fibers such as PDMS(Polydimethylsiloxane), PA(Polyacrylate) and PDMS/DVB (Polydimethylsiloxane/Divinylbenzene) which were investigated to determine the selectivity and adsorption efficiency, PDMS/DVB fiber was selected for the extractions of the volatile flavor compounds due to its effectiveness. The qualitative analysis showed that the total amount of volatile flavor compounds in SDE method(130 species) was much more than that in SPME method(85 species). SPME method was more efficient for all the highly volatile compounds than SDE method, but on the other hand, low-volatile compounds such as fatty acids or high-molecular hydrocabons were detected in SDE method. SPME method based on a short-time sampling can be adjusted to favor a selected group compounds in tobacco. Furthermore this results could be used to estimate the aroma characteristics of cigarette blending by using a different type of tobacco with more effectiveness and convenience.

• Analytical Science and Technology
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• v.21 no.4
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• pp.259-271
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• 2008

The analytical method of extracting compounds from human blood to examine accumulated organochlorine pesticides (OCPs) has been widely used the traditional liquid-liquid extraction (LLE) method and solid-phase extraction (SPE) method, yet these methods have certain limitations in purification and usafe of a large amount of sample. In order to overcome the se problems reside in these, solid-phase microextraction (SPME), known as a highly efficient extration method with less samples and relatively simple, was employed to collect 18 different kinds of OCPs in blood as extraction method in this study. To optimize extraction method, we examine various experimental SPME-parameters such as adsorption (fiber type, adsorption time, adsorption temperature, salting out effect), and desorption (desorption time, desorption temperature etc.). From the experimental results, the optimal conditions are as follows: fiber was polyacrylate with $85{\mu}m$, adsorption time was for 5 min, adsorption optimum temperature was at $280^{\circ}C$, and salting out effect was NaCl with 0.1 g. MDL, precision and accuracy was in the ranges of 0.05~0.20 ng/mL, 5.59~13.39%, respedively, and accuracy was -0.5% ~24.5% for all OCPs.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.271-279
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• 2004

The aroma component of Hallabong peel has been characterized by GC-MS with two different extraction techniques: solid-phase trapping solvent extraction (SPTE) and headspace solid-phase microextraction (HSSPME). Aroma components emitted from Hallabong peel were compared with those of other citrus varieties: lemon, orange and grapefruit by SPTE and GC-MS. d-Limonene (96.98%) in Hallabong was the main component, and relatively higher peaks of cis- ${\beta}$-ocimene, valencene and -farnesene were observed. Other volatile aromas, such as sabinene, isothujol and ${\delta}$-elemene were observed as small peaks. Also, principal components analysis was employed to distinguish citrus aromas based on their chromatographic data. For HSSPME, the fiber efficiency was evaluated by comparing the partition coefficient ($K_{gs}$Kgs) between the HS gaseous phase and HS-SPME fiber coating, and the relative concentration factors (CF) of the five characteristic compounds of the four citrus varieties. 50/30 ${\mu}$m DVB/CAR/PDMS fiber was verified as the best choice among the four fibers evaluated for all the samples.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.373-379
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• 2005

The volatile components of Pinus densiflora needles were studied by gas chromatography-mass spectrometry(GC-MS), using seven kinds of solid phase microextraction (SPME) fibers, seven in SPME fibers: 100 ${\mu}m$ PDMS, 65 ${\mu}m$ PDMS/DVB, 65 ${\mu}m$ SF-PDMS/DVB, 85 ${\mu}m$ PA, 75 ${\mu}m$ CAR/PDMS, 65 ${\mu}m$ CW/DVB and 50/30 ${\mu}m$ DVB/CAR/PDMS fibers. A total of 40 components were identified by using the seven different SPME fibers. The identified components were classified, according to their functionalities, as follows: 26 hydro-carbons, 7 alcohols, 4 carbonyl compounds, and 3 esters. The major volatile components of Pinus densiflora needles identified by these SPME fibers were $\alpha$-pinene ($1.7\~21.7\;{\mu}g/g$), $\beta$-myrcene ($2.0\~20.1\;{\mu}g/g$), $\beta$-phel-landrene ($4.6\~22.8\;{\mu}g/g$), $\beta$-caryophyllene ($6.7\~26.0\;{\mu}g/g$) germacrene D ($1.1\~11.9\;{\mu}g/g$). In the comparison of the seven SPME fibers, PDMS appeared to be the most suitable fiber for the analysis of hydrocarbon compounds and CAR/DPMS, PDMS/DVB, CW/VB and DVB/CAR/PDMS are shown to be optimal for analysis of the alcohols and carbonyl compounds.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.59.1-59.1
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• 2015

In the Linford group at Brigham Young University we have recently developed three new sets of materials for three different areas of separations science: thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and solid phase microextraction (SPME). First, via microfabrication we have grown patterned carbon nanotube (CNT) forests on planar substrates that we have infiltrated with inorganic materials such as silicon nitride. The coatings on the CNTs are conformal and typically deposited in a process like low pressure chemical vapor deposition. The resulting materials have high surface areas, are porous, and function as effective separation devices, where separations on our new TLC plates are typically significantly faster than on conventional devices. Second, we used the layer-by-layer (electrostatically driven) deposition of poly (allylamine) and nanodiamond onto carbonized poly (divinylbenzene) microspheres to create superficially porous particles for HPLC. Many interesting classes of molecules have been separated with these particles, including various cannabinoids, pesticides, tricyclic antidepressants, etc. Third, we have developed new materials for SPME by sputtering silicon onto cylindrical fiber substrates in a way that creates shadowing of the incoming flux so that materials with high porosity are obtained. These materials are currently outperforming their commercial counterparts. Throughout this work, the new materials we have made have been characterized by X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, scanning electron microscopy, transmission electron microscopy, etc.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.890-896
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• 2018

The aim of this study was to determine volatile flavor compounds in Shingo pear juice. Volatile flavor compounds were analyzed using solid-phase micro-extraction (SPME) - gas chromatography-mass spectrometry (GC-MS). The effect of inorganic salts solution on the extraction ability of the SPME fiber was treated by adding saturated $CaCl_2$ solution at the ratio of 1:20 (v/v) after 0, 60, 120 min of preparing pear juice, respectively. As a result, a total of 22 volatile compounds were identified in Shingo pear juice. Ethyl acetate was found to be the most abundant volatile compound ($13.36{\sim}19.61{\mu}g/kg$), followed in order by hexanal, ethyl hexanoate, ethyl 3-(methylthio)-2-propenoate, ethyl octanoate and 2-hexenal. Total contents of volatile flavor compounds were $31.07{\mu}g/kg$ (control), $40.93{\mu}g/kg$ (0 min), $27.62{\mu}g/kg$ (60 min) and $26.32{\mu}g/kg$ (120 min). This result indicated that the addition of saline solutions could inhibit the enzymatic reaction of volatile flavor compounds effectively when treated as soon as juice preparation.