• 분석과학
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• 제15권3호
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• pp.248-255
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• 2002

The contents of ${\alpha}$-, ${\beta}$-, ${\gamma}$-, and $\delta$-tocopherols in sesame oils were determined by high performance liquid chromatography with UV detection. ${\alpha}$-Tocopherol contents ranged from 10.28 to 19.79 mg/g oil, ${\beta}$-tocopherol contents from 8.22 to 20.10 mg/g. However, both ${\gamma}$- and $\delta$-tocopherol were less than 1.49 mg/g or not detected. ${\gamma}$-Tocopherol was not detected from both unroasted white and black sesame seed oils. Significantly higher level of tocopherol in sesame oil than other oils is an evidence of the reason why it is highly stable and prevents oxidation. The tocopherol composition for twenty sesame oils was classified by using principal component analysis.

• 분석과학
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• 제8권4호
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• pp.753-758
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• 1995

Thermal desorption/gas chromatography/mass selective detection method using Tenax cartridges for the determination of gaseous polycyclic aromatic hydrocarbons(PAH) is described. Glass fiber filter can collect only PAH in particulate. Gaseous PAH may penetrate the filter. Glass cartridge packed Tenax-GC was uses fur adsorption of gaseous PAH. The air of inhalation zone was collected fur 2-10 hours. Cartridges were thermally desorbed in the reverse direction to sample flow. The desorption conditions were as follows; desorption temperature; $300^{\circ}C$; desorption time; 20min; column head pressure; 30psi; inlet split vent; closed during desorption.

• 분석과학
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• 제8권4호
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• pp.465-468
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• 1995

Matrix assisted laser desorption ionization in mass spectrometry is a fast and accurate method to determine the molecular weight of natural and synthetic polymers. Unknown peptides such as elastase inhibitor and $\small{D}$-hydantoinase were analyzed using sinapinic acid as matrix and their molecular weights were compared with the results from protein sequencer and gel filtration chomatography, respectively. Synthetic polymers such as polyethyleneglycol, polypropyleneglycol, polydimethylsiloxane, and polystyrene were analyzed using matrices such as 2,5-dihydroxybenzoic acid, 4-hdroxyazobenzenecarboxylic acid, and 2-nitrophenyl octyl ether. Average molecular weights of polystyrene were compared with molecular weights by gel permeation chromatography.

• 한국대기환경학회지
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• 제18권6호
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• pp.475-485
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• 2002

An analytical method was investigated for the meaiiurement of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) concentrations in air samples. Procedures required for column chromatographic clean up. silicagel (stage I) and gel permeation chromatography (stage II), were discussed. Identification and quantification of PCBs and OCPs were performed using a combination of gas chromatography/mass spectrometry/ selected ion monitoring. Recovery tests calculated from six samples are 68∼137% for PCBs and 58∼130% for OCPs except for endrin aldehyde. Instrumental detection limits determined for the PCBs and OCPs varied from 0.05 to 0.18 pg/m3 and from 0.71 to 16.82 pg/㎥, respectively. The method has been applied to the analysis of air samples collected at Ansung city, Kyonggi province, Korea. This method may serve as a screening protocol for the simultaneous determination of PCBs and OCPs in air.

• Food Science and Biotechnology
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• 제18권6호
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• pp.1515-1518
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• 2009

The objective of this study was to compare 3 extraction methods including, solid phase extraction (SPE), acetonitrile extraction, and methanol extraction, for their usefulness as extraction methods to determine capsaicinoids. The determination of capsaicinoids in the extracts was carried out on a reverse-phased high performance liquid chromatography (HPLC) using a fluorescence detector. Three extraction methods, i.e., SPE, acetonitrile extraction, and methanol extraction were compared for the quantification of capsaicinoids using raw peppers and pepper powder. The highest analytical values were observed using methanol extraction and the lowest values using SPE. Also, the analytical method validation parameters such as accuracy, precision, limit of detection, limit of quantitation, and specificity were calculated to ensure the method's validity. This method provides a fast and accurate approach for the determination of capsaicinoids in peppers.

• Journal of Applied Biological Chemistry
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• 제42권4호
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• pp.191-196
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• 1999

A multiresidue analytical method was developed for eight acaricides including benzoximate, clofentezine, fenazaquin, fenothiocarb, fenpyroximate, hexythiazox, pyridaben, and tebufenpyrad in four major fruits using high-performance liquid chromatography (HPLC). All the confounds were extracted with acetone from apple, pear, grape, and citrus samples. The extract was diluted with saline water, and n-heaxane partition was followed to recover the acaricides. Florisil column chromatography was employed to further purify the sample extract. HPLC with ultraviolet absorption detection, using an octadecylsilyl column under the isocratic mobile phase of acetonitrile/water mixture, was successfully applied to separate and quantitate all the compounds in the purified extract. Recoveries of the eight acaricides from for fortified samples ranged 86.4~97.0%. Relative standard deviations of the analytical method were all less than 10%. Detection limits of the method were in the range of 0.02~0.05 mg/kg. The proposed method was reproducible and sensitive enough to evaluate the terminal residue of the eight acaricides in the fruit harvest.

• 한국환경보건학회지
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• 제9권1호
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• pp.89-93
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• 1983

Various analytical methods for p-Nitrophenol derivatives have been reported as follows. 1) Thin-Layer Chromatography, 2) Gas Chromatography, 3) Cholinesterase Activity Determination, 4) Diazo Method, 5) Nitrophenol Method, 6) Indophenol Method. But these methods are mainly analyse total quantity of p-Nitrophenol and are not available for the seperation and pose some analytical problems associated with extensive clean up procedure. A rapid and simple method was developed for the seperation and quantitation for the p-Nitrophenol and it's derivatives by HPLC. Also an experiment was undertaken by the authors for the quantitation of the p-Nitrophenol in the blood of the intoxicated body. Levels of p-Nitrophenol ranging from approximately 0.10 to $1.69 \mu g/ml$ for Parathion and $3.44 \mu g/ml$ for EPN in each sample were measured with the average recovery of $95.5\pm0.52%$

• 분석과학
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• 제16권1호
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• pp.78-81
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• 2003

Peptides separation in high performance liquid chromatography (HPLC) is very important for the analysis of total proteins using mass spectrometry rather than two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). In this study, we investigated the optimal HPLC condition of peptides for the use of mass fingerprinting. As a result of pursuing a combination of solvent additives for HPLC, water and acetonitile containing both 0.1% trifluoroacetic acid and 0.1% acetic acid respectively showed the most efficient resolution and sensitivity.

• 분석과학
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• 제17권1호
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• pp.85-89
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• 2004

라일락 꽃 향기 성분의 특성을 고체상 포집 용매추출법과 기체크로마토그래피 이온 포집형 질량분석법으로 연구하였다. 라일락 품종에 따라 향기성분의 조성이 현저한 차이를 보였다. 백색 라일락 꽃의 경우 벤즈알데히드, 페닐 아세트알데히드 및 알파-파네센인데 비하여 보라색 라일락 꽃은 벤즈알데히드, 알파-피넨 및 오시멘이 주된 향기성분으로 발견되었다. 라일락 꽃 향기성분 중 알파-피넨의 거울상 이성질체의 본질을 분석한 결과 ( )형태임을 알 수 있었다.

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.1-5
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• 1996

Rapid analytical method was investigated to determine precursors of N-nitrosamine such an nitrite and nitrate in squid(Illex illecebrosus and Sepiell maindroni), codfish(Gadus marcrocephalus)and flatfish(Paralichthys olivaceus) by ion chromatography(IC) and colorimetric methods. Recoveries of nitrite and nitrate in fish tissues were 89~98.7% and 94.1~99.8% for IC, and 98.4~103.7% and 67.7~102.2% for colori-metric method, respectively. Using IC, nitrite was not detected and nitrate was 0.89~1.23mg/kg, while using colorimetric method, nitrite and nitrate were NO~0.08mg/kg and 0.3~0.42mg/kg, respectively. Therefore, the IC method showed better recoveries, and was applicable to extract nitrite and nitrate simultaneously, and is simpler compared with colorimetric method in analyzing nitrite and nitrate from fish tissues.