• Preventive Nutrition and Food Science
• /
• 제1권1호
• /
• pp.127-133
• /
• 1996

The development of high resolution capillary columns and a large variety of different detectors led to a strong position of gas chromatography in instrumental analysis. Every effort has been made to solve sophisticated separation problems by column switching. Nowadays, several systems are commercially available for this purpose. The principle and the capabilities of multidimensional gas chromatography(MDGC) are illustrated by different applications in the field of modern flavor and essential oil research.

• 한국식품과학회지
• /
• 제30권6호
• /
• pp.1247-1251
• /
• 1998

식초의 에탄올과 초산을 동시에 분석하고자 packed column으로 gas chromatographic analysis을 모색하였다. Tenax-GC를 충진물로 사용하여 $2\;m{\times}2\;mm$의 stainless steel column을 제조하고 식초를 여과하여 column에 직접 주입한 결과 내부 표준 물질로 사용한 isopropyl alcohol과 에탄올, 초산이 20분 이내에서 완전히 분리되었으며 정확도가 매우 높은 것으로(P<0.05)나타났다. 19종의 식초를 이용하여 적정방법으로 산도를, packed column GSC로 에탄올과 초산을, HPLC로 초산을, capillary column GLC로 에탄올과 초산을 각각 분석하여 분석치들을 상호 비교하였다.

• 약학회지
• /
• 제37권1호
• /
• pp.76-83
• /
• 1993

The changes in discharge current, emission and/or oscillation frequency of the electric oscillation of a glow discharge are the potential sensitive measure of the concentration of an impurity in the argon plasma supporting gas. A single jet enhanced glow discharge has been interfaced with the gas chromatograph via 1/8" O.D. tube with a heating pad to study the changes in discharge current. To investigate the optimum operating conditions of the glow discharge system as detector for gas chromatography, pressure, gas flow rate, discharge current, distance between the anode and the cathode have been studied.

• 약학회지
• /
• 제18권2호
• /
• pp.114-124
• /
• 1974

• 한국산업보건학회지
• /
• 제7권1호
• /
• pp.49-59
• /
• 1997

This study was performed to analyze the purity of technical grade ${\alpha}$-naphthylamine, to establish optimal analytical condition of ${\alpha}$-naphthylamine in urine and to determine the urine sample of workers exposed to ${\alpha}$-naphthylamine. The purity of technical grade ${\alpha}$-naphthylamine were $96.5{\pm}2.38%$, $94.1{\pm}0.97%$, $97.0{\pm}0.02%$ by gas chromatography-mass selective detector. To analyze ${\alpha}$-naphthylamine in urine, high performance liquid chromatography-electrochemical detector and gas chromatography-electron capture detector operating conditions have been optimized by preliminary expriment. In high performance liquid chromatography-electrochemical detector, the mobile phase was consisted of acetonitrile(35%) and water(65%), and the flow rate was maintained at 1.0ml per minute. Optimal detective condition was 9.0V(10nA/V) of electrochemical detector. The recovery of sep-pak treatment method was highly estimated as pretreatment of ${\alpha}$-naphthylamine in urine. The free amine was isolated by gas chromatography-electron capture detector after basic hydrosis, sep-pak treatment, toluene elution and HFBA(heptafluoro-butyric anhydride) derivatization of urine. The recovery of ${\alpha}$-naphthylamine in urine was $98.73{\pm}3.29%$ by gas chromatography-electron capture detector. The sensitivity was more higher than that of high performance liquid chromatography-electrochemical detector. Urinary ${\alpha}$-naphthylamine was detected in only one worker among nine workers. The level of ${\alpha}$-naphthylamine in urine was 6.42 ng/ml.

• Archives of Pharmacal Research
• /
• 제27권12호
• /
• pp.1295-1301
• /
• 2004

The enantiomeric composition tests on flurbiprofen and ketoprofen present in patch products and in urine excretions following patch applications were performed as diastereomeric (R)-(+)- 1-phenylethylamides by achiral gas chromatography and by gas chromatography-mass spectrometry in selected ion monitoring mode. The method for determination of (R)- and (S)-enantiomers in the range from 0.1 to 5.0 ${\mu}$g was linear (r ${\ge}$ 0.9996) with acceptable precision (% RSD ${\le}$5.2) and accuracy (% RE = 0.6 ~ -2.4). The enantiomeric compositions of flurbiprofen in one patch product and of ketoprofen in five different products were identified to be racemic with relatively good precision (${\le}$ 6.4%). The urinary excretion level of (R)-flurbiprofen was two times higher than its antipode, while the comparable excretion levels of (R)- and (S)-enantiomers for ketoprofen were observed.

• Mass Spectrometry Letters
• /
• 제12권4호
• /
• pp.186-191
• /
• 2021

A new method for chemical separation of light rare-earth elements (LREEs) using gas-pressurized extraction chromatography (GPEC) is described. GPEC is a microscale column chromatography system that features a constant flow of solvents, which is created by pressurized nitrogen gas. The separation column with a Teflon tubing was packed with LN resin. The proposed GPEC method facilitates production of lesser chemical wastes and faster separation owing to the use of low solvent volume compared to traditional column chromatography. We evaluated the separation of Ba, La, Ce, and Nd using various elution solvents. The column reproducibility of the proposed GPEC system ranged from 2.4% to 4.9% with RSDs of recoveries, and the column-to-column reproducibility ranged from 3.1% to 6.3% with RSDs of recoveries. The proposed technique is robust, and it can be useful for the fast separation of LREEs.

• 한국식품과학회지
• /
• 제25권4호
• /
• pp.299-306
• /
• 1993

본 연구에서는 일부 한국산 식품의 식이섬유 함량을 Englyst 등의 비색법과 gas chromatography 방법에 의한 비전분 다당류 분석에 의하여 측정하였다. Gas chromatography 방법에 의한 비전분다당류의 측정 결과, 곡류와 두류의 비전분다당류에서는 glucose와 5탄당인 arabinose 및 xylose, 미역, 다시마와 채소류의 불용성 비전분 다당류에서는 glucose, 수용성 비전분 다당류에는 uronic acid가 주요당이었다. 또한, 김의 불용성 및 수용성 비전분 다당류에는 galactose가 상당량 함유되어 있었다. Englyst와 Cummings의 비색법(x)과 gas chromatography 방법(y)에 의한 비전분다당류 값의 상관관계는 곡류, 두류 및 채소류의 식품군에서 y=1.01x-0.52(r=0.997, n=9)로 좋은 일치를 보여주었다. 한편 AOAC 공정법에 의한 총 식이섬유 함량(x)과 Englyst와 Cummings의 gas chromatography 방법에 의한 비전분 다당류 함량(y)의 상관관계 y=0.55x+2.14(r=0.786, n=12)로서 상관관계가 낮았으나, AOAC 공정법에 의한 총 식이섬유 함량(x)과 비전분 다당류 함량에 lignin 함량을 합한 값(y)의 상관관계는 y=0.68x+0.64(r=0.903, n=12)이었다.

• 한국환경보건학회지
• /
• 제5권1호
• /
• pp.58-60
• /
• 1978

This experiment was carried out to determine the amount of organophosphorous pesticides accumulated in farmer's blood during the farming season. The Blood had been collected for about 5ml from farmer's, and extraction was purified on a Avicel/Darco G-Co (1:10) column and determined by Gas Chromatography using AFID supported on 2% EGA. The Gas chromatographic detection yielded recoveries from the blood of 88% for smithion 94% for malathion. The amount of average contamination shows 0.045ppm for smithion. 0.054ppm for malathion.

• 약학회지
• /
• 제39권5호
• /
• pp.480-486
• /
• 1995

The change in discharge current of a glow discharge has been shown the potential sensitive detector for gas chromatography. To investigate the effect of carrier gas on the electrical characteristics of the discharge and the peak response, the discharge pressure, gas flow rate, and discharge gap have been studied. The discharge gas included the Ar, He, and N$_{2}$. The gas flow rate has been found one of the important parameters to affect both the electrical characteristics and the peak response.