• 대한화학회지
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• 제7권2호
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• pp.128-132
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• 1963

A study has been made on the applicability of gas-liquid partition chromatography to the qualitative and quantitative analysis of complex mixture of gaseous hydrocarbons. While phthalate columns are widely used for this $purpose^9$, they separates neither saturated hydrocarbons from the unsaturated nor n-butane from isobutene or butene-1, therefore combined columns such as phthalate and dimethylsulfolane have been used for the perfect separation of gaseous hydrocarbons. It is shown by this study, however, that hydrocarbons having $C_1$ through $C_4$ can be separated with a 2-meters tetraethyleneglycol dimethylether column except ethane from ethylene, and trans-from cis-2-butene especially operated at $15^{\circ}C$$ using helium as the carrier gas. The column effluents were in order of methane, (ethane, ethylene), propane, propylene, isobutane, n-butane, isobutylene, butene-1, (trans-& cis-2-butene, isopentane), (butadiene-1, 3, n-pentane). Two kinds of liquified petroleum gases in market are analysed qualitatively and quantitatively. The results indicate that use of this 2-meters TEGDE column permits the separation and identification of all the commonly encountered aliphatic gaseous hydrocarbons.

• BMB Reports
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• 제40권5호
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• pp.801-804
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• 2007

The products of reactions catalyzed by Methanococcus. jannaschii (Mj) aldolase using various substrates were identified by gas chromatography (GC). Although Mj aldolase is considered a fuculose-1-phosphate aldolase based on homology searching after gene sequencing, it has not been proven to be a fuculose-1-phosphate aldolase based on its reaction products. Mj aldolase was found to catalyze reactions between glycoaldehyde or D, L-glyceraldehyde and DHAP (dihydroxyacetone phosphate). Before performing GC the ketoses produced were converted into peracetylated alditol derivatives by sequential reactions, i.e., dephosphorylation, $NaBH_4$ reduction, and acetylation. By comparing the GC data of final products with those of standard alditol samples, it was found that the enzymatic reactions with glycoaldehyde, D-glyceraldehyde, and D, L-glyceraldehyde produced D-ribulose-1-phosphate, D-psicose-1-phosphate, and a mixture of D-psicose and L-tagatose-1-phosphate, respectively. These results provide direct evidence that Mj aldolase is a fuculose-1-phosphate aldolase.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2691-2696
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• 2013

The electronic cigarette (E-cigarette) is a battery-powered device that aerosolizes nicotine so that it is readily delivered into the respiratory tract. The analytical data regarding the substances present in E-cigarettes are very limited. The aim of this study was to measure the concentration of aldehydes-formaldehyde (FA), acetaldehyde (AA) and, acrolein (AL)-in 225 replacement liquid brands from 17 E-cigarette shops sold in the Republic of Korea by headspace solid-phase micro extraction and gas chromatography-mass spectrometry (HS-SPME GC-MS). The concentration range of FA and AA was 0.02-10.09 mg/L (mean = 2.16 mg/L, detected in 207 of 225 samples) and 0.10-15.63 mg/L (mean = 4.98 mg/L, detected in all samples), respectively. AL was not detected in any of 225 replacement liquids. FA and AA were originally present in almost all replacement liquids of electronic cigarettes.

• Mass Spectrometry Letters
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• 제3권2호
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• pp.29-38
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• 2012

A new approach of volatile compounds analysis is proposed using a linear ion trap Orbitrap mass spectrometer coupled with gas chromatography through an atmospheric pressure photoionization interface. In the proposed GC-HRMS/MS approach, direct chemical composition analysis is made for the precursor ions in high resolution MS spectra and the structural identifications were made through the database search of high quality MS/MS spectra. Successful analysis of a complex perfume sample was demonstrated and compared with GC-EI-Q and GC-EI-TOF. The current approach is complementary to conventional GC-EI-MS analysis and can identify low abundance co-eluting compounds. Toluene co-sprayed as a dopant through API probe significantly enhanced ionization of certain compounds and reduced oxidation during the ionization.

• 한국해양학회지
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• 제20권1호
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• pp.74-82
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• 1985

海洋에 기름이 流出되면 蒸發, 溶解, 酸化 및 미생물 分解等의 영향을 받는다. 그러므로 GC에 의한 탄화수소와 黃化合物을 分析하기 위하여 人工的으로 經時變化 시키면서 시료을 채취하였다. GC분석결과 시료유는 저마다의 독특한 형태의 Chromatogram을 나타내고 있다. 탄화수소 중의 低비점 성분의 Peak는 시간이 경과하면서 감소하고 있다. 그러나 FPD에 의해 黃化合物을 分析한 Chromatogram 은 비교적 經時變化의 영향을 적게 받고있다. GC에 의한 탄화수소 및 黃化合物 分析法은 流出油를 비교 分析하여 汚染源을 識別하는데 重要한 方法이다.

• Archives of Pharmacal Research
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• 제27권8호
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• pp.820-824
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• 2004

An optical purity test was indirectly performed on (S)-ibuprofen as its diastereomeric (R)-(+)-1-phenylethylamide derivative using achiral gas chromatography (GC). The method for the determination of trace (R)-ibuprofen (optical impurity), within the range 1.0 to 50 ng, from a racemic ibuprofen standard was linear (r＝0.9997) with acceptable precision (％ $RSD{\leq}5.3$) and accuracy (％ RE＝0.7~-3.9). Similar results were obtained with the method validation for the quantification of (S)-ibuprofen within the range 0.1 to 2.0 $\mu\textrm{g}$ using a (S)-ibuprofen stan-dard. When applied to seven different commercial (S)-ibuprofen products, their optical purities (98.7~99.1％) were determined with good precision (％ $RSD{\leq}4.0$).

• 생약학회지
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• 제4권2호
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• pp.71-74
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• 1973

The contents of volatile oil and camphor in the oil of Artemisia messer-schmidtiana $B_{ESSER}$ var. viridis $B_{ESSER}$ f. typica $N_{AKAI}$ and Artemisia asiatica $N_{AKAI}$ which were known to be effective as antibacterial, antifungal and antineoplastic agents by screening experimentation, were determined quantatively by gas chromatography. The volatile oil contents of Artemisia messer-schmidtiana $B_{ESSER}$ var. viridis $B_{ESSER}$ f. typica $N_{AKAI}$ and Artemisia asiatica $N_{AKAI}$ are 0.17% and 0.19%, and the camphor contents are 8.51% and 1.46%, respectively.

• Natural Product Sciences
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• 제10권1호
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• pp.29-31
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• 2004

A new method for the quantitative determination of fucosterol in the marine algae Pelvetia siliquosa by gas chromatography was established. A HP-1 column programmed as $200^{\circ}C\;(5\;min)\;{\rightarrow}\;5/min\;{\rightarrow}\;280^{\circ}C\;(10\;min)$ was developed. The analysis of fucosterol in P. siliquosa was successfully carried out within 30 min.

• Natural Product Sciences
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• 제16권3호
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• pp.180-184
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• 2010

The simple and accurate method was established for the simultaneous determination of (-)-menthone and (-)-menthol in Menthae herba obtained from Korea and China. A quantitative analysis was performed with a gas chromatography-flame ionization detector and reference compounds were separated on a capillary HP-Innowax column (30 m $\times$ 0.23 mm, 0.50 ${\mu}m$, Agilent, MA, USA). The correlation coefficients of the compounds showed good linearity ($r^2$ > 0.9997) over the linear range. The precision, repeatability and stability showed less than 1.7% of relative standard deviation (RSD) values for two compounds. Recovery rates were within the range of 95.72 - 103.76%. The method was applied successfully to analyze 15 samples of Menthae herba and achieved sufficient and specific separation of reference compounds. The principal component analysis (PCA) exhibited the classification of 15 samples according to their locations of origin.

• Food Science and Biotechnology
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• 제18권2호
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• pp.379-383
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• 2009

For an accurate risk assessment of furan, a potential human carcinogen, levels must be determined in human blood plasma using a simple and robust assay. In this study, solid phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) was used to analyze blood plasma levels of furan in 100 healthy individuals who consumed a normal diet. The subjects were 30 to 70 years of age and 51% were women. Ultimately, an analytical method was established for analyzing furan in human blood. The limit of quantification (LOQ) and furan recovery rate in blood were 1.0 ppb and 104%, respectively. Finally, furan was detected in 21 individuals (13 males, 8 females) with levels ranging up to 17.86 ppb (ng furan/g food).