• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.1-10
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• 1981

Volatile compounds in the headspace vapors of five aromatic tobacco varieties have been examined us ins the polymer adsorption method and high- resolution glass capillary gas chromatography. The gas chromatographic profiles thus obtained were compared, and the aroma composition was found to be characteristic of each tobacco sample with significant differences in the concentrations of major components.

• Journal of the Korean Chemical Society
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• v.39 no.5
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• pp.414-420
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• 1995

$\alpha$-Bromo-$\omega$-fluoroalkanes are synthesized in 19∼55% yields from the reactions of dibromoalkanes with AgF and TBABr in acetonitrile at $82^{\circ}C$ for 20 minutes. The reaction is monitored with gas-chromatography. 1^H$ NMR and $19^F$ NMR-Spectrometer are used for identification of $\alpha$-Bromo-$\omega$-fluoroalkanes, difluoroalkane, fluoroalken and bromoalkene.

• Journal of the Korean Chemical Society
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• v.28 no.4
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• pp.244-250
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• 1984

Separation and identification of the polycyclic aromatic compounds (PAC) from pyrolysis products of cellulose and lignin were performed using a combination of acid-base solvent partitioning and silicic acid column chromatography with fused-silica capillary column gas chromatography/ mass spectrometry. Sixteen PAC were positively identifited by retention indices and mass spectra data. Both materials produced the same kinds of PAC. But lignin produced much more PAC than cellulose. Almost no highly carcinogenic heterocyclic PAC containing nitrogen and sulfur were produced.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.269-272
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• 1989

In order to obtain monoclonal antibody from ascites fluid at sufficiently high purity using a single hydroxylapatite chromatography (HA) a further optimization on its operating variables was carried out. By adjusting the pH of the eluent, the sodium phosphate buffer, to 6.0 from 6.8 and adding CaCl$_2$to 1 mM at the column inlet, the elution molarities (M$_{elu}$) for the desired monoclonal antibody and contaminating proteins can be distinguished from each other with enough resolution. Previously these two groups of proteins co-eluted at the same time at pH 6.8 and without CaCl$_2$. This sin81e step hydroxylapatite chromatography yields the desired antibody pure enough for diagnostic use.

• The Korean Journal of Zoology
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• v.29 no.4
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• pp.283-293
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• 1986

For the preliminary step to make and characterize the monoclonal antibodies of human alpha-fetoprotein (AFP) was purified from 534g of human fetal tissues through the procedures of tissue extraction, DEAE-cellulose, concanavalin A-Sepharose, Cibacron Blue F3GA-agarose and immunoadsorbent affinity chromatography. The isolated AFP preparation showed a single band on polyacrylamide gel electrophoresis and a single precipitin are against rabbit anti-human cord serum and anti-human AFP on immunoelectrophoresis. Our AFP also displayed a single band on SDS-polyacrylamide gel electrophoresis. The recovery of AFP was 8.76mg total.

• Korean Journal of Pharmacognosy
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• v.4 no.2
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• pp.59-61
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• 1973

• Proceedings of the Korean Society of Veterinary Service Conference
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• 1994.04a
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• pp.140.4-141
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• 1994

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.21-25
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• 2001

Major saponins in ginseng were analysed using reverse phase high performance liquid chromatography with binary mobile phase gradient control system instead of normal phase column. The optimum condition were as following : reverse phase column; ${\mu}{\beta}ondapak\;C_{18}$ column (Waters, $3.9mm{\times}300\;mm,\;5{\mu}m$), methyl cyanaide/water binary mobile phase gradient control system, solvent flow rate; 1.5 ml/min, and UV($203{\mu}m$ ) detector. The complete separation of ginsenoside $Rb_1,\;Rb_2,\;Rc,\;Rd,\;Re,\;Rf\;and\;Rg_1$ was achieved within 55 min. The Regression coefficients of the calibration curves for seven ginsenosides were 0.99.

• Journal of Life Science
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• v.19 no.12
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• pp.1698-1704
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• 2009

Gemcitabine is an anticancer drug used to treat a variety of solid tumors. The drug is rapidly inactivated by cytidine deaminase in plasma and its hydrophilicity restricts the extent of quantification that is possible using reversed-phase liquid chromatography. In this paper, we report a rapid and precise method to analyze velocity and peak efficiency using ultra-performance liquid chromatography (UPLC) with a reversed-phase column. The retention periods of gemcitabine and 2'-deoxycytidine at 283 nm were 3.2 and 2.1 min, respectively. The assay provided highly linear results in the range of $0.1{\sim}20{\mu}g/ml$ ($r^2$ > 0.999). The coefficients of variation of the intra-day and inter-day assays were less than 10.0%. We observed that the estimated average concentrations of the intra-day and inter-day assays ranged from 97.3 to 113.5% to verify the accuracy. These results suggest that this new reversed-phase UPLC method is a rapid and reliable way of determining gemcitabine levels.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.154-161
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• 1991

An objective method for measuring rancidity in soybean oil was developed based on the volatile contents obtained by headspace gas chromatographic analysis. Apparatus for headspace volatile cold trapping-thermal desorption was described, designed to collect and analyze volatiles of soybean oil. Samples of commercially processed soybean oil were stored under controlled condition and then evaluated for flavor by a eight member trained panel and for volatile contents by headspace gas chromatographic analysis. Twenty-three GC peaks were identified on the basis of relative retention time of reference compounds and gas chromatography-mass spectrometry. The volatile compounds identified were autoxidation products of principal unsaturated fatty acids of soybean oil. The simple linear regressions of flavor score with the pentanal or hexanal contents in aged soybean oil gave correlation coefficient of 0.990 and 0.994. respectively. Pentanal and hexanal contents could be used as a potentially useful index for predicting flavor scores of soybean oil.