• Analytical Science and Technology
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• v.7 no.2
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• pp.201-204
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• 1994

Cation exchange column chromatography of lithium was carried out to investigate the lithium isotope separation in aqueous ion exchange system. A Pyrex glass column of $50cm{\times}6mm$ inner radius with a water jacket was used as the separation column in experiment. Upon column chromatography using hydrochloric and succinic acid mixtures as an elunent, single separation factor, ${\alpha}$, 1.0068 was obtained. From the experiment, it was found that $^6Li$ was enriched in the resin phase and $^7Li$ in the solution phase.

• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.85-92
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• 2006

Crude oil is complex mixture if thousands of different organic compound formed from a variety of organic materials that are chemically converted under differing geological conditions over long periods of time. Also oil composition varies according to crude source, refining, processing, handling and storage. The oil fingerprint method is application if specific knowledge of petrochemicals and use if sophisticated analytical equipment and techniques to identify the source(s) if oil pollution. KCG currently utilizes four primary analytical techniques: Gas Chromatography (GC), Fluorescence Spectroscopy(FL), Infrared Spectroscopy(IR) and Gas Chromatography mass spectrometer(GC/MS). Of all these techniques, GC technique are most widely used Gas Chromatography is used as a primary analytical method because high reliableness, high separating efficiency and repeatability.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.3
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• pp.179-187
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• 2009

This paper describes the field evaluation of a sampling and analytical method for the quantity of airborne hexavalent chromium ($Cr^{6+}$) in the industrial areas, such as Sihwa and Banwol. Ambient measurements were performed by using the cellulose filter during the four seasons (October 2006 to June 2007). The determination of hexavalent chromium was carried out by ion chromatography. Performance validations, including method detection limit, relative standard deviation, and recovery percent, were also investigated. The mean concentrations of $Cr^{6+}$ in Sihwa and Banwol were 0.767 and 0.796 $ng/m^3$, respectively, which are similar to those of other foreign industrial areas. The seasonal variations of $Cr^{6+}$ levels were not quite different, which implies that the chromium was continuously emitted from the industrial sources throughout the year. The concentration variations between total chromium and $Cr^{6+}$ have also shown the similar pattern, suggesting that these components originate from the same sources. The concentration of $Cr^{6+}$ was found to be 0.7 to 2.4% of the total chromium. From these results, the approach using the cellulose filter may be suitable to collect $Cr^{6+}$ in the ambient air.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.85-85
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• 2003

한우 난소의 황체는 다양한 세포들로 구성되어 있으며 난소의 생식기능유지와 임신유지에 중요한 인자가 복잡하게 관련되어 있으며 이들 황체에서 분비하는 단백질은 황체기능에 필수적으로 중요한 작용을 한다. 본 연구는 난소의 황체일령에 따른 단백질 분비 패턴을 조사함으로써 황체세포의 기능과 임신 유지에 관련되는 인자들을 조사하기 위하여 수행하였다. 한우에서 채취한 난소에서 황체를 분리, 황체시기별(전기, 중기, 말기)로 구분하여 cytosol을 분리 정제하였다. 황체시기별로 분리된 황체 단백질의 성분을 분석하기 위해 ion-exchange chromatography를 이용하여 단백질 패턴을 조사, 추출된 fraction을 단백질 정량후 SDS-PAGE를 실시하였다. 그 결과 중기에서의 단백질의 농도가 가장 높았으며, 특히 단백질 패턴 또한 다른 양상을 보였다. 시기별로 구분한 각각의 fraction을 SDS-PAGE로 조사했을 때 중기와 말기황체 cytosol의 fraction 3번과 4번에서 다른 양상을 보였으며 SDS-PAGE에서 120kb, 95kb, 34kb, 25kb 등의 단백질 밴드를 확인할 수 있었다. 초, 중기황체에서만 특이하게 검출되는 단백질 band를 확인할 수 있었으며 이 들 단백질을 구체적으로 확인하기 위하여 Two-Dimensional electrophoresis를 이용하여 실험을 수행하였다. 시기별로 분리된 황체를 일반적인 IEF단백질 분리법으로 cytosol을 회수한 후 IPG-system을 이용하여 1차원 전기영동을 한 후, SDS-PAGE로 이차원 전기영동을 실시하였다. 이차원 전기영동 결과, SDS-PAGE의 결과와 비슷한 위치에 부분적으로 다른 spot의 양상을 보였다. 특히 기능황체에서의 특이적 발현 spot을 확인할 수 있었다. 이러한 결과들로부터 황체의 progesterone분비기능의 역할을 수행하기 위한 단백질들이 전, 중기에 발현된다는 것을 알 수 있고 퇴행황체에서는 발현이 안되고 있는 것을 알 수 있다. 이러한 결과를 토대로 다른 양상을 띤 spot을 분리하여 어떤 단백질인지를 분석하여 각각의 황체단백질의 특성을 규명할 수 있을 것으로 사료된다.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.103-110
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• 1986

Cytochrome P-450(CP-450) is one of the three components of the liver microsomal enzyme system which hydroxylates fatty acids, hydrocarbons and a variety of drugs and other foreign compounds. Female Balb/c mice were immunized with purified polychlorinated bipheny(PCB)-induced CP-450 LMII. The spleen cells derived from immunized mice were fused with $SP^2$ myeloma cells using polyethylene glycol(PEG 3500). The hybrid cells were selected by hypoxanthine-aminopterine and thymidine(HAT) medium and the culture fluid were screened by enzyme-linked immunosorbent assay to CP450 LMII. The hybrid cess(${\times}10^7$) were innoculated into intraperitoneal cavity of Balb/c mice for the purpose of production of ascitic fluids. Monoclonal antibody(Mab) was purified from ascitic fluid by DEAE cellulose ion exchange chromatography and $I^{125}$-labeled Mab was also confirmed by autoradiography and SDS-polyacrylamide gel electrophoresis (MW : 55,000 and 110,000).

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.211-215
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• 1988

Anion chromatographic (lC) method was developed for the determination of sulfites infoods. Sulfites refer to sulfur dioxide that was separated from a food sample by addition of acid and heating, and carried into a trapping solution by distillation. The trapping solution was applied to IC system. Sulfites was separated on an anionic separator column, HPIC-AS4A with 0.75mM $NAHCO_3/2.25mM\;Na_2CO_3$ as the eluent and determined by the use of conductivity detector. The recoveries of sulfites added to water, carrot and apple at level of 1 ppm were 99.8%, 91.6% and 83.5%, respectively. The detection limit was 0.2 ppm in the case of a 10 g sample size. All experiment could be finished within 20 minutes

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2039-2044
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• 2011

A semi-continuous and automated method for quantifying atmospheric ammonia at the parts per billion level has been developed. The instrument consists of a high efficiency diffusion scrubber, an electrolytic on-line anion exchange device, and a conductivity detector. Water soluble gases in sampled air diffuse through the porous membrane and are absorbed in an absorbing solution. Interferences are eliminated by using an anion exchange devises. The electrical conductivity of the solution is measured without chromatographic separation. The collection efficiency was over 99%. Over the 0-200 ppbv concentration range, the calibration was linear with $r^2$ = 0.99. The lower limit of detection was 0.09 ppbv. A parallel analysis of Seoul air over several days using this method and a diffusion scrubber coupled to an ion chromatography system showed acceptable agreement, $r^2$ = 0.940 (n = 686). This method can be applied for ambient air monitoring of ammonia.

• Journal of Veterinary Clinics
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• v.16 no.1
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• pp.31-36
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• 1999

The aim of this study is to determine the phagocytosis-promoting factor(s) for feline peripheral blood polymorphonuclear cells (PMN) by culture supernatant from mono-nuclear cells (MNC) treated with egg white derivatives (EWD). The phagocytic activity of PMN was analyzed by a flow cytometry system. The EWD did not show direct effect on the phagocytic response of PMN. The phagocytic activity of PMN was enhanced by culture supernatant from MNC but not PMN treated with EWD. Therefore, it was suggested that the enhanced phagocytic activity of feline PMN could be mediated by humoral factor(s) released from MNC treated with EWD. Thus, the phagocytosis-promoting factor(s) in supernatant fraction from MNC culture treated with EWD were isolated by reverse phase high pressure liquid chromatography. The resulting supernatant fraction on 29.02 minutes of retention time showed high phagocytic activity of PMN. The molecular weight of this supernatant fraction was 16 to 18 kDa when analyzed by capillary electrophoresis. The isoelectric point was pH 5.76 when assessed by ion-exchange chromatography. These results suggest that EWD stimulates feline MNC to elaborate a phagocytosis-promoting factor, 16 to 18 kDa of molecular weight, which could be an important mediator for the enhancement of phagocytic activity of feline peripheral blood phagocytes. Further study will be needed to elucidate this phagocytic factor.

• Analytical Science and Technology
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• v.32 no.3
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• pp.88-95
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• 2019

This study was conducted to establish the analytical method for the determination of cyanide in blood, urine, lung and skin tissues in rats. In order to detect or quantify the sodium cyanide in above biological matrixes, it was derivatized to Pentafluorobenzyl cyanide (PFB-CN) using pentafluorobenzyl bromide (PFB-Br) and then reaction substance was analyzed using gas chromatography mass spectrometer (GC/MS)-SIM (selected ion monitoring) mode. The analytical method for cyanide determination was validated with respect to parameters such as selectivity, system suitability, linearity, accuracy and precision. No interference peak was observed for the determination of cyanide in blank samples, zero samples and lower limit of quantification (LLOQ) samples. The lowest limit detection (LOD) for cyanide was $10{\mu}M$. The linear dynamic range was from 10 to $200{\mu}M$ for cyanide with correlation coefficients higher than 0.99. For quality control samples at four different concentrations including LLOQ that were analyzed in quintuplicate, on six separate occasions, the accuracy and precision range from -14.1 % to 14.5% and 2.7 % to 18.3 %, respectively. The GC/MS-based method of analysis established in this study could be applied to the toxicokinetic study of cyanide on biological matrix substrates such as blood, urine, lung and skin tissues.

• Archives of Pharmacal Research
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• v.28 no.10
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• pp.1190-1195
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• 2005

The objective of this study was to develop an assay for mequitazine (MQZ) for the study of the bioavailability of the drug in human subjects. Using one mL of human plasma, the pH of the sample was adjusted and MQZ in the aqueous phase extracted with hexane; the organic layer was then evaporated to dryness, reconstituted and an aliquot introduced to a gas chromatograph/mass spectrometer (GC/MS) system with ion-trap detector. Inter- and intra-day precision of the assay were less than 15.1 and $17.7{\%}$, respectively; Inter- and intra-day accuracy were less than 8.91 and $18.6{\%}$, respectively. The limit of quantification for the current assay was set at 1 ng/mL. To determine whether the current assay is applicable in a pharmacokinetic study for MQZ in human, oral formulation containing 10 mg MQZ was administered to healthy male subjects and blood samples collected. The current assay was able to quantify MQZ levels in most of the samples. The maximum concentration ($C_{max}$ was 8.5 ng/mL, which was obtained at 10.1 h, with mean half-life of approximately 45.5 h. Under the current sampling protocol, the ratio of $AUC_{t{\rightarrow}last}$ to $AUC_{t{\rightarrow}{\infty}}$ was $934{\%}$, indicating that the blood collection time of 216 h is reasonable for MQZ. Therefore, these observations indicate that an assay for MQZ in human plasma is developed by using GC/MS with ion-trap detector and validated for the study of pharmacokinetics of single oral dose of 10 mg MQZ, and that the current study design for the bioavailability study is adequate for the drug.