• 대한기계학회논문집
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• 제9권6호
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• pp.743-749
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• 1985

본 연구에서는 Gas Chromatograph를 사용하여 1,500㏄급 국산 소형 승용차 엔 진의 배기가스 성분을 분석하였다. 그리고 이를 통하여 배개가스 성분 분석에 Gas Chromatograph를 사용할 경우 아래와 같은 점에 유의한다면 배기가스 성분을 비교적 정확하게 측정할 수 있다는 것을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.539-545
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• 2014

Styrene-acrylamide co-polymer was immobilized on porous partially sub-$2{\mu}m$ silica monolith particles and inner surface of fused silica capillary ($50{\mu}m$ ID and 28 cm length) to result in ${\mu}LC$ and CEC stationary phases, respectively, for separation of anomeric D-glucose derivatives. Reversed addition-fragmentation transfer (RAFT) polymerization was incorporated to induce surface polymerization. Acrylamide was employed to incorporate amide-functionality in the stationary phase. The resultant ${\mu}LC$ and CEC stationary phases were able to separate isomers of D-glucose derivatives with high selectivity and efficiency. The mobile phase of 75/25 (v/v) acetonitrile (ACN)/water with 0.1% TFA, was used for HPLC with a packed column (1 mm ID, 300 mm length). The effects of pH and ACN composition on anomeric separation of D-glucose in CEC have been examined. A mobile phase of 85/15 (v/v) ACN/30 mM sodium acetate pH 6.7 was found the optimized mobile phase for CEC. The CEC stationary phase also gave good separation of other saccharides such as maltotriose and Dextran 1500 (MW~1500) with good separation efficiency (number of theoretical plates ~300,000/m).

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.601-606
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• 2007

The chromatographic behaviors of nucleotides (inosine 5'-monophosphate, uridine 5'-monophosphate, guanosine 5'-monophosphate, and thymine monophosphate disodium salts) on a C18 column were studied with different types of ionic liquids (ILs) as additives for the mobile phase in reversed-phase liquid chromatography (RPLC). Three ILs, 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF4]), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIm][BF4]), and 1-ethyl-3-methylimidazolium methylsulfate ([EMIm][MS]), were used. Eluents were composed of water and methanol (90/10%, vol) with the addition of 0.5-13.0 mM of ILs. The effects of the concentration of ILs on retention and separation were investigated and discussed. The results showed that the addition of ILs affects the retention and resolution of the tested compounds. Use of 13.0 mM of [BMIm][BF4] as the eluent modifier resulted in a baseline separation of nucleotides without requiring gradient elution. This study demonstrates that ILs can be potentially applied as a mobile phase modifier in RPLC.

• Bulletin of the Korean Chemical Society
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• 제11권5호
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• pp.411-415
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• 1990

The dabsylation of amino acids has been applied to resolve their optical isomers with the use of chiral mobile phase in high performance liquid chromatography. The dabsyl amino acids were successfully separated on reversed phase column($C_{18}$) by adding a chiral L-benzylproline-Cu(II) chelate to the mobile phase. The separation selectivity of the dabsyl amino acid enantiomers was not less than that of dansyl amino acids. The retention order of the dabsyl amino acid enantiomers was as those of the dansyl amino acid enantiomers except dabsyl threonine. The optical selectivity of the dabsyl amino acids increase with pH of the mobile phase and concentration of the chelate, but slightly decreases with concentration of buffer and organic solvent composition. However serine, methionine, valine, and leucine showed a slight decrease in the optical selectivity with increase in pH. The retention times of the dabsyl amino acids decreases with increasing pH and acetonitrile concentration but increases with the concentration of the chiral chelate added. The mechanism of the optical resolution is based on a stereospecific interaction including a intramolecular hydrophobic effect and SN-2 reactivity of the ligand exchange chromatography.It is advantageous to detect absorption at 436 nm, which is less interferent them the other detection systems. The derivatized dabsyl amino acids are stable for a month.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.633-634
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• 2001

Porcine pancrease lipase를 aldehyde-silica에 in situ 상태에서 immobilization 할때의 최적 조건에 대하여 연구하였다. Feed 용액의 조성비율, 양, pH, 온도, 농도, 유속에 대하여 최적화하였으며 lipase의 activity를 측정 비교하였다.

• Journal of Pharmaceutical Investigation
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• 제37권3호
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• pp.187-192
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• 2007

A reversed phase HPLC analysis of atorvastatin (AS) standard solution was performed using diclofenac (DF) as internal standard. Column oven temperature, flow rate and the composition of the mobile phase were varied in order to determine a practical system setup using a C18 column and UV detector. Two C18 columns of different length were compared regarding their influence on the AS peak shape. Based on these preliminary experiments a validation study was performed utilizing a C18 column at $62^{\circ}C$ with a mobile phase consisting of sodium phosphate buffer (0.05 M, pH 4.0), methanol and acetonitrile (40:50:10, v/v/v). The detection limit for AS was $0.1{\mu}g/ml$ and inter- and intra-day calibration curves were linear over a concentration range of $0.2-50{\mu}g/ml$. Accuracy and precision were satisfactory in the AS concentration range of $0.5-50{\mu}g/ml$.

• 공업화학
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• 제8권2호
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• pp.315-319
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• 1997

본 연구는 역상 액체 크로마토그래피를 이용하여 비이온 계면활성제의 propylene oxide 분포 및 고급 지방 알콜의 최적 분석 조건을 조사하였다. Propylene oxide 분포 및 지방 알콜의 탄소 길이를 분석하기 위해 UV 검출기를 사용할 수 있도록 유도체화 시켰으며 최적 분리 조건을 얻기 위해 분리관의 영향과 이동상의 조성 등을 실험하였다. 분리관은 Waters Symmetry $C_8(3.9{\times}150mm)$을 사용하였고 이동상은 methanol과 물을 이용한 기울기 용리에 의한 분석이 최적 조건이었다. 그리고 이들의 용리 거동은 log k'와 물의 부피 분율을 도시한 결과 좋은 직선성을 얻었고 고급 알콜의 정량성을 알아보기 위하여 검량선을 도시한 결과 직선성이 좋은 결과를 얻었다.

• Journal of Pharmaceutical Investigation
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• 제22권4호
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• pp.317-321
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• 1992

A high-performance liquid chromatographic (HPLC) method was developed for the determination of diltiazem (DTZ) and its major metabolite, deacetyldiltiazem (DAD), in rat plasma. DTZ, DAD and imipramine, the internal standard, were selectively fractionated from plasma on a $C_{18}$ reversedphase column $({\mu}-Bondapak,\;10\;{\mu}m\;silica,\;300{\times}3.9\;mm\;ID)$. The composition of the mobile phase was methanol: acetonitrile: 0.04 M ammonium bromide: triethylamine (40:24:36:0.06 in volume). The pH of the mobile phase of their method was lowered to 6.4. The eluents from the column were detected for DTZ and DAD using a UV detector at 237 nm. The recovery was >85% for DTZ and DAD, and average intra-day and inter-day coefficients of variation were <6% for DTZ and DAD at the concentration ranges of 20-1000 ng/ml. Detection limit of DTZ and DAD in plasma was 20 ng/ml with signal-to-noise ratio of 3. This method would be applicable to practical pharmacokinetic studies without detriment to the HPLC column.

• 공업화학
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• 제8권2호
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• pp.286-291
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• 1997

항암제로 탁월한 효능이 있는 taxol을 정상 액체 크로마토그래피를 이용하여 주목나무의 추출물에서 분리하였다. Taxol을 분리하기 위해 시료 주입량은 $5{\mu}l$에서 $100{\mu}l$로 변화시키고, 이동상 유속은 1ml/min로 고정하여 일정 용매법으로 실험을 하였다. 실험에 사용된 이동상은 헥산, 에탄올, 메탄올, 1-프로판올, 이소프로판올이었다. Taxol과 유사한 성질를 갖는 표준시료 cephalomannine, taxol, 10-deacetyltaxol의 혼합물에서 taxol을 분리하였다. Cephalomannine, taxol, 10-deacetyltaxol 혼합물의 분리 실험 결과로 taxol의 분리 최적 조건은 2성분계에서 헥산/에탄올의 부피 조성비가 96/4이며, 3성분계에서는 헥산/1-프로판올/메탄올의 부피 조성비가 96/2/2이었다. 분리시간은 2성분계에서 80분인데 비해 3성분계에서는 50분으로 적은 용매를 사용하여 분리할 수 있었다. 위에서 얻는 실험조건으로 실제 주목나무의 추출물 $1{\mu}g$에서 taxol를 분리할 수 있었다.

• 공업화학
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• 제7권5호
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• pp.985-991
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• 1996

HETP(Height Equivalent to a Theoretical Plate)는 크로마토그래피 공정에서 관의 효율을 나타내는 정량적 인자이다. 본 연구에서는 시료의 농도와 주입량, 이동상의 유속과 조성이 제조용 액체 크로마토그래피의 HETP에 미치는 영향을 고찰하였다. 시료는 thymidine이고 이동상은 1.5~5.5ml/min의 유속에서 일정용매조성법으로 물과 organic modifier로서 메탄올을 사용하였으며 제조용 크로마토그래피 column은 길이가 500mm, 내경이 9.8mm이다. 시료의 농도와 주입부피 및 유속이 증가함에 따라 HETP는 거의 선형적으로 증가하여 관의 효율이 감소하였다. 시료 주입부피의 영향은 관의 효율에 매우 중요하게 작용하여 동일한 주입량에 대하여 주입부피가 10배로 증가함에 따라 HETP는 약 2배 정도로 커졌다. 이동상의 유속이 증가함에 따라서 HETP는 주로 이동상과 고정상의 물질전달저항에 의해서 증가하였다.