• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.406.3-407
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• 2002

Analysis of interferon alpha (IFN) modified with high molecular weight branched PEG was performed by capillary electrophoresis (CE) and MALDI-TOF mass spectrometry (MALDI-TOF MS). IFN was modified by the reaction of amine residues with an active ester of monomethoxy polyethylene glycol at various molar ratios. As a CE method. capilary electrophoresis sodium dodecyl sulfate nongel sieving (CE-SDS NGS) was performed using an uncoated capilary filled with a hydrophilic replaceable polymer network matrix. (omitted)

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권11호
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• pp.640-648
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• 2000

We have developed a synchronously switched cyclic capillary electrophoresis (CE) separator that is fabricated on a silicon substrate and glass containing reservoirs, Au electrode, and isolated channels. The advantage of a cyclic separator is the high resolution and ability to separate each sample to the designated reservoir from mixed samples. This approach makes it possible to reduce the supplied voltage and the total size. Another goal of this work is to introduce the methodolgy of electroosmosis flow(EOF) to silicon substrate and to separate DNA samples using a modified double-T injector.

• Plant Resources
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• 제6권1호
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• pp.81-88
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• 2003

Higenamine [1-(4-hydroxy-6, 7-dihydroxy-l, 2, 3, 4-tetrahydroisoquinoline) is a cardiotonic constituent of Aconiti tuber, one of the most widely prescribed oriental medicines. S-(-)higenamine was reported to have a stronger cardiotonic activity than R-(+)-higenamine and known as a central intermediate in the biosynthesis of various benzyl isoquionoline alkaloids in plants. The separation of higenamine enantiomers has been accomplished with capillary electrophoresis using cyclodextrins (CDs) as chiral selectors. Good resolution of this enantiomers was obtained using a 50 mM sodium phosphate buffer containing hydroxypropyl $\beta$-CDs using 27 cm fused silica capillary (50${\mu}{\textrm}{m}$ i.d., 20 cm to detector) at 25 $^{\circ}C$. With the electric field of 340 V/cm, the separation time of higenamine enantiomers was less than 6 min. Under this optimum conditions, the relative standard deviations of migration time and peak area were less than 1.6% and 3.2%. A 512-channel diode array detector was confirmed for the higenamine. The detection limits (S/N = 3) of these enantiomers are $1.5mutextrm{m}$/mL. We confirmed the chiral form of higenamine in medicinal plants.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.400.1-400.1
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• 2002

Because of the differences in pharmacological properties between enantiomers of chiral acidic non-steroidal antiinflammatory drugs (NSAIDs) in human body. accurate determinations of their optical purities have been in great need. An efficient capillary electrophoretic (CE) profiling method was developed for the enantioseparation of NSAIDs. Capillary electrophoretic conditions were optimized using TM$\beta$-cyclodextrin as the chiral selectors under MES buffer. (omitted)

• 한국식품과학회지
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• 제34권5호
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• pp.787-791
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• 2002

수입자유화이후 유입량이 급증한 농산물중 하나인 율무의 원산지 판별을 위하여 CE의 적용가능성을 검토하였다. 분석을 위한 지표물질의 추출을 위해 30% ethanol을 사용하였으며, $50\;{\mu}m\;I.D.{\times}27\;cm$(20 cm inlet to detector)의 capillary를 이용하여 $45^{\circ}C$, 15 kV로 200 nm에서 detect 하였다. 분석 buffer는 0.1 M phosphate buffer(pH 2.5)에 30% methanol과 26 mM HSA를 첨가하였으며, pressure injection 20초, detector rise time 0.1초로 하였다. 분석시 초기에 증류수와 0.1 M phosphate buffer(pH 2.5)로 각 5분씩 capillary를 rinse하고 분석 buffer로 10분간 equilibration 시킨 후 30분간 분석하고 다시 1 M phosphoric acid로 14분간 rinse하여 다음 시료 분석시의 오차를 줄였다. 이 조건으로 2000년 및 2001년의 국산 및 수입산 율무 총 240점을 분석한 결과 서로를 구분하는 peak JT5의 도출이 가능하였으며 이 peak JT5에 의한 국산 및 수입산 율무의 판별율은 2000년 시료에서는 국산이 총 47점 중 39점(판별율 약 83%), 수입산은 총 48점 중 39점(판별율 약 81%), 2001년 시료는 국산 총 74점 중 60점(판별율 약 81%), 수입산은 총 71점 중 59점(판별율 약 83%)이었으며 전체적으로 약 82%의 판별율을 나타내었다.

• 대한화학회지
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• 제48권2호
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• pp.144-150
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• 2004

모세관 전기영동을 이용한 박테리아의 분석에 영향을 주는 다양한 실험적인 요인을 연구하였다. 여러 완충액 농도에서 gram-positive 박테리아에 비해 gram-negative 박테리아는 높은 전기장 하에서 다른 분리 거동을 보임을 확인하였다. 한편, 모세관 내부로 주입되는 박테리아의 농도에 따른 분리 효율의 차이가 연구되었다. 완충액에 존재하는 박테리아 시료의 농도가 비교적 높은 1.0 mg/ml일때 좋은 분리 효율이 얻어졌으며, 이것은 박테리아의 높은 농도에서 발생하는 focusing effect에 의한 결과로 보인다. 선형 고분자인 poly(ethylene)oxide(PEO), polyvinylpyirrolidone(PVP)와 가지형 고분자인 dextran을 크기와 형태적 차이로서 박테리아를 분리하기 위하여 테스트하였다. 다른 고분자와 달리 보다 유연하며 입체 장애가 적은 선형 고분자인 PEO를 포함하는 완충액에서 gram-positve 박테리아인 Micrococcus lysodeikticus와 gram-negative 박테리아인 Aerobacter aerogenes의 혼합물을 높은 효율로 분리하였다.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1496-1500
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• 2010

Sibutramine enantiomers were separated successfully by capillary zone electrophoresis using substituted cyclodextrins as chiral selectors. The effects of cyclodextrin concentration, pH, voltage, buffer type, and electrolyte concentration on the migration time and resolution of enantiomers were examined. Separation of sibutramine enantiomers on an unmodified fused silica capillary (total length, 54 cm; effective length, 45 cm) was achieved using a mixed buffer of 20 mM phosphate/10 mM citrate containing either 5 mM methyl-${\beta}$-cyclodextrin (pH 4.3) or 5 mM carboxymethyl-${\beta}$-cyclodextrin (pH 6.5). Samples were injected with a pressure of 50 mbar for 5 s and were detected at a wavelength of 223 nm. The established method showed good precision and accuracy, with intra- and inter-day variations of less than 2.9 and 4.7%, respectively, and recoveries of 95.7 - 103.8%. The stability constants of (R)- and (S)-sibutramine demonstrated that the resolution of sibutramine enantiomers was attributable primarily to the difference in stability constants. When this optimized method was applied to the determination of sibutramine enantiomers in commercial drug formulations, it proved to be economical and convenient, affording sufficient accuracy, precision, and reproducibility as well as sensitivity and selectivity.

• 분석과학
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• 제32권5호
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• pp.185-195
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• 2019

Over the past decades, chiral switch of the proton pump inhibitors (PPIs) has been received widespread attention in therapeutic advantages as well as pharmaceutical analysis. In present study, the influence of cyclodextrins (CDs) on the chiral separation of four common PPIs (lansoprazole, omeprazole, pantoprazole, and rabeprazole) was investigated. The results demonstrated that capillary electrophoresis (CE) with dual CDs as a chiral selector system is a possible and promising method for the enantioseparation of these PPIs. Rabeprazole, which is the most challenging and acid-labile candidate among four PPIs, was selected for further development of the technique. To optimize CE condition, the effects of capillary parameters and background electrolytes on the enantioseparation were investigated. Finally, the best chiral separation was acheived by using sulfobutyl ether-${\beta}$-CD, and ${\gamma}$-CD as dual chiral selectors. The developed CE method not only provided the effective chiral separation but also showed the good stability of rabeprazole. The proposed method was successfully validated according to the International Conference on Harmonization guideline and effectively applied to determine rabeprazole enantiomers in commercial rabeprazole tablets, with recoveries ranging from 97.17 % to 103.29 % of the label content.

• 환경위생공학
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• 제13권1호
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• pp.195-202
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• 1998

• 식품기술
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• 제7권2호
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• pp.74-80
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• 1994