• Archives of Pharmacal Research
• /
• 제27권9호
• /
• pp.973-977
• /
• 2004

Carvedilol is administered as a racemic mixture of the R(＋)- and S(-)-enantiomers, although they exhibit different pharmacological effects. To investigate the stereoselective pharmacoki-netics, the enantiomeric separation of carvedilol in human plasma was undertaken using capil-lary electrophoresis (CE). Resolution of the enantiomers was achieved using 2-hydoxypropyl-$\beta$-cyclodextrin as the chiral selector. Phosphate buffer (50 mM, pH 4.0) containing 10 mM of 2-hydoxypropropyl-$\beta$-cyclodextrin was used as electrolytic buffer. Achiral separation was carried out with the same electrolytic buffer without chiral selector. Following a single oral administra-tion of 25-mg carvedilol to 11 healthy, male volunteers, stereoselective pharmacokinetic analy-sis was undertaken. The maximum plasma concentrations ( $C_{max}$) were 48.9 and 21.6 ng/mL for (R)-carvedilol and (S)-carvedilol, respectively, determined by the chiral method. The profiles of the plasma concentration of (RS)-carvedilol showed $C_{max}$ of 71.5, 72.2, and 73.5 ng/mL, as determined by the CE, HPLC/FD methods and calculations from the data of the chiral method, respectively.y.y.

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

• KSBB Journal
• /
• 제27권4호
• /
• pp.199-206
• /
• 2012

Chiral crown ethers are synthetic macrocyclic polyethers that bind protonated chiral primary amines with high selectivity and affinity. They have been widely used to separate or distinguish the enantiomers of chiral compounds containing a primary amino moiety by high-performance liquid chromatography, capillary electrophoresis, and NMR spectroscopy. In this paper, two important chiral crown ethers including chiral binaphthyl unit and (18-crown-6)-2,3,11,12-tetracarboxylic acid as chiral selectors are focused. And several chiral resolution techniques and their applications in chirotechnology using these chiral crown ethers with related chiral recognition mechanism studies are reviewed. Especially, it was shown that the commercially available HPLC columns based on (18-crown-6)-2,3,11,12-tetracarboxylic acid have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• Archives of Pharmacal Research
• /
• 제26권2호
• /
• pp.120-123
• /
• 2003

A method for the determination of terbutaline enantiomers in human urine by capillary elctrophoresis has been developed. Optimum resolution was achieved using 50 mM phosphate buffer, pH 2.5, containing 15 mM of hydroxypropyl-$\beta$-cyclodextrin as a chiral selector. Urine samples were prepared by solid-phase extraction with Sep-pak silica, followed by CE. The assay was linear between 2-250 ng/mL (R = 0.9998 for (S)-(+)-terbutaline and R = 0.9999 for (R)-(-)-terbutaline) and detection limit was 0.8 ng/mL. The intra-day variation ranged between 6.3 and 14.5% in relation to the measured concentration and the inter-day variation was 8.2-20.1%. It has been applied to the determination of (S)-(+)-terbutaline and (R)-(-)-terbutaline in urine from healthy volunteer dosed with racemic terbutaline sulfate.

• 대한화학회지
• /
• 제46권5호
• /
• pp.412-429
• /
• 2002

(+)(18crown6)-tetracarboxylic acid ($18C6H_4$)를 퀴놀린계 항생제인 gemifloxacin을 모세관 전기영동법으로 키랄 분리하였다. Body fluid에서 퀴놀린계 항생제인 gemifloxacin의 직접적인 분석은 빠른 분석 시간, 다성분 분석등의 여러 가지 장점을 가진다. 그러나 Body fluid내의 높은 농도의 나트륨 이온은 $18C6H_4$와 강한 전하 상호작용으로 인하여 gemifoxacin과 $18C6H_4$의 상호작용을 방해한다. 키랄 선택제와 나트륨 이온 사이의 상호 작용을 줄이기 위해 완충 용액에 킬레이트 리간드 EDTA를 첨가하였다. 시료 용액에 150mM의 나트륨 이온이 존재 할 때에도 분리 효율의 향상과 이동 시간의 감소를 관찰 할 수 이었다.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.276.2-276.2
• /
• 2003

Simultaneous enantioseparation of nine racemic non-steroidal antiinflammatory drugs (NSAIDs) for their accurate chiral discrimination was achieved by cyclodextrin (CO) modified capillary electrophoresis in the normal polarity (NP) mode and in the reversed polarity (RP) mode. The NP mode employed neutral tri-O-methyl-${\beta}$-cyclodextrin (TM${\beta}$CD) as a selector dissolved in MES buffer (PH 6.0). (omitted)

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.215.1-215.1
• /
• 2002

• 분석과학
• /
• 제36권4호
• /
• pp.143-151
• /
• 2023

Considering the greater role of α-amino acids in our daily lives, the enantiomer resolution of seven α-amino acids derivatized with fluorogenic reagent (4-fluoro-7-nitro-2,1,3-benzoxadiazole, NBD-F) by chiral HPLC on amylose or cellulose trisphenylcarbamate derived chiral stationary phases (CSPs) under simultaneous ultraviolet (UV) and fluorescence (FL) detection was performed. The degree of enantioseparation and resolution was affected by nature and selector backbones of the CSPs as well as the kind of amino acids. Baseline enantiomer separation and resolutions were observed for the enantiomers of all analytes as NBD derivatives especially on coated type amylose tris(3,5-dimethylphenylcarbamate) derived CSPs (Chiralpak AD-H and Lux Amylose-1). The other CSPs also showed good enantioselectivity except for the CSPs (Chiralpak IB, Chiralcel OD-H and Lux Cellulose-1) having cellulose tris(3,5-dimethylphenylcarbamate) as chiral selectors. The developed analytical chiral method was applied to determine the enantiomeric purity of seven commercially available L-α-amino acids and the impurities as D-forms were found to be in the range 0.08-0.87 %, respectively. The intra- and interday accuracy and precision assays showed high accuracy and precision of the developed analytical method. This chiral HPLC method for the enantiomer resolution of amino acids using fluorescent derivatization could be useful for the determination of enantiomeric purity of pharmaceuticals and biological study for amino acid type compounds among chiral drugs.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.278.3-279
• /
• 2003

A chiral stationary phase (CSP) prepared by bonding (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) to aminopropyl silica gel by HPLC was used in resolving several racemic drugs containing primary amino moiety. Most compounds used in this study were resolved on the CSP using 80％ methanol in water (V/V) containing 10mM sulfuric acid as a mobile phase. These results on the CSP were compared to those on the similar CSP derived from 18-C-6-TA of the same chiral selector by different connecting method.

• Bulletin of the Korean Chemical Society
• /
• 제31권1호
• /
• pp.82-86
• /
• 2010

Quinine (QN) is a weak anion-exchange type chiral selector and QN-based silica stationary phases have been widely used for enantioseparation of acidic chiral analytes in HPLC and recently in CEC. In this work we report enantioseparation of non-acidic chiral analytes on a quinine carbamate-immobilized zirconia (QNZ) in reversed-phase (RP) CEC. Influences of pH, composition of the buffer, acetonitrile content and the applied voltage on enantioseparation were examined. Enantiomers of the analytes investigated are well separated in acetonitrile/phosphate buffer mobile phases. Separation data on QNZ were compared to those on QN-bonded silica (QNS). Retention was longer but better enantioselectivity and resolution were obtained on QNZ than QNS.