• Archives of Pharmacal Research
• /
• v.23 no.1
• /
• pp.26-30
• /
• 2000

The enantiomers of the bronchodilator terbutaline were separated by reversed-phase high performance liquid chromatograhy after derivatization with 2,3,4,6-tetra-O-acetyl-\beta-D-glucopyranosyl isothiocyanate(GITC) reagent. The derivatization proceeded quantitatively within 1 h at room temperature. The corresponding diastereomeric thiourea derivatives were well resolved on an ODS column with acetonitrile-acetate buffer as a mobile phase. Elution orders of the diastereomers were confirmed by derivatization of R-(-)-terbutaline and S-(+)-terbutaline which were collected by semi-preparative chiral HPLC using Sumichiral OA-4700 column. The native fluorescence of terbutaline was quenched by derivatization with GITC. The detection limit was 25ng when monitored at UV 278 nm.

• Archives of Pharmacal Research
• /
• v.20 no.5
• /
• pp.486-490
• /
• 1997

A stereospecific HPLC method has been developed for the resolution of the enantiomers of salbutamol in human urine. After solid-phase extraction and derivatization with (S)-(-)-${\alpha}$-methyl-benzyl isocyanate, the diastereomeric derivatives were resolved $(R_s=1.59)$ on $5{\mu}M$ octadecylsilan column using 47% methanol as a mobile phase with fluorescence detection. The detection limit of each enantiomer was 10 ng/ml (S/N=3).

• Bulletin of the Korean Chemical Society
• /
• v.24 no.2
• /
• pp.239-242
• /
• 2003

• Archives of Pharmacal Research
• /
• v.21 no.2
• /
• pp.217-222
• /
• 1998

A stereospecific HPLC method has been developed for the resolution of the enantiomers of salbutamol in human urine. After solid-phase extraction and derivatization with 2,3,4,6-tetra-O-acetyl-$\beta$-D-glucopyranosyl isothiocyanate, the diastereomeric derivatives were resolved (Rs=1.83) on $5{\mu}m$ octadecylsilan column using 35% acetonitrile in 0.05M ammonium acetate buffer (pH=6) as a mobile phase with electrochemical detection. The diastereomeric derivatives were formed within 30 min. The detection limit of each enantiomer was 20 ng/ml (S/N=3).

• Archives of Pharmacal Research
• /
• v.27 no.1
• /
• pp.35-39
• /
• 2004

The method for the chiral analysis of (-)-yatein was developed and the distribution of this component in the plants of three genera like Juniperus, Thuja and Chamaecyparis belonging to Cupressaceae family was examined. The chiral analysis of (-)-yatein from the plants was carried out by high performance liquid chromatography on (R,R)-Whelk-O1 column using 81 v/v% methanol as mobile phase. The yatein content in the leaves of Juniperus was the highest in compare with that of the other two genera, providing the possibility of the chemical discrimination of the plants in Juniperus from the other plants in the Cupressaceae family. In general, the yatein content in the leaves was much higher than that in the twigs. This method could be applied for the quality control of (-)-yatein in the plants belonging to Cupressaceae family.

• Journal of the Korean Chemical Society
• /
• v.39 no.2
• /
• pp.138-141
• /
• 1995

• Archives of Pharmacal Research
• /
• v.27 no.9
• /
• 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.

• Journal of the Korean Chemical Society
• /
• v.49 no.3
• /
• pp.283-287
• /
• 2005

• KSBB Journal
• /
• v.20 no.3
• /
• pp.244-249
• /
• 2005

Chiral separation of racemic ibuprofen was achieved on a Kromasil KR100-5CHI-TBB column. Some chromatographic parameters (resolution, number of theoretical plates, HETP, capacity factor) are calculated under different separation conditions such as change of mobile phase compositions (hexane / t-BME : 85 / 15, 75 / 15, 65 / 35, 55 /45) as well as acetic acid concentrations for adjusting pH (0.1 to 1 $v/v\%$). Flow rate versus number of theoretical plates and HETP were compared to evaluate column efficiency. To determine the adsorption isotherms, PIM (Pulsed Input Method) was carried out. At concentrations of racemic ibuprofen between 0.1 and 0.3 mg/ml, S- and R-ibuprofen have the same retention time of 4.48 and 5.81 min. Ibuprofen isotherms show a linear form under concentrations of 0.3 mg/ml with eluent (hexane / t-BME = 55 / 45).

• Bulletin of the Korean Chemical Society
• /
• v.28 no.6
• /
• pp.1070-1072
• /
• 2007