Determination of Enantiomer Excess of Asymmetric Hydroesterification Reaction by Hplc using A Cellulose Tribenzoate Chiral Column

Purpose. This study describes the development of a rapid and sensitive LC-ESI-MS assay for simultaneous enantioselective determination of levocetirizine and pseudoephedrine in dog plasma in the presence of dextrocetirizine. Methods. Separations were achieved on an Ultron ES-OVM chiral column using the mobile phase consisting of 10 mM aqueous NH4OAc (pH 6.6) and acetonitrile (9:1 v/v). Results. The retention times of pseudoephedrine, dextrocetirizine, levocetirizine and diazepam (internal standard) were 5.2, 8.3, 9.6 and 11.6 min, respectively, and the total run time was less than 15 min. The assay was validated to demonstrate the linearity, accuracy and precision, recovery and stability. The calibration curves were linear over the concentration range from 1 – 200 ng/mL for levocetirizine and from 5 – 1000 ng/mL for pseudoephedrine. Conclusions. The developed assay was successfully applied to a pharmacokinetic study after oral administration of the racemic cetirizine (0.5 mg/kg, or 0.25 mg/kg as levocetirizine) and pseudoephedrine (12 mg/kg) in the dog. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

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Enantiomeric determination of the plasma levels of omeprazole by direct plasma injection using high-performance liquid chromatography with achiral–chiral column-switching

Journal of Chromatography B ◽

10.1016/j.jchromb.2003.09.053 ◽

2003 ◽

Vol 798 (2) ◽

pp. 275-281 ◽

Cited By ~ 45

Author(s):

Q.B Cass ◽

V.V Lima ◽

R.V Oliveira ◽

N.M Cassiano ◽

A.L.G Degani ◽

...

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Plasma Levels ◽

High Performance ◽

Column Switching ◽

Chiral Column ◽

Plasma Injection

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Development and Validation of RP-Chiral HPLC Method for Determination of (R)-Enantiomer Excess Content in Efavirenz

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22755 ◽

2020 ◽

Vol 32 (9) ◽

pp. 2208-2212

Author(s):

CH. RAMESH ◽

DHARMASOTH RAMA DEVI DEVI ◽

M.N.B. SRINIVAS ◽

S. RADHA KRISHNA ◽

NAGARAJU RAJANA ◽

...

Keyword(s):

Limit Of Detection ◽

Hplc Method ◽

Chiral Hplc ◽

Reverse Phase ◽

Limit Of Quantification ◽

Column Temperature ◽

Enantiomer Excess ◽

Development And Validation ◽

Methyl Phenyl

simple, specific, linear, accurate and precise reverse phase chiral HPLC method was developed for the separation of efavirenz enantiomers by using the Lux Amylose-2 column containing amylose tris(5-chloro-2-methyl phenyl carbamate) as a stationary phase. The mobile phase consists of 0.1 % formic acid in water and acetonitrile (55:45, v/v). The flow rate was kept at 1.0 mL/min and the detection wavelength used 252 nm and the column temperature was set at 25 ºC. The limit of detection was 0.01 mg/mL and the limit of quantification was 0.04 mg/mL. The linearity calibration curve of (R)-enantiomer was shown well from the range of 0.04 mg/mL to 0.4 mg/mL. The values of the correlation coefficient were 0.999 and 0.999 for (R)-enantiomer and (S)-efavirenz, respectively. The percentage recoveries of (R)-enantiomer from efavirenz drug substance were ranged from 93.5% to 107.5%. The results demonstrated that developed RP-chiral HPLC method was simple, precise, robust and applicable for the estimation of (R)-enantiomer in efavirenz API. This method was validated in as per ICH Q2 (R1) and USP validation of compendial methods <1225>.

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Simple and Rapid HPLC Separation and Quantification of Flavonoid, Flavonolignans, and 2,3-Dehydroflavonolignans in Silymarin

Foods ◽

10.3390/foods9020116 ◽

2020 ◽

Vol 9 (2) ◽

pp. 116 ◽

Cited By ~ 3

Author(s):

Petrásková ◽

Káňová ◽

Biedermann ◽

Křen ◽

Valentová

Keyword(s):

Analytical Methods ◽

Fourth Century ◽

Preparative Chromatography ◽

Hplc Separation ◽

Silybum Marianum ◽

Chiral Column ◽

Disease Treatment ◽

First Time ◽

Analytical Separation

Herbal preparations from Silybum marianum have been used since the fourth century BC in liver disease treatment and against numerous other pathologies. Consumption of silymarin containing drugs and food supplements continues to increase. Precise, fast, reliable, and complex determination of all components of silymarin preparations is paramount for assessing its pharmacological quality. We present here simple and fast HPLC-DAD and LC-MS analytical methods for the determination and quantification of all known silymarin components, including 2,3-dehydroflavonolignans that has not been achieved so far. The first method, using a common C18 column, allows baseline separation of previously inseparable silychristin A, B, isosilychristin, and silydianin. Moreover, this method allowed detection of three so far unknown silymarin components. In addition, the first analytical separation of enantiomers of 2,3-dehydrosilybin was achieved using a Lux 3μ Cellulose-4 chiral column, providing even more accurate description of silymarin composition. 2,3-Dehydroflavonolignans were isolated for the first time from silymarin using preparative chromatography on C18 and ASAHIPAK columns, and 2,3-dehydrosilychristin and 2,3-dehydrosilybin were for the first time conclusively confirmed by HPLC, MS, and NMR to be silymarin components. Using the optimized analytical methods, six various silymarin preparations were analyzed showing substantial differences in the composition.

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