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HPLC determination of enantiomeric thiazolidine-2-carboxylic acid on chiral stationary phase with pre-column derivatization

Zhang Y., Peng Q., Zeng H., Yao S, Zhang Y., Song H.

Acta Chromatographica

2013

Vol. 25, no. 2

287--296

A new high-performance liquid chromatography (HPLC) method has been developed and validated for determination of enantiomeric purity of thiazolidine-2-carboxylic acid within a short run time of less than 10 min. The method was based on pre-column derivatization of thiazolidine-2-carboxylic acid with aniline, and complete separation of enantiomers has been achieved on a Chiralcel OD-H analytical column (250 × 4.6 mm) using n-hexane-isopropanol (85:15 v/v) as mobile phase at a flow rate of 1.0 mL min-1 under UV and optical rotation (OR) detection. Detection wavelength was set at 254 nm. Then the effects of mobile phase and temperature on enantioselectivity were further evaluated. The method was validated with respect to precision, accuracy, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The recoveries were between 98.5 and 101.3% with percentage relative standard deviation less than 1.16%. The LOD and LOQ for the aniline derivatives of (+)-thiazolidine-2-carboxylic acid were 4.9 and 16.4 μg mL-1 and for the aniline derivatives (−)-thiazolidine-2-carboxylic acid were 5.1 and 17.2 μg mL-1, respectively.

Oznaczanie czystości enancjomervcznej oraz kontrola międzyoperacyjna metodą HPLC w technologii wytwarzania optycznie czynnej substancji aktywnej na przykładzie winianu tolterodyny

Puchalska M., Zagrodzka J., Czerniec-Michalik E., Zezula M., Chmiel J., Łuniewski W., Zagrodzki B.

Przemysł Chemiczny

2012

T. 91, nr 3

358-364

Przedstawiono izokratyczną chiralną metodę HPLC z detekcją UV stosowaną do oznaczania czystości enancjomerycznej L-(+)-winianu (R)-tolterodyny. Metodę zastosowano do kontroli międzyoperacyjnej procesu oczyszczania oraz do badania substancji aktywnej otrzymywanej w technologii opracowanej w Instytucie Farmaceutycznym. Opracowane procedury analityczne zostały zwalidowane zgodnie z wytycznymi ICH.

Applicability of the isocratic chiral high-performance liq. chromatog. with UV detection for detn. of the enantiomeric purity of active pharmaceutical ingredients was successfully tested on an example of (R)-2-[3-(diisopropylamino)- 1-phenylpropyl]-4-methylphenyl L-(+)-tartarate. Contents of both (R) and (S) isomers were detd.

Enantioselective separation and determination of citalopram enantiomers in pharmaceutical dosage form and bulk drug using experimental design approach on Chiralcel® OC as a chiral stationary phase

Semreen M. H, Aboul-Enein H. Y.

Acta Chromatographica

2011

Vol. 23, no. 3

389--401

An enantioselective HPLC method was developed and validated for the separation and the estimation of citalopram (CIT) enantiomers in bulk drug and pharmaceutical preparations. The method was validated for its linearity (correlation coefficient = 0.9994 and 0.996 for S-(+)-enantiomer and R-(−)-enantiomer, respectively), accuracy, robustness, and intermediate precision. Experimental design was applied during intermediate precision (full factorial 2 3 design) and robustness testing (Box Benken as a factorial design), for robustness test three factors were considered: percentage of organic modifier, flow rate, and temperature. The separation was achieved on cellulose tris(phenylcarbamate) known as Chiralcel® OC (25 cm, 4.6 mm i.d.) derivatized cellulose (phenyl carbamate), with UV detection at 245 nm using n-hexane-isopropanoldiethylamine (85:15:0.2, υ/υ/υ) as mobile phase at flow rate 0.7 mL min−1. A decrease in the flow rate results in decreasing the selectivity factor (α), while varying the percentage of n-hexane and the temperature have no effect on selectivity factor (α). For intermediate precision, the variables considered were analyst, equipment, and day. The RSD% value (0.73%, n = 24) indicates a good precision for the analytical procedure. The method was found to be suitable for determination of enantiomeric purity of CIT in bulk drugs and pharmaceutical formulations.