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Determination of nilotinib in spiked plasma, urine, and capsules by high-performance liquid chromatography with fluorimetric detection

Yilmaz E. M., Aydoğmuş Z., Aboul-Enein H. Y.

Acta Chromatographica

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2016

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Vol. 28, no. 3

313--331

EN

A precise and sensitive reversed phase high-performance thin-layer chromatography (RP-HPLC) method was developed for the determination of nilotinib (NTB) in spiked plasma, urine, and pharmaceutical capsule formulation. The method was based on derivatization NTB with 4-chloro-7-nitrobenzofurazan (NBD-Cl) in the borax buffer (pH 9). The method employs an isocratic elution using acetonitrile and 10 mM orthophosphoric acid (40:60 v/v) as a mobile phase and an C18 column (4.6 mm × 250 mm, 5 μm, Waters Symmetry), with a fluorescence detector (λex: 447 nm, λem: 530 nm). The method validation was performed with respect to linearity, recovery, accuracy, precision, and stability. The linear ranges were 100–600 ng mL−1 in standard solution, plasma, and urine. Correlation coefficients (r2) were higher than 0.9997 for all of the analytes, indicating good linear relationship. The percentage recovery was 87.89% for plasma, 95.35% for urine, and 96.07% for capsules.

2

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

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2011

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Vol. 23, no. 3

389--401

EN

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.

3

A potentiometric, enantioselective membrane electrode for S-Ramipril assay

Stefan R.-I., Staden J. F. van, Baiulescu G.-E., Aboul-Enein H. Y.

Chemia Analityczna

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1999

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Vol. 44, No. 3A

417-422

EN

A potentiometric, enantioselective membrane electrode based on graphite paste (graph-ite powder and paraffin oil), impregnated with 10(-3) mol 1(-1) 2-hydroxy-3-trimethyl-ammoniopropyI-13-cycIodextrin (as chloride salt) solution, is proposed for S-ramipril assay. This sensor can be used reliably for the assay of S-ramipril as raw material (enantiopurity tests), as well as in its pharmaceutical formulations, in the concentration range from 1.80 x 10(-5 ) to 2.3 x 10(-1) mol 1(-1) , with a detection limit of I x 10-5 moll-] , and with an average recovery of 99.94% (RSD = 0.030%) (recovery test), employing the potentiometric technique. The enantioselectivity was determined versus D-proline. It was shown that L-proline is the only main interfering compound. The surface of the elec-trode can be regenerated by simply polishing it to obtain a fresh surface which is ready to be used in a new assay.

PL

Potencjometryczna enancjoselektywna elektroda membranowa wykorzystująca pastę grafitową (proszek grafitowy z olejem parafinowym) impregnowaną 10-3 mol 1(-1) 2-hydroksy-3-trimetyloamoniopropylo-13-cyklodekstryną (w postaci soli chlorkowej) została zaproponowana do oznaczania S-Ramiprylu. Czujnik ten może być wiarygodnie zasto-sowany do oznaczania S-Ramiprylu w surowcu (próby enancjoselektywności) jak i w preparatach farmaceutycznych. Zakres oznaczalności wynosi od I ,80 x 10-5 moll-1 do 2,3 x 10-1 moll-l, granica wykrywalności -I x 10-5 moll-l. Średni odzysk wynosi 99,94%, względne odchylenie standardowe -0,030%. Enancjoselektywność została sprawdzona w stosunku do D-proliny. Wykazano, że jedynym istotnym interferentem jest L-prolina. Powierzchnia elektrody może być regenerowana przez jej szlifowanie w celu odnowienia elektrody przed następnym oznaczeniem.