Determination of citalopram in tablets by capillary zone electrophoresis and by direct and derivative UV-spectrophotometry.

Three rapid, simple and accurate analytical methods for the determination of citalopram in tablets were developed. The capillary zone electrophoresis (CZE) method was carried out using fused silica capillary with 67 mM phosphate buffer pH 7.0 as the background electrolyte, 30 kV of separation voltage and UV detection at 239 nm.

Separation of fibrate-type antihyperlipidemic drugs by capillary electrophoresis and their quantitation in pharmaceuticals.

Six antihyperlipidemic agents-bezafibrate, ciprofibrate, clofibrate, clofibric acid, fenofibrate and gemfibrozil were separated by means of capillary electrophoresis, using unmodified fused silica tubing of 75 microm internal diameter and 87 cm length (65 cm to the UV detector at 227 nm). Migration time and selectivity were examined in differing pH of separation buffer, varying separation voltage and differing temperature. Optimal separation was achieved using 1/15 M phosphate buffer pH 10, 240 V/cm at 25 degrees C.

Determination of fenofibrate and gemfibrozil in pharmaceuticals by densitometric and videodensitometric thin-layer chromatography.

New thin-layer chromatography (TLC) methods with densitometric and videoscanning detection were elaborated for the quantitative determination of fenofibrate in Fenoratio capsules and gemfibrozil in Gemfibral tablets. Analysis was performed on high-performance TLC diol F254 plates using hexane-tetrahydrofuran (8 + 2, v/v) mobile phase in horizontal DS chambers using the sandwich technique. The active substances were extracted from tablets with methanol.

Study of the liquid chromatography retention of some fibrate-type antihyperlipidemic drugs on C18 and CN columns: application for quantitation in pharmaceutical formulations.

The 6 antihyperlipidemic agents-bezafibrate, ciprofibrate, clofibrate, clofibric acid, fenofibrate, and gemfibrozil-were separated on octadecyl (C18) and cyano (CN) chemically bonded columns using mobile phases containing phosphate buffer and different amounts of acetonitrile, dioxane, propan-2-ol, methanol, and tetrahydrofuran. Relationships between log k values and mobile phase composition have been examined for these systems. Analysis was performed on a Waters LC system with Merck LichroCART C18 and CN 125 mm columns using a flow rate of 1 mL/min and 227 nm detection.

Application of UV-derivative spectra for determination of four antihyperlipidaemic drugs in pharmaceutical formulations.

A method for the determination of bezafibrate, ciprofibrate, fenofibrate and gemfibrozil in pharmaceutical formulations by first-, second- and third- derivative spectrophotometry is described, using "peak-peak" and "peak-zero" measurements. The calibration graphs were linear in the range 2-20 microg x mL(-1) for all the compounds investigated. No interference was found from tablet excipients at the selected wavelengths and assay conditions.

Rapid and simple high-performance liquid chromatographic determination of felbamate in serum.

An isocratic high-performance liquid chromatographic method for the quantitation of felbamate in serum is presented. The method is based on protein precipitation with acetonitrile and reversed-phase chromatography with spectrophotometric detection at 210 nm. The separation was performed on a Nova-Pak C18 column and the mobile phase consisted of acetonitrile-water (1:4, v/v).

LC determination of moclobemide and three metabolites in plasma.

Moclobemide and three metabolites were quantified using 1 ml of plasma and solid-phase extraction with Bakerbond CN column after the addition of nadolol as the internal standard (I.S.).

Development and validation of a HPLC method for the determination of cetirizine in pharmaceutical dosage forms.

A rapid, simple and accurate HPLC method is described for the assay of cetirizine in commercial dosage forms. Methanol was found to be a suitable extraction solvent for tablets and for preparing solutions from drops and oral liquids. The samples were chromatographed on a Nova-Pak C18 column and UV detected at 227 nm.

Applications of derivative UV spectrophotometry for the determinations of cetirizine dihydrochloride in pharmaceutical preparations.

A method for the determination of cetirizine dihydrochloride in pharmaceuticals by first-, second-, third- and fourth- order derivative spectrophotometry is described, using "peak-peak" (P-P), and "peak-zero" (P-0) measurements. The calibration curves are linear within the concentration range of 7.5-22.

Determination of moclobemide, paroxetine, and fluvoxamine in tablets by HPLC.

A simple, accurate high performance liquid chromatography procedure is presented in order to determine moclobemide in Aurorix-tablets, paroxetine in Seroxat-tablets and fluvoxamine in Fevarin tablets. These drugs were chromatographed on a Nova-Pak C18, (dp = 4 microm), 150x3.9 mm i.

Thin-layer chromatographic analysis of fludarabine and formycin A in human plasma.

Fludarabine and formycin A, extracted from plasma, were separated by TLC method on silica gel and aluminium oxide by horizontal development, using suitable mobile phases. The substances were visualized by UV irradiation. After extraction from plasma it was possible to detect 100 ng of fludarabine and 200 ng of formycin A.

Determination of zopiclone in tablets by HPLC and UV-spectrophotometry.

Rapid, simple and accurate chromatographic (HPLC) and spectrophotometric methods for the determination of zopiclone in tablets were elaborated. Acetonitrile was found to be a suitable extraction solvent. The samples were chromatographed on Nova-Pak C18 column and UV detection at 304 nm.

High-performance liquid chromatographic assay of formycin A in plasma after solid-phase extraction.

A new, simple and accurate high-performance liquid chromatography (HPLC) method for the determination of formycin A in plasma is presented. The samples were chromatographed on a LiChrosórb RP-18 column after purification using a Bakerbond SPE column. The mobile phase was methanol-0.

Preliminary pharmacokinetic studies of Ukrain in rats.

Ukrain (thiophosphoric acid derivative of Chelidonium majus L. alkaloids) was administered to rats i.p.

Determination of fluoxetine in human plasma using reserved phase HPLC.

A rapid, simple, accurate method for the determination of fluoxetine in human plasma is presented. Liquid-liquid extraction of fluoxetine was carried out using diethyl ether. Chlorprothixene was applied as an internal standard.

Chromatographic analysis (TLC) of fluoxetine, doxepine, imipramine and opipramol in human plasma.

Fluoxetine, imipramine, doxepine and opipramol after liquid-liquid extraction were separated by TLC on silica gel 60 GF254 by ascending and horizontal technique using suitable mobile phases. The substances were identified by UV irradiation at 254 nm and by spraying of Amelinka's reagnet (up to the amount 0.25 microgram fluoxetine and 0.

Determination of fludarabine phosphate in human plasma using reversed phase high-performance liquid chromatography.

A rapid, simple and accurate HPLC method for the determination of fludarabine phosphate in human plasma is presented. Fludarabine phosphate from plasma was successfully purified. The samples were chromatographed on a LiChrosorb RP-18 (10 microns) column after purification using a Bakerbond Spe column.

Chromatographic analysis (TLC) of uracil arabinoside, cytosine arabinoside, uracil and cytosine in human plasma.

Cytosine arabinoside, uracil arabinoside, cytosine and uracil after solid-phase extraction from plasma with minicolumns Adsorbex were separated by TLC on silica gel 60 GF254 by ascending and horizontal technique using suitable mobile phases. The substances were identified by UV irradiation at 254 nm and by spraying of 1% KMnO4 solution (up to the amount 500 ng analysed substances).

Determination of aprindine in human plasma using reversed phase HPLC.

A rapid, simple, accurate method is presented for the determination of aprindine in human plasma. Liquid-liquid extraction of aprindine was carried out using diethyl ether. Amiodarone was applied as an internal standard.

Determination of nadoxolol in human plasma using reversed-phase high-performance liquid chromatography.

A rapid, simple and accurate HPLC method is presented for the determination of nadoxolol in human plasma. Nadoxolol from plasma was successfully purified using an Adsorbex column. The samples were chromatographed on a LiChrosorb RP-18 (10 microns) column with methanol-acetonitrile-phosphate buffer (pH 3.

Chromatographic analysis (TLC) aprindine and nadoxolol in human plasma.

Aprindine and nadoxolol extracted from plasma were separated by TLC method on silica gel by ascending technique on 5 x 20 cm and 2.5 x 7.5 cm microscopic slides and also by horizontal development, using suitable mobile phases.

Determination of amiodarone in tablets and plasma by high-performance liquid chromatography.

A method is described for measuring amiodarone in human plasma and tablets using a LiChrosorb RP-18 column, a mobile phase methanol-acetonitrile-phosphate buffer pH 2.6 (80:15:5, v/v) and UV detection at 254 nm. Another antiarrhythmic drug - aprindine was used as an internal standard (i.

[Determination of methadone in plasma using high pressure liquid chromatography methods].

High-performance liquid chromatography on the column of LiChrosorb RP-18 was applied to the determination of methadone in plasma, after previous precipitation of proteins with methanol and extraction from alkalized plasma with diethyl ether. Methadone, ion-paired with pentane-1-sulphonic acid added in a mobile phase acetonitrile-methanol-ammonium acetate solution (20:58:22), was monitored at 254 nm. Piritramide was used as an internal standard.