A Validated HPLC Method with Fluorescence Detection for the Determination of Droperidol in Pharmaceutical Tablets,Human Serum,and Human Milk

A sensitive and simple HPLC method with fluorimetric detection has been developed for determination of droperidol in pharmaceutical tablets, human serum, and human milk. Chromatography was performed on a 100 mm × 3 mm i.d. C₁₈ column with methanol–water, 30:70 (v/v), pH 3.5, as mobile phase at a flow-rate of 0.8 mL min⁻¹. The injection volume was 5 μL and detection was by monitoring emission at 324 nm after excitation at 283 nm. Droperidol and p-hydroxybenzoic acid (internal standard) eluted after 5.3 and 6.1 min, respectively. The method was validated over the concentration range 1.14 × 10⁻⁷ to 9.12 × 10⁻⁶ M. Selectivity was good and the limits of detection and quantitation of the method were approximately 3.54 × 10⁻⁸ and 1.07 × 10⁻⁷ M, respectively, corresponding to 13 and 40 ng mL⁻¹. The applicability of the method to determination of droperidol in pharmaceuticals, human serum, and human milk was demonstrated.

     

An LC Method for the Determination of Bupropion and Its Main Metabolite, Hydroxybupropion in Human Plasma

A new LC method has been developed and validated for the direct determination of bupropion and its main metabolite, hydroxybupropion in human plasma. Plasma samples were analyzed after a simple, one step protein precipitation with trichloroacetic acid using a C₈ column and mobile phase, consisting of methanol/acetonitrile/phosphate buffer (10 mM, pH 3.0) (40:10:50, v/v/v) and 20 mM 1-heptane sulfonic acid sodium salt with carbamazepine as the internal standard. UV detection was performed at 214 and 254 nm. The method was validated over the concentration range of 60–2,400 and 150–4,700 ng mL^?1 for bupropion and hydroxybupropion, respectively. The intra- and inter-day assay variability was less than 15% for the two analytes. Limit of detection values were 24.8 and 63.4 ng mL^?1 for bupropion and hydroxybupropion, respectively. The method developed was applied to quantification of bupropion and hydroxybupropion in human plasma.     

A Validated Thin-Layer Chromatographic Method for Analysis of Bupropion Hydrochloride in a Pharmaceutical Dosage Form

JPC – Journal of Planar Chromatography – Modern TLC - A simple and sensitive thin-layer chromatographic method has been established for analysis of bupropion hydrochloride in...     

An LC Method for the Determination of Bupropion and Its Main Metabolite,Hydroxybupropion in Human Plasma

A new LC method has been developed and validated for the direct determination of bupropion and its main metabolite, hydroxybupropion in human plasma. Plasma samples were analyzed after a simple, one step protein precipitation with trichloroacetic acid using a C₈ column and mobile phase, consisting of methanol/acetonitrile/phosphate buffer (10 mM, pH 3.0) (40:10:50, v/v/v) and 20 mM 1-heptane sulfonic acid sodium salt with carbamazepine as the internal standard. UV detection was performed at 214 and 254 nm. The method was validated over the concentration range of 60–2,400 and 150–4,700 ng mL⁻¹ for bupropion and hydroxybupropion, respectively. The intra- and inter-day assay variability was less than 15% for the two analytes. Limit of detection values were 24.8 and 63.4 ng mL⁻¹ for bupropion and hydroxybupropion, respectively. The method developed was applied to quantification of bupropion and hydroxybupropion in human plasma.

     

The determination of lansoprazole in pharmaceutical preparation by capillary electrophoresis

Summary A capillary electrophoretic method for the determination of lansoprazole in pharmaceutical preparations is described. The analysis was performed in a fused silica capillary using 20 mM borate buffer at pH 8.7 as a background electrolyte. The best resolution was obtained by applying a potential of 30 kV and vacuum injection of 1 s. Detection was made at 200 nm. Phenobarbital sodium was a good internal standard and the migration times were 4.1±0.2 min (lansoprazole) and 5.7±0.2 min (phenobarbital sodium). A well-correlated calibration equation was found in the range of 1.12×10⁻⁵ and 2.24×10⁻⁴ M. Limit of detection (LOD) and limit of quantitation (LOQ) were 1.4×10⁻⁶ M (RSD 1.44%) and 4.42×10⁻⁶ M (RSD 1.49%), respectively. The method was validated and applied to the capsules containing enteric coated pellets of lansoprazole. The results of the proposed method were compared those of UV spectrophotometry. Insignificant differences were found between the two methods at the 95% probability level. The described CE method is selective, rapid, sensitive and accurate for the analysis of lansoprazole in quality control laboratories.     

Determination of Sotalol in Tablets and Serum by CZE

A validated capillary zone electrophoretic method for analysis of sotalol is described. Analysis was performed in a fused-silica capillary with 20 mM phosphate buffer (pH 4.20) containing 10% (v/v) acetonitrile as background electrolyte. The applied potential was +20 kV, the injection time 0.08 min, signal detection was at 200 nm, and 3,4-dihydoxybenzylamine was used as internal standard. The method was validated over the concentration range 1.98 × 10⁻⁵ to 9.90 × 10⁻⁵ M; repeatability was good and there was no interference. Highly satisfactory results were obtained from analysis of tablets and serum, indicating the method is specific, accurate, and precise, and suitable for routine analysis of sotalol in pharmaceutical tablets and in pharmacokinetic studies.

     

CE Determination of Droperidol in Tablets and Human Serum

A capillary electrophoretic method was described for the determination of droperidol in pharmaceutical tablets and human serum. Droperidol and internal standard, lansoprazole, were separated on an uncoated fused-silica capillary using a run buffer containing borate (10 mM; pH 9.3) and aqueous methanol (20%, υ/υ). The signals were detected at 210 nm. The migration times for droperidol and internal standard were 2.1 and 2.9 min, respectively. The method has been validated in the range of 2.2 × 10^?5 ? 7.8 × 10^?5 M and applied to both tablets and human serum with good repeatability and no interference.     

Determination of Carbamazepine and its Main Metabolite Carbamazepine-10,11-Epoxide in Rat Brain Microdialysate and Blood Using ESI–LC–MS (Ion Trap)

A new analytical method has been developed and validated for determination of the anti-epileptic drug carbamazepine (CBZ) and its main metabolite carbamazepine-10,11-epoxide (CBZ-E) using ESI–LC–MS (ion trap). The compounds were separated on a C18 (150 × 2.1 mm I.D., 3 μm particles) column and were isocratically eluted in the mobile phase consisting of water–acetonitrile–acetic acid (74.5:25:0.5, v/v) using the flow rate of 0.4 mL min⁻¹. The other anti-epileptic drug oxcarbamazepine (OXC) was used as an internal standard. The retention times for CBZ-E, OXC and CBZ were 5.6, 6.8, 12.8 min. Signals of the compounds were monitored under multi-reaction monitoring mode (MRM) of ESI–LC–MS (ion trap) for the quantification. Selected ions of CBZ-E, OXC and CBZ in MRM were m/z 253→210, m/z 253→180 and m/z 237→194. The method was validated over the concentration range of 5.0–500.0 ng mL⁻¹ and was applied to rat brain microdialysate and blood samples for the determination of CBZ and main metabolite. The brain microdialysate and the blood sample were collected simultaneously after intra-peritoneal injection of CBZ (12 mg kg⁻¹) during a period of 10 h. No interference from endogenous substances and matrix effect were found on the separation of microdialysates and blood samples. The consequent signals of the compounds were resolved and integrated clearly. The LC–MS method was presented as an alternative to investigate pharmacokinetic parameters of CBZ and CBZ-E in blood and brain studies.