Development of a New RP-UPLC Method for the Determination of Rabeprazole Sodium in Pharmaceutical Formulation and Application in Dissolution Studies

Purpose: To develop a reverse phase ultra-performance liquid chromatographic (RP-UPLC) method for the estimation of rabeprazole sodium in tablet formulations.Methods: Chromatographic separation was achieved on a Waters Acquity BEH C18 (50 x 2.1 mm, particle size 1.7 μm) column using an isocratic method with mobile phase composed of acetonitrile and phosphate buffer (pH 7.4) in the ratio of 35:65 (v/v). The flow rate was 0.4 ml/min, temperature of the column was maintained at ambient, injection volume was 5 μL and detection was made at 280 nm. The run time was as short as 2 min. Comparison of system performance with conventional HPLC was made with respect to analysis time, efficiency and sensitivity.Results: The developed method was linear for rabeprazole sodium from 0.03 - 30 μg/ml and the linear regression obtained was > 0.999. Precision, evaluated by intra- and inter-day assay,s had relative standard deviation (R.S.D) values within 1.5 %. Recovery data were in the range 98.0 - 101.5 % with R.S.D. values < 1.5 %.Conclusion: The method is precise, accurate, linear, robust and fast. The short retention time of 1.49 min allows the analysis of a large number of samples in a short period of time and, therefore, should be cost-effective for routine analysis in the pharmaceutical industry.Keywords: Ultra performance liquid chromatography, Assay, Rabeprazole sodium, Validatio

Adsorption of fluoride ions onto naturally occurring earth materials

Batch sorption system using two naturally occurring earth materials (EM) as adsorbents was investigated to remove fluoride ions from aqueous solution. The system variables studied include initial concentration of the sorbate, agitation time, adsorbent dose, pH, co-ions and temperature. The experimental data fitted well to the Freundlich isotherm. The amount of fluoride ions adsorbed per unit mass of the adsorbent was found to be 0.011 and 0.007 mg/g, at 30 °C from 4 mg/L fluoride solution, for EM1 and EM2 respectively. Thermodynamic parameters such as ΔH°, ΔS° and ΔG° were calculated which indicates that the removal of fluoride ions is an endothermic process. Kinetic studies reveal that the adsorption follows reversible first order kinetics. X-ray diffraction patterns of the adsorbents before and after adsorption and Dubinin-Radushkevick (D-R) isotherm indicate that the adsorption of fluoride ions onto these materials is a physisorption process. @ JASEMJ. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 90 - 9

Development of a New RP-UPLC Method for the Determination of Rabeprazole Sodium in Pharmaceutical Formulation and Application in Dissolution Studies

Purpose: To develop a reverse phase ultra-performance liquid chromatographic (RP-UPLC) method for the estimation of rabeprazole sodium in tablet formulations. Methods: Chromatographic separation was achieved on a Waters Acquity BEH C18 (50 x 2.1 mm, particle size 1.7 μm) column using an isocratic method with mobile phase composed of acetonitrile and phosphate buffer (pH 7.4) in the ratio of 35:65 (v/v). The flow rate was 0.4 ml/min, temperature of the column was maintained at ambient, injection volume was 5 μL and detection was made at 280 nm. The run time was as short as 2 min. Comparison of system performance with conventional HPLC was made with respect to analysis time, efficiency and sensitivity. Results: The developed method was linear for rabeprazole sodium from 0.03 - 30 μg/ml and the linear regression obtained was > 0.999. Precision, evaluated by intra- and inter-day assay,s had relative standard deviation (R.S.D) values within 1.5 %. Recovery data were in the range 98.0 - 101.5 % with R.S.D. values <1.5 %. Conclusion: The method is precise, accurate, linear, robust and fast. The short retention time of 1.49 min allows the analysis of a large number of samples in a short period of time and, therefore, should bevcost-effective for routine analysis in the pharmaceutical industry

Development and Validation of a Stability-Indicating RP-HPLC Method for Simultaneous Determination of Paracetamol, Tramadol HCl and Domperidone in a Combined Dosage Form

Purpose: To develop a stability indicating RP-HPLC method for a combination drug product containing a high dose of paracetamol (PR) and low doses of domperidone (DM) and tramadol HCL (TR). Methods: The analytes are well separated by a reverse phase column and an isocratic mobile phase consisting of 0.1 %v/v trifluoroacetic acid: acetonitrile: methanol in the ratio 70:25:5 (v/v) with a flow rate of 1.0 mL/min. The effluent was monitored at 272 nm. The drug products were subjected to stress conditions of acid, base, peroxide, thermal and photolytic degradation and peak homogeneity of PR, TR and DM were obtained using photo diode array detector. Results: The degradation products were well resolved from PR, TR and DM peaks, thus indicating the stability-indicating nature of the method. The assay was linear from 165 – 495 μg/mL for PR, 18.75 – 56.25 μg/mL for TR, and 5 – 15 μg/mL for DM. Although the tablet contained high and low doses of the drugs, the intra- and inter-day variations were <2.0 %. Conclusion: The proposed method was validated according to the ICH guidelines and proved suitable for stability and homogeneity testing, as well as for quality control of the combined drugs in pharmaceutical preparations