RP-HPLC

ABSTRACTA simple, accurate, precise, and cost-effective reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed and validated for the simultaneous estimation of Telmisartan and Cilnidipine in bulk and marketed tablet dosage form. Chromatographic separation was achieved using an Agilent C18 column (250mm × 4.6mm, 5 ?m) with a mobile phase consisting of Acetonitrile and phosphate buffer (pH 3.0) in a 90:10 v/v ratio, at a flow rate of 1.0 mL/min and detection wavelength of 254 nm. Method validation followed ICH Q2 (R1) guidelines for system suitability, linearity, accuracy, precision, robustness, LOD, and LOQ. The method showed linearity over the range of 40–240 ?g/mL for Telmisartan and 10–60 ?g/mL for Cilnidipine, with correlation coefficients (R²) of 0.9998 for both drugs. The method was found to be accurate, precise (%RSD < 2%), robust, and suitable for routine quality control analysis in pharmaceutical formulations. Keywords: Telmisartan, Cilnidipine, RP-HPLC, Method Validation, ICH Q2(R1), Fixed-Dose Combination

ABSTRACTThe objective of the study was to develop and evaluate the reverse phase high performance liquid chromatography (RP-HPLC) method for the quantitative determination of potential impurities of Mirabegron active pharmaceutical ingredient. The method uses Puratis C18 column (250 × 4.6mm, 5µm ) with mobile phase A consisted, 20 mM Ammonium acetate, pH adjusted to 4.5 and mobile phase B consisted methanol  with a gradient programme. The column temperature was maintained at 25 °C and the detection was carried out at 247 nm. Efficient and reproducible chromatographic separation was achieved on C18 stationary phase in gradient elution profile. The newly developed HPLC method was validated according to ICH guidelines considering three impurities to demonstrate precision, linearity, accuracy and robustness of the method. The developed HPLC method was found to be accurate and sensitive. The correlation coefficient values are greater than 0.99 for Mirabegron and its three impurities. Detection limit and quantitation limit was 0.04ppm and 0.14ppm respectively, indicating the high sensitivity of the newly developed method. Accuracy of the method was established based on the recovery obtained between 99.67% and 104.98% for all impurities. The result of robustness study also indicates that the method is robust and is unaffected by small variation in chromatographic conditions. The proposed HPLC method provides reliable, reproducible, accurate and sensitive for the quantification of Mirabegron related substances. Keywords: Mirabegron; Impurities; RP-HPLC; Validation.

ABSTRACTAn efficient and simple RP-HPLC method has been developed and validated for simultaneous determination of Repaglinide (REPA) and Metformin Hydrochloride (MET). The separation was carried out using mobile phase consisting of Phosphate buffer: Methanol (30:70). The column was used Luna 5u C18 (2) 100A of size 0.25m *4.6mm with flow rate of 1.0 mL/min. Drug peaks were well separated and were detected by a UV detector at 260 nm.. The described method was linear over concentration range of 10-50 ppm for assay of REPA and MET. The retention time of REPA and MET was found to be 4.31. The method has been validated according to ICH guidelines with respect to system suitability, specificity, precision, accuracy, ruggedness and robustness. Metformin limit of detection (LOD) and limit of quantification (LOQ) were 0.0386 mg/ml and 0.1169mg/ml respectively while LOD and LOQ for Repaglinide were 0.0339?g/ml and 0.1025?g/ml respectively and thus can be successfully applied for the routine analysis of REPA and MET in bulk and marketed dosage forms. Keywords: Repaglinide, Metformin Hydrochloride, RP-HPLC, Simultaneous estimation, Validation

ABSTRACTThe Chromatographic condition were successfully developed for the separation of Acyclovir and     Hydrocortisone by using Agilent C8 column (25 cm x 4.6 mm i.d., 5 ?). A simple, selective, rapid, precise and economical reverse phase high performance liquid chromatographic method has been developed for the simultaneous estimation of Hydrocortisone and Acyclovir from pharmaceutical formulation. The method was carried out on a C8 (25 cm x 4.6 mm i.d., 5 ?) column with a mobile phase consisting of Methanol: water (adjusted to pH 3.0 using o-phosphoric acid) in the ratio of 80:20 v/v. The retention time of  Hydricortusone and Acyclovir was 3.50 min and 6.00 min respectively with the flow rate of 1mL/ min. Eluents were detected at 254 nm.  The linear regression analysis data for the linearity plot showed good linear relationship with correlation coefficient value for Hydrocortisone and Acyclovir were R2=0.9995 and R2=0.9996 in the concentration range of 10-40µg. mL-1 , 20-80 µg. mL-1 respectively. The relative standard deviation for intra-day precision was lower than 2.0 %. The method was validated according to the ICH guidelines. The method was also found to be robust. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification and solution stability. Keywords: RP-HPLC, Hydrocortisone, Acyclovir, Agilent , Mobile Phase, Retention time.

A new method was established simultaneous estimation of calcipotriene and dipropionate by RP-HPLC method. The chromatographic conditions were successfully developed for the separation of calcipotriene and dipropionate by using coloumn xterr C-18(4.6*250mm) 5µm, flow rate was 1.0ml/min mobile phase ratio Phosphate buffer (0.05M) pH 3.6: ACN (40:60%v/v) (pH was adjusted with ortho phosphoric acid), detection wave length 260nm.the instrument used was water HPLC auto sampler and PDA or detector. The analytical method was validated to ICH guidelines. The linearity range Dipropionate   and Calcipotriene were found to be from 100-500 µg/ml of Dipropionate and 1-5µg/ml of Calcipotriene. Linear regression coefficient was not more than 0.999.

A simple and effective RP-HPLC method had been developed for the estimation of vorinostat in capsule, using Apollo C18 (4.6 x 150mm, 5mm), mobile phase 100% methanol, detection wavelength at 247 nm, at flow rate of 1ml/min at retention time 3.43 min for vorinostat. Linearity was obtained in the range of 5µg/ml to 25µg/ml for vorinostat. The correlation coefficient was found to be 0.999. The Recovery studies were performed for vorinostat in the range of 50% - 150 %. The % Assay for vorinostat is 99.85 % .Forced Degradation studies were conducted according to the ICH guidelines and the Drug Product was found to be stable in all conditions. Hence, the method could be successfully applied for routine analysis of vorinostat capsules.

An isocratic reversed-phase liquid chromatograpic assay method was developed for the quantitative determination of Atorvastatin calcium (ATOR) and Clopidogrel bisulphate (CLOP) in combined dosage form. A Zodiac C18, 250x4.6mm, 5µm column and OPA Buffer: ACN (70: 30,v/v) as mobile phase. The flow rate was 1mL/min and effluents were monitored at 241 nm. The retention times of Atorvastatin and Clopidogrel were 5.8 min and 3.5 min respectively. The correlation coefficient was found to be 0.99947 (for ATOR) and 0.99944 (for CLOP). The proposed method was validated with respect to linearity, accuracy, precision, and robustness. The method was successfully applied to the estimation of Atorvastatin and Clopidogrel in combined capsule dosage form.

This paper describes the common analytical method suitable for the estimation of selected triptans (Naratriptan, Sumatriptan succinate, Zolmitriptan) by reversed phase high performance liquid chromatography (RP-HPLC). Chromatographic separations were conducted on Phenomenex Luna, C18 250 X 4.6 mm, 5 microns column at room temperature using 6.8 pH phosphate buffer: acetonitrile (60: 40) as a mobile phase at a flow rate of 1.0ml min-1, while UV detection was performed at 225nm. The retention time was found to be 3.130, 3.153, 2.143min respectively for the selected triptans. The method was found to be linear in the range of 2-10µg ml-1 for all the drugs. The proposed method is having good sensitivity due to low LOD and LOQ values. Analytical recovery was >99.3%. The method was validated statistically and applied for the quantitative analysis of triptans in bulk and formulations.

The simple, sensitive, reliable and economically new method was developed for the estimation of Ramipril (RAM) and Telmisartan (TEL) by RP-HPLC in combined dosage form. After several trials with the different combinations and ratios of solvents, the present chromatographic parameters were optimized. It was found that potassium dihydrogenphosphate (pH 3.0): methanol: acetonitrile (30:20:50 v/v/v) was given satisfactory results. A C18 column (Agilent ODS UG 5 column) having dimensions of 4.5mmx250mm was used. The mobile phase was pumped at a flow rate of 1.0ml/min and the eluents were monitored at 210nm. System suitability was carried out by injecting six replicate injections of 100% standard concentration, number of theoretical plates, HETP(height equivalent Theoretical plate) and resolution were satisfactory. The optimized chromatograms confirm the presence of Ramipril and Telmisartan at Rt: 4.1 min and Rt: 5.11min respectively without any interference. The concentration range of 1-5µg/ml for RAM and 8-40µg/ml for TEL were linear with correlation coefficients 0.999 and 0.989 respectively. The percent recovery studies were found to be 99.5-99.88% and 99.93-99.99% w/w for RAM and TEL respectively which indicate method was accurate. The proposed method was precise and reproducible with %RSD of 0.93 for Ramipril and 0.41 for Telmisartan, respectively. The limits of detection and limits of quantification were 0.10µg/ml and 0.25µg/ml for Ramipril 0.32µg/ml and 0.78µg/ml for Telmisartan, respectively. The method was found to be robust and ruggedness and was well suitable for the estimation of commercial formulations of selected combinations.

A rapid, specific reversed phase HPLC method has been developed for simultaneous determination of pantoprazole and levosulpridein their formulations. Chromatographic separation of these two pharmaceuticals was carried out on an Aligent,Zorbax column (250mmx4.6mm, particle size 5μm)with a 600:4000 (v/v/v) mixture of Potassium dihydrogen orthophosphate (pH-3.0; 0.01M)  buffer adjusted with Ortho phosphoric acid and methanol as mobile phase. The flow rate 1.0mL.min-¹ and the analytes are monitored at 230nm.The assay results were linear from 240-720μg/mL for pantoprazole(r ² >= 0.9999) and 450-1350μg/mL for levosulpride (r ² >= 0.9999), showed intra- and inter-day precision less than 2.0%, and accuracy of 100%.The LOD was 0.00321 and 0.000549μg.mL-¹ for pantoprazole and levosulpride respectively. Separation was complete in less than 5 min. Validation of the RP-HPLC method showed to be robust, precise, accurate and linear over the range of analysis.