Stability-indicating method.

A simple, precise, accurate and stability-indicating reverse phase high performance liquid chromatography (RP-HPLC) method is developed for estimation of Levosalbutamol sulphate and Ipratropium Bromide in bulk and nebulizer dosage form. The method employed, with reverse phase Inertsil® 5μ C18 (250 × 4.0 mm) column in an isocratic mode, with mobile phase of acetonitrile: buffer in the ratio 77:23 (%v/v). The flow rate was 1.3 ml/min and effluent was monitored at 210 nm. Retention time was found to be 3.05 min., and 10.59 min. The method was validated in terms of linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ) etc. in accordance with ICH guidelines. Linear regression analysis data for the calibration plot showed that there was good linear relationship between response and concentration in the range of 25 – 150% of the working concentration (r2 > 0.999) respectively. The LOD and LOQ values for were found to be0.72,0.43, 1.24and 0.97 and μg/ml respectively. No chromatographic interference from placebo and degradants were found. The proposed method was successfully used for estimation of Levosalbutamol sulphate and Ipratropium bromide in bulk and nebulizer dosage forms.

A simple, precise, accurate and stability-indicating reverse phase high performance liquid chromatography (RP-HPLC) method is developed for estimation of Levosalbutamol sulphate and Budesonide in bulk and suspension for inhalation dosage form. The method employed, with reverse phase Inertsil® 5μ C18 (250 × 4.0 mm) column in an isocratic mode, with mobile phase of acetonitrile: buffer in the ratio 40:60 (%v/v). The flow rate was 0.8 ml/min and effluent was monitored at 266 nm. Retention time was found to be 3.16 min., 17.94 min. and 20.90 min. The method was validated in terms of linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ) etc. in accordance with ICH guidelines. Linear regression analysis data for the calibration plot showed that there was good linear relationship between response and concentration in the range of 25 – 150% of the working concentration (r2 > 0.999) respectively. The LOD and LOQ values for were found to be 0.43, 0.72, 0.97 and 1.24 µg/ml respectively. No chromatographic interference from placebo and degradants were found. The proposed method was successfully used for estimation of Levosalbutamol sulphate and Budesonide in bulk and suspension for inhalation dosage forms.

A simple, precise, accurate and stability-indicating reverse phase high performance liquid chromatography (RP-HPLC) method is developed for estimation of Isosorbide 5-Mononitrate in bulk drug and tablet dosage form. The method employed, with reverse phase phenomenex® Luna 5µ C18 (2) 100A (250 × 4.60 mm) column in an isocratic mode, with mobile phase of methanol: water: acetonitrile in the ratio 55:28:17 (%v/v/v). The flow rate was 1.0 ml/min and effluent was monitored at 217 nm. Retention time was found to be 4.391±0.015 min. The method was validated in terms of linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ) etc. in accordance with ICH guidelines. Linear regression analysis data for the calibration plot showed that there was good linear relationship between response and concentration in the range of 1- 9 µg/ml respectively. The LOD and LOQ values for were found to be 2.5 and 10 ng/ml respectively. No chromatographic interference from tablet excipients and degradants were found. The proposed method was successfully used for estimation of Isosorbide 5-Mononitrate in tablet dosage form.