Development and Validation of a Stability-Indicating Chromatographic Method for the Determination of Indacaterol Maleate with Glycopyr-ronium Bromide in Mixture

Introduction: (COPD) Chronic Obstructive Pulmonary Disease is a partially reversible and treatable lung disease, characterized by progressive limitation of airflow. It is one of the main causes of mortality and morbidity worldwide. Methods: An easy, precise and selective reversed-phase liquid chromatographic method, with stability-indicating assay was established and validated for the determination of indacaterol maleate and glycopyrronium bromide in the mixture. In addition, a forced degradation study was performed for indacaterol maleate, comprised of hydrolysis by acid and base, degradation by oxidation and heat, and photo-degradation. Separation and forced degradation were done by isocratic elution using a reversed phase phenyl column and (methanol: phosphate buffer) at ratio (65:35, v/v) with 3.5 pH buffer as an eluent at 1 mL min(-1) as a flow rate. Quantitation was accomplished using a UV detector at 210 nm. Results: The method showed good separation of glycopyrronium bromide, indacaterol maleate and its degradation products. Accuracy, linearity, and precision were acceptable over 10-160 mu g mL(-1) and 10-80 mu g mL(-1) concentration range for indacaterol maleate and glycopyrronium bromide, respectively. Conclusion: The proposed method does not require any previously done separation steps, making it applicable for the analysis of the drugs under investigation in their pharmaceutically marketed preparations.