Development and Validation of a Stability-Indicating RP-HPLC Method for Simultaneous Estimation of Olanzapine and Samidorphan in Bulk and Pharmaceutical Dosage Form

Abstract

Abstract
Objective: The aim of the study was to develop and validate a stability indicating RP-HPLC Method for simultaneous estimation of Olanzapine and Samidorphan in bulk and formulation.
Materials and Methods: The chromatographic separation was achieved on Agilent C18 columns (4.6 × 150 mm, 5 µm) using a mixture of acetonitrile and 0.01% orthophosphoric acid in a ratio of 70:30 (v/v) as mobile phase. The flow rate was set at 1.0 mL/min and detection was performed at 268 nm. Retention time of Olanzapine and Samidorphan was found to be 2.211 min and 2.772 min respectively.
Results: The method was validated as per ICH Q2B. Linearity was observed in the range 5–30 µg/mL for Olanzapine and 2.5–15 µg/mL for Samidorphan (R² = 0.999). Average % recovery was found to be 99.83% for Olanzapine and 99.53% for Samidorphan. The %RSD of intra and interday precision studies were found to be < 0.5%. LOD and LOQ values were found to be 0.27 µg/mL and 0.82 µg/mL for Olanzapine, 0.08 µg/mL and 0.24 µg/mL for Samidorphan, respectively. Forced degradation studies under different stress conditions reveal that the method is stability indicating.
Conclusion: The developed and validated rapid, simple, sensitive and specific RP-HPLC method will be useful for routine quality control analysis and stability study of Olanzapine and Samidorphan in bulk drug and marketed formulations.