Development and Validation of UV-Spectrophotometric and RP-HPLC Methods for the Determination of Eszopiclone in Bulk Drug and Tablet Dosage Forms

Abstract

A simple, accurate, precise, and economical UV-spectrophotometric method and a rapid reverse-phase high-performance liquid chromatographic (RP-HPLC) method were developed and validated for the determination of Eszopiclone in bulk drug and tablet dosage forms. In the UV method, Eszopiclone exhibited maximum absorbance at 305 nm using 50% v/v methanol as solvent. Beer’s law was obeyed in the concentration range of 4–32 μg/mL with a correlation coefficient of 0.999. The RP-HPLC method was developed using a Phenomenex Gemini C18 column (250 × 4.6 mm, 5 μm) with methanol:water (80:20, v/v) as mobile phase at a flow rate of 1.0 mL/min and detection at 305 nm. The retention time of Eszopiclone was found to be 5.38 min. Both methods were validated according to ICH guidelines with respect to linearity, accuracy, precision, ruggedness, robustness, specificity, LOD, and LOQ. The percentage recovery ranged between 99.54–100.24%, indicating good accuracy. The proposed methods were successfully applied for routine analysis of Eszopiclone in bulk drug and tablet formulations.