Abstracto

A stability-indicating RP-HPLC determination of eszopiclone in drug substance

Nilesh N.Kadam, Pratibha C.Patil

A simple, specific, accurate and stability-indicating reversed phase high performance liquid chromatographic method was developed for the determination of Eszopiclone in drug substance, using Inertsil ODS-3 column (250 mmLength x 4.6 mmID, 5 µ Particle Size) and isocratic mobile phase composed of buffer and acetonitrile in the 62:38 ratio, at a flow rate of 1.5 mL min-1 with UV detection at 303 nm. The Retention time of Impurity B, Impurity C, ImpurityAand Eszopiclone were found to be 3.867 min, 7.305 min, 18.729 min and 30.817 min respectively. The proposed method was validated as per ICH guidelines[1-2]. The Linearity for Eszopiclone was in the range of 50-150 µg mL-1. The recovery was found to be in the range of 100.4-101.3%. The detection limit and quantification limitwere found to be in the range of 0.1 µg mL-1 and 0.25µg mL-1 respectively. Eszopiclone was subjected to acid, alkali and neutral hydrolysis, chemical oxidation and dry environmental condition. The degraded product peaks were well resolved from the pure drug peak with significant difference in their retention time values. This proposed method was validated and successfully employed for quantitative analysis of Eszopiclone in drug substance.