title: Enantiomeric separation of S-zopiclone and its R-enantiomer in bulk drug samples by validated chiral RP-HPLC.
abstract: A simple and selective isocratic chiral RP-HPLC method was developed for the enantiomeric purity determination of S-zopiclone and the quantitative determination of R-zopiclone in bulk drug samples. Enantiomeric separation was achieved using Chiralcel OD-RH 150 x 4.6 mm, 5 microm particle size column at 25 degrees C using a mobile phase of 10 mM ammonium acetate and acetonitrile in ratio of 60:40 (v/v) as mobile phase at a flow rate of 1.0 mL x min(-1) and UV detection at 306 nm. The method resolves the R-zopiclone and S-zopiclone with resolution (Rs) greater than 1.6. The limit of detection (LOD) and limit of quantitation (LOQ) of the R-enantiomer were 0.12 microg x mL(-1) and 0.40 microg x mL(-1) respectively, for 10 microL injection volume. The percentage RSD of the peak area of six replicate injections of R-zopiclone at LOQ concentration was 4.6. The percentage recoveries of R-enantiomer from S-zopiclone were ranged from 97.3 to 99.8. Developed method was found to be selective in presence potential impurities. The developed chiral RP-HPLC method was validated with respect to precision, linearity, accuracy, robustness and ruggedness. The test solution and mobile phase was found to be stable up to 24 h after preparation.
authors.affiliation: Analytical Research, Custom Pharmaceutical Services, Dr. Reddy's Laboratories Ltd., Visakhapatnam, India.
authors.forename: S
authors.initials: S
authors.lastname: Sangaraju
authors.forename: M
authors.initials: M
authors.lastname: Lakshmi Kanth
authors.forename: B M
authors.initials: BM
authors.lastname: Rao
authors.forename: N
authors.initials: N
authors.lastname: Someswararao
mesh_terms: D053961:Azabicyclo Compounds / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D007202:Indicators and Reagents; D010879:Piperazines / Q000737:chemistry / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012996:Solutions; D013237:Stereoisomerism
chemical_list: D053961:Azabicyclo Compounds; D007202:Indicators and Reagents; D010879:Piperazines; D012996:Solutions; C515050:zopiclone