SIMULTANEOUS DETERMINATION OF GLIMEPIRIDE AND ATORVASTATIN IN HUMAN SERUM BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY: APPLICATION TO PHARMACOKINETIC STUDY

Abstract

A simple and sensitive high performance liquid chromatographic method for simultaneous quantification of glimepiride (GMP) and atorvastatin (ATN) in human serum was developed and validated. GMP, ATN, and internal standard (IS), pioglitazone (PG) were extracted into dichloromethane and methanol solvent system and separated using an isocratic mobile phase on an Inertsil C₁₈ column. The eluent was monitored by UV detector at 230 nm. The linearity range of proposed method was 1–1600 ng mL⁻¹ for each analyte. The retention times for GMP, ATN, and IS were found to be 9.8, 6.92, and 7.96 min, respectively. The intra-day and inter-day coefficient of variation and percentage error values of the assay method were less than 15% and mean recovery was more than 96, 93, and 95% for GMP, ATN, and IS, respectively, and the method was found to be precise, accurate, and specific. The method was successfully applied for pharmacokinetic study of GMP and ATN after oral administration to patients. The C_Max, T_Max, and AUC_0–12 of GMP and ATN were found to be 355.3 ng mL⁻¹, 3.1 hr, 2167.5 ng h mL^−l and 12.6 ng mL⁻¹, 2.6 hr, 80.8 ng h mL^−l, respectively.

Keywords:

• atorvastatin
• glimepiride
• human serum
• pharmacokinetics
• reversed phase high performance liquid chromatography
• simultaneous

ACKNOWLEDGMENTS

The authors thank Dr. Reddy's Laboratories, Hyderabad, India for providing gift samples of glimepiride, atorvastatin, and pioglitazone. The authors also thank Gandhi Hospital, Hyderabad, India for providing facilities to carry out the pharmacokinetic study.

Notes

^a Values are mean ± S.D (n = 3).

^b After 12 hr at room temperature.

^c After three freeze thaw cycles.

^d After 30 days at −20°C.