HPLC Analysis of Plasma Glipizide and its Application to Pharmacokinetic Study

Abstract

Glipizide is an oral hypoglycemic agent widely used to treat type 2 diabetes mellitus. In this study, an efficient HPLC-UV assay method for determining the plasma glipizide level was developed, validated, and used to assess the pharmacokinetic profile of the glipizide in healthy Korean volunteers. After extraction with diethyl ether, the chromatographic separation of glipizide was carried out using a Bondclone C₁₈ column (10 µm, 300 × 3.9 mm) with a mobile phase of 10 mM potassium phosphate monobasic and methanol (40:60 [vol/vol], pH 3.5) and UV detection at 225 nm. The flow rate of the mobile phase was 1.0 mL/min and the retention time of glipizide and internal standard (I.S.) was approximately 11.5 and 8.6 minutes, respectively. The quantification limit was 15 ng/mL and the linear range of the calibration curve ranged from 15 to 800 ng/mL in plasma with a correlation coefficient >0.9999. The mean accuracy was 86–101%. The coefficient of variation (precision) in the intra- and inter-day validation was 1.8–14.2 and 1.7–8.1%, respectively. The pharmacokinetics of oral glipizide was evaluated after administering 5 mg to each of 13 healthy Korean subjects. The AUC_inf, C_max, T_max, and T_1/2 were 3432 ± 886 ng·h/mL, 629.0 ± 94.2 ng/mL, 2.8 ± 1.8 h, and 3.9 ± 0.9 h, respectively. The results showed large inter-individual differences in the AUC_inf, C_max and T_1/2.

Keywords:

• Glipizide
• HPLC
• Pharmacokinetics

ACKNOWLEDGMENT

This study was supported by the 2007 Research fund of Korea Food and Drug Administration.

Manuscript 6449

Notes

^a healthy subjects.

^b NIDDM(non-insulin-dependent diabetes mellitus) patients.