A Validated Enantioselective Assay for the Determination of Ibuprofen in Human Plasma Using Ultra Performance Liquid Chromatography with Tandem Mass Spectrometry (UPLC-MS/MS)

András Szeitz,Kenneth Wayne Riggs,Bob Cheung,Henry Tao Peng,Andrea Nicole Edginton

doi:10.4236/ajac.2010.12007

Abstract

A modified ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantitation of ibuprofen enantiomers in human plasma. Ibuprofen and flurbiprofen (internal standard) were extracted from human plasma at acidic pH, using a single-step liquid-liquid extraction with methyl-tert-butyl ether. The enantiomers of ibuprofen and flurbiprofen were derivatized to yield the corresponding diastereomers. Chromatographic separation was achieved using a phenyl column with a run time of 20 min. (R)- and (S)-ibuprofen were quantitated at the multiple reaction monitoring (MRM) transition of m/z 360.2 ? 232.1, and (R)- and (S)-flurbiprofen were monitored at the MRM transition of m/z 398.3 ? 270.1. The method was validated for accuracy, precision, linearity, range, limit of quantitation (LOQ), limit of detection (LOD), selectivity, absolute recovery, matrix effect, dilution integrity, and evaluation of carry-over. Accuracy for (R)-ibuprofen ranged between –11.8% and 11.2%, and for (S)-ibuprofen between –8.6% and –0.3%. Precision for (R)-ibuprofen was ≤ 11.2%, and for (S)-ibuprofen ≤ 7.0%. The calibration curves were weighted (1/X2, n = 7) and were linear with r2 for (R)-ibuprofen ≥ 0.988 and for (S)-ibuprofen ≥ 0.990. The range of the method was 50 to 5000 ng/mL with the LOQ of 50 ng/mL, and LOD of 1 ng/mL, for (R)- and (S)-ibuprofen requiring 100 µL of sample. The method was applied successfully to a pharmacokinetic study with the administration of a single oral dose of ibuprofen capsules to human subjects.

Highlights

Ibuprofen, a member of the 2-substituted arylpropionic acid (2-APA) family, is a non-steroidal anti-inflammatory drug (NSAID), which is used to treat moderate pain, fever, rheumatic disorders and related inflammatory diseases
The method was validated for accuracy, precision, linearity, range, limit of quantitation (LOQ), limit of detection (LOD), selectivity, absolute recovery, matrix effect, dilution integrity, and evaluation of carry-over in human plasma using 100 μL of sample
Compared to previously published assays, sample preparation was simplified without the need of post-derivatization sample clean-up [29], sample volume required for analysis was reduced at least 5-fold [6,25,29], the range of the calibration curve was extended into the three-digit range [23,25,29], baseline separation of (R)- and (S)-ibuprofen was achieved [20,25] and the sensitivity was increased 2-fold [23,24,25,29]

Summary

Introduction

A member of the 2-substituted arylpropionic acid (2-APA) family, is a non-steroidal anti-inflammatory drug (NSAID), which is used to treat moderate pain, fever, rheumatic disorders and related inflammatory diseases. Ibuprofen undergoes chiral inversion in vitro [1] and in vivo, during metabolism in rats, mouse, rabbits [2,3,4]. Several methodologies are available for the determination of ibuprofen. These techniques include direct or indirect high performance liquid chromatography (HPLC) methods. In the direct HPLC methods, a chiral stationary phase is used and the enantiomers are analyzed without sample derivatization. Certain direct HPLC methods employ ultra-violet (UV) detection using α1-acid glycoprotein [16,17,18,19], β-cyclodextrin [20], cellulose [21], polysaccharide [22], and amylose derivative [23] chiral sta-

Objectives

Methods

Conclusion