A Rapid, Rugged and Sensitive Bioanalytical Method for the Determining of Meloxicam in Human Plasma by LC-MS-MS
Authors
W. Edgemond, M. Sullivan, C. Buggé
Purpose
Meloxicam is a member of the enolic acid group of nonsteroidal anti-inflammatory drugs (NSAIDs). Meloxicam is a cyclooxygenase-2 (COX-2) inhibitor used in the treatment of osteoarthritis. We present a method for measuring meloxicam in EDTA human plasma by LC-MS-MS.
Methods
Human EDTA plasma containing meloxicam and the internal standard piroxicam was validated over a range of 50.0 to 3000 ng/mL based on the analysis of 0.100 mL of human plasma. Plasma was treated with potassium phosphate (1.0 M, pH 7.0) and extracted with ethyl acetate/cyclohexane, 9:1. The organic layer was transferred, evaporated, reconstituted, and injected onto a YMC Cyano, 50 x 4.6 mm HPLC column connected to a Sciex API 3000 LC-MS-MS in positive ion ESI mode. The mobile phase was water/acetonitrile/formic acid, 50:50:0.1 pumped at 1.0 mL/min. with 20% of the flow split to the MS. The precursor/product ions (m/z 352/115) were monitored in MRM mode with a run time of approximately 1.5 minutes.
Results
No matrix interference was observed across the elution windows of the analytes. Ruggedness of the assay was tested with quality control (QC) samples analyzed over three days. The overall precision (%CV) of replicate QC samples was better than 6.1% for the QC pools (n=18 at each level). The precision for three days at the lowest limit of quantitation (LLOQ) was 6.6% (n=18). The intrarun CV ranged from 2.7% to 9.3% (n=6 each day). The mean (n=3) correlation coefficient was 0.9965, showing acceptable linearity over the 50.0 to 3000 ng/mL range. Average extraction recovery was approximately 74%. Meloxicam was shown to be stable in plasma during normal sample handling.
Conclusions
These data demonstrate a rapid, rugged and sensitive method for quantitating meloxicam in human plasma. Analysis for a large number of samples can be processed quickly using the Multiprobe robotics platform.