Optimized Analytical Methodology for Celecoxib and Paclitaxel Quantification in Plasma Using LC-MS/MS

Abstract

This study presents an advanced and highly specialized analytical method for quantifying Celecoxib and Paclitaxel in plasma samples using Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS). The method is optimized for precise and accurate measurement of both drugs at low concentrations (from parts per trillion to parts per million). The preparation of stock solutions, calibration standards, and internal standards (Paclitaxel as the internal standard) follows rigorous protocols to ensure consistency and minimize error. Special attention is given to the preparation of plasma samples, which are spiked with known concentrations of Celecoxib to generate accurate calibration curves. The method validation follows ICH M10 guidelines and evaluates specificity, linearity, accuracy, precision, and sensitivity. Results demonstrate high specificity with minimal interference from placebo samples, as shown by detailed chromatographic data. The calibration curve is linear over a wide range, with weighted linear regression applied to improve accuracy. The robustness of the method is further validated through multiple testing phases, with results confirming the method’s ability to maintain high performance across different sample types and conditions. The application of this method in clinical studies is discussed, particularly in the context of drug monitoring and pharmacokinetic studies, with emphasis on the use of internal standards to mitigate matrix effects. The validation results highlight the method’s potential for routine clinical application in both residential and commercial laboratories, providing a reliable tool for assessing drug levels in plasma and ensuring patient safety in therapeutic settings.