A simple and selective liquid chromatography- tandem mass spectrometry method for determination of ε-aminocaproic acid in human plasma

Understanding the clinical pharmacology of the antifibrinolytic drug epsilon-aminocaproic acid (EACA) is critical for rational drug administration in children. The aim of this study is to develop a reliable assay for the determination of EACA in human plasma. We describe a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) assay for EACA in human plasma. Sample preparation involved plasma dilution (1:2040), followed by reversed-phase chro- matographic separation and selective detection using tandem mass spectrometry. EACA had a linear range of 1 - 250 µg/mL. The intraday precision based on the standard deviation of replicates of quality control samples ranged from 4.7 to 10.4% and the accuracy ranged from 92-106%. The interday precision ranged from 4.6 to 9.8% and the accuracy ranged from 95-103%. Stability stud- ies showed that EACA was stable during the conditions for sample preparation and storage. The described method is robust and successfully employed for clinical studies of EACA in children.