Ceftriaxone pharmacokinetics by a sensitive and simple LC-MS/MS method: Development and application

Ceftriaxone is a third-generation cephalosporin, worldwide use as a first-line treatment for several infections, including life-threatening infections as meningitis or endocarditis. Nowadays, ceftriaxone use is changing, embracing high-dose schemes, new populations treated and requirement of dose individualization and optimization. These reasons warranted the development of new sensitive assays. This study aimed to develop and validate a fast and handy bioanalytical method for the quantification of ceftriaxone in human plasma covering a broad range of concentrations. The analysis was performed using high-performance liquid chromatography coupled to tandem mass spectrometry. Sample preparation was based on protein precipitation with acetonitrile followed by centrifugation. Chromatography separation was performed on Phenomenex Luna C18 column (5 μm, 150 × 2.0 mm) and a mobile phase consisting of 70 % of mobile phase A (10 mM of ammonium acetate and 1% formic acid in purified water) and 30 % mobile phase B (0.1 % formic acid in acetonitrile) at a flow rate of 500 μl/min on an isocratic program. Both the analyte and the internal standard were quantified using the positive electrospray ionization (ESI) mode within a single runtime of 5.00 min. The method was validated following the U.S. Food and Drug Administration guidelines over the concentration range of 3-1000 μg/mL. The within-run and between-run precision and accuracy were <15 %, and therefore met the standard regulatory acceptance criterion. In conclusion, a sensitive and robust LC-MS/MS method was developed for a fast quantitation of ceftriaxone concentrations in plasma samples with multiples applications in research and clinical therapeutic drug monitoring.