Development of an HPLC–MS/MS Method for the Determination of Ceftolozane/Tazobactam in Bronchoalveolar Lavage Fluid

Aim: We describe the validation of an HPLC–MS/MS method to analyze ceftolozane and tazobactam simultaneously in saline matrixes. Materials & methods: An Agilent 1260 HPLC interfaced to an Agilent 6470 triple-quadrupole mass spectrometer was used for quantification. A reverse-phase column running a gradient of water and acetonitrile containing 0.1% formic acid mobile phase at a flow rate of 1.0 ml/min provided chromatographic fractionation. Tazobactam 15 N 3 was used as the internal standard. The standard curves were linear over a range of 0.02–0.5 μg/ml. Conclusion: This methodology represents a simple, reproducible approach to the determination of drug concentrations with accuracy and precision for pharmacokinetic studies undertaken with this recently US FDA-approved antimicrobial therapy.