Development and Validation of Liquid Chromatography-Tandem Mass Spectrometry Method for the Quantification of Ertapenem in Human Serum

Abstract

We have developed and validated a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the quantification of ertapenem in serum samples derived from patients with complicated urinary tract infections. Ertapenem was separated on reverse phase C18 column within the analytical runtime of 2 min. Detection and quantification of ertapenem was based on multiple reactions monitoring under positive ionization mode using deuterium-labeled internal standard. The lower limit of quantification of ertapenem in serum was 1 μg/ml. Excellent linearity was demonstrated between 1–200 μg/ml in serum with r2>0.996. Accuracy and precision for the assay in serum were in the range of 96.7–106.5% and 0.59–4.22%, respectively. The developed method is specific with no endogenous co-eluting peaks in serum. Minimal matrix effect was found in serum between 94.9–107.3%. Ertapenem in serum was found stable at room temperature (25°C) of up to 4 h, in the autosampler (6°C) of up to 20 h and at least three freeze-thaw cycles with recovered concentration of more than 97.1%. This LC-MS/MS method is rapid, simple and provides sufficient sensitivity in measuring ertapenem concentration in serum samples derived from patients.