Determination of antituberculosis drug concentration in human plasma by MALDI-TOF/TOF.

Therapeutic drug monitoring allows to determine the best dosage regimen adapted to each patient optimizing the therapeutic benefits, while minimizing the risk for side effects. Here, the first methodological approach based on matrix-assisted laser desorption/ionization source equipped with tandem time-of-flight (MALDI-TOF/TOF) mass spectrometry for the determination of the antituberculosis (anti-TB) drugs ethambutol, pyrazinamide, rifampicin, and streptomycin concentration in the plasma of tuberculosis-infected patients is reported. The volume of the plasma sample was 200 microL.