ABSTRACT
Mass spectrometry-based bioanalytical methods play an important role in the entire process of searching new medicines to improve the quality of human life. High-performance liquid chromatography coupled to a tandem mass spectrometer (HPLC-MS/MS) has become the standard tool for the determination of pharmaceuticals in various in vitro and in vivo samples stemming from drug discovery and development experiments [1-5]. However, the major disadvantage of the HPLC-MS/ MS technique is that it does not readily provide information on the distribution of the administrated drug and its metabolites.
