ABSTRACT
Metabolism studies play an important role in drug discovery and development. The advent of combinatorial drug synthesis has increased the need for a fast assessment of drug metabolism [1]. LC–MS is an important tool in the identification of drug metabolites [2-4]. The soft ionization conditions in electrospray ionization (ESI) or atmospheric-pressure chemical ionization (APCI) facilitate the detection of metabolism in biological samples. Many common biotransformation, e.g., oxidation, hydroxylation, hydrolysis, and reduction, can be detected from just the knowledge of the molecular mass of the metabolites. Further confirmation and/or structure elucidation of metabolites is possible using the variety of MS–MS platforms.
