ABSTRACT
Pharmaceuticals (active substances and/or their active metabolites) are traced in biological uids in order to study pharmacokinetics (PK), bioavailability (BA) aspects, and to assess the bioequivalence (BE) between different formulations. Over the last 15 years, analytical chemistry has played an increasingly important role in almost all steps of drug discovery and development. Biological uids of human or animal origin
(blood, plasma, urine, mucus, perspiration, saliva, synovial, etc.) have been intensively studied in order to estimate PK, BA, and BE of different drug formulations. The literature is already overwhelmed, and it is beyond the purpose of this chapter to mention all contributions to this topic. For this reason, this topic has been rarely reviewed, a rst attempt dating back to 1983 [1]. As a matter of fact, only a few major works have been cited here to complete the topic related to drug derivatization and its importance [2-4]. It is worth emphasizing here that the quality of data involved in a drug development strategy is highly related to the quality of the analytical processes used to assay target compounds in biological matrices. In pharmaceutics, analytical processes applied for drug assay are commonly based upon a highperformance liquid chromatographic (HPLC) technique. Proper sample preparation procedures should also be applied to achieve cleanup, isolation from the interfering matrices of the target compounds, and their concentration.
