Introduction
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the
most widely used therapeutic agents [1], being diclofenac, ibuprofen
and naproxen the most frequently administered. Taken singly
or in combination with other classes of drugs, they relieve symptoms
across multiple clinical indications, including short and long
term pain states and a range of musculoskeletal disorders [2]. In the
last years, the analysis of NSAIDs has gained an increased attention
in the scientific literature, probably related to the long-term side
effects of those compounds. Acute overdose or chronic abuse of
NSAIDs can cause gastrointestinal [3] and cardiovascular complications
[4]. So, NSAIDs residues in prescribed individuals, using urine,
plasma or blood as biological matrices have been monitored [5,6].
On the other hand, the occurrence of NSAIDs in the environment
has drawn significant consideration because they are not efficiently
eliminated in sewage treatment plants and then, they are released
into the surface water. In this scenario, it is easy to understand the
need of sensitive and selective analytical procedures for the deter-mination of NSAID residues, both, in biological and environmental
samples.