Therapeutic drug monitoring is an interdisciplinary effort to improve patient's therapy
in terms of efficacy, adverse effects, drug-drug interactions or compliance. The accurate,
precise and timely determination of the drug concentration is central part of this
process. Quantitation in plasma is nowadays performed predominantly using liquid chromatography
hyphenated to tandem mass spectrometry (LC-MS/MS). The introduction of LC-MS/MS in
clinical laboratories started in the 1990 s. The reason for its fast growing success
is the combination of high sensitivity (ng/L to mg/L) and selectivity, dynamic range,
and the hyphenation to liquid chromatography systems. Sample preparation can often
be reduced to simple protein precipitation and dilution including suitable stable
isotopically labeled standards.
The aim of this presentation is to provide an insight into the analytical technique
and the processes involved in laboratory routine to determine the drug concentration
in plasma.
