Liquid chromatography-tandem mass spectrometry--application in the clinical laboratory

This review provides a concise survey of liquid chromatography-tandem mass spectrometry (LC-TMS) as an emerging technology in clinical chemistry. The combination of two mass spectrometers with an interposed collision cell characterizes LC-TMS as an analytical technology on its own and not just as a more specific detector for HPLC compared with conventional techniques. In LC-TMS, liquid chromatography is rather used for sample preparation but not for complete resolution of compounds of interest. The instrument technology of LC-TMS is complex and comparatively expensive; however, in routine use, methods are far more rugged compared to conventional chromatographic techniques and enable high-throughput analyses with very limited manual handling steps. Moreover, compared to both gas chromatography-mass spectrometry (GC-MS) and conventional HPLC techniques, LC-TMS is substantially more versatile with respect to the spectrum of analyzable compounds. For these reasons it is likely that LC-TMS will gain far more widespread use in the clinical laboratory than HPLC and GC-MS ever did. In this article, the key features of LC-TMS are described, method development is explained, typical fields of application are discussed, and personal experiences are related.