[Progress in mass spectrometric analysis of steroid conjugates--LC/MS and MS/MS]

For the last decade, mass spectrometric methods for analysis of low volatile and/or thermounstable biological components have been remarkably advanced in the field of life sciences. Such progress has been mainly achieved along with the development of soft ionization techniques. High-performance liquid chromatography/mass spectrometry (LC/MS) and tandem mass spectrometry (MS/MS) are often used for analysis of steroid conjugates without prior deconjugation since gas chromatography/mass spectrometry is not suitable for their direct determination owing to low volatility and thermounstability. These combination techniques using a mass spectrometer with liquid chromatography or another mass spectrometer are powerful and promising tools for analysis of intact steroid conjugates in biological matrix. In this paper, the recent progress in their applications has been reviewed.