Recent Advances on Liquid Chromatographic and Mass Spectrometric Analysis of Selective Estrogen Receptor Modulators (SERMs) in Biological Fluids

Selective Estrogen Receptor Modulators (SERMs) comprise a class of therapeutic agents widely prescribed for the prevention and treatment of breast cancer, osteoporosis and postmenopausal symptoms. SERMs are exemplified by Tamoxifen (TAM), a molecule displaying pronounced activity that is mediated through its in vivo active metabolites (Z)- 4-hydroxytamoxifen and endoxifen. The extensive in vivo metabolism of SERMs along with their wide use as medications, has led to the development of specific methods for the efficient separation and accurate identification of their parent molecules and metabolites in biological fluids. For this purpose, Liquid Chromatography (LC) is considered the most efficient separation technique, especially when combined with mass spectrometry in simple (LC-MS) and/or tandem mode (LC-MS/MS), constituting the cutting edge analytical approach in terms of selectivity and sensitivity. This review intends to account the major recent advances on the LC-MS determination of SERMs and metabolites in biological fluids, a subject not reviewed to date with the exception of TAM which was extensively reviewed on 2010, consequencing the inclusion of only very recent reports on TAM assessments.