Simultaneous determination of residual stilbenes and stilbene metabolites in animal tissue by liquid chromatography–tandem mass spectrometry

A liquid chromatographic (LC)–tandem mass spectrometry (MS/MS) method was developed for simultaneous determination of stilbenes, diethylstilbestrol (DES), hexestrol (HEX), and dienoestrol (DEN) in animal tissue. Sample clean-up and analyte enrichment was performed by automated solid-phase extraction (ASPE) with a silica gel cartridge. Detection capabilities (CCβ) related to the transition products of lowest abundance for the method were 0.04–0.45 ng g−1 in tissue and were achieved using atmospheric pressure chemical ionization (APCI) in negative mode. The use of an internal standard in combination with the simplified sample preparation led to a sensitive and reliable analytical method. The recovery level of the method was 84–108% for DES and DEN between 0.5 and 5 ng g−1, and 59–87% for HEX between 0.25 and 2.5 ng g−1.