Biotage has produced an application note describing the extraction of a panel of steroid hormones from human serum using ISOLUTE® SLE+ Supported Liquid Extraction plates prior to LC/MS-MS analysis.
The simple sample preparation procedure described in this application note delivers clean extracts and high, reproducible recoveries (>75%, RSD <10% ) for all analytes in human serum, with linearity >0.99 in the range 5–5000 pg/mL.
ISOLUTE SLE+ Supported Liquid Extraction plates offer an efficient alternative to traditional liquid-liquid extraction (LLE) for bioanalytical sample preparation, providing high analyte recoveries, no emulsion formation, and significantly reduced sample preparation.
For the sample prep procedure and both UHPLC and mass spectrometry conditions please download the application note.
If the polar metabolite DHEAS is to be included in the steroid suite, ethyl acetate should be used as the elution solvent. If DHEAS is not required, an alternative elution solvent, ethyl acetate: hexane (75:25, v/v) can be used.
The optimized ISOLUTE® SLE+ protocol using ethyl acetate demonstrated analyte recoveries greater than 75%. The optimized ISOLUTE SLE+ protocol using ethyl acetate:hexane (75:25, v/v) demonstrated analyte recoveries greater than 80% (except DHEAS). RSDs were below 10% for all analytes using both protocols.