Comparison of sample preparation options for the extraction of a panel of endogenous steroids from serum prior to UHPLC-MS/MS analysis

The supported liquid extraction (SLE) process is analogous to traditional liquid-liquid extraction (LLE) and utilizes the same water immiscible solvent systems for analyte extraction. Instead of shaking the two immiscible phases together, in SLE, the aqueous sample is immobilised on an inert support and the organic phase flows through the support, eliminating problems such as emulsion formation and low analyte recoveries.

This poster compares sample preparation options for the extraction of a panel of endogenous steroids from serum. LC-MS/MS parameters were investigated for increased sensitivity: MRM transitions, chromatography and mobile phase additives for use with positive and negative ionisation modes. Particular emphasis was placed on the sample preparation to provide high reproducible recoveries whilst minimizing matrix effects and co-extracted materials such as proteins and phospholipids. Solid phase extraction was compared to supported liquid extraction in terms of recoveries, ion suppression, phospholipid content, calibration curve performance and overall sensitivity.