AbstractThe present communication describes the novel application of mixed-mode adsorbents for bifunctional chromatography. Oasis MCX mixed-mode adsorbent (Waters GmbH, Eschborn, Germany) shows a high binding capacity for Se-Met. The adsorbed selenoamino acid is easily eluted by pH change and addition of organic solvent. Determined adsorption isotherm parameters are suitable for its analytical and preparative chromatographic isolation. A chromatographic column packed with the Oasis MCX adsorbent, designed for a single use solid phase extraction, was successfully applied for bifunctional chromatographic separation of Se-Met from hydrolysed Antarctic krill samples with 85 ± 5% recovery. The MCX-packed column was used for more than 60 runs without any change in its performance.