Membrane-based liquid-phase microextraction of basic pharmaceuticals – A study on the optimal extraction window

The present paper defines the optimal extraction window (OEW) for three-phase membrane-based liquidphase microextraction (MP-LPME) in terms of analyte polarity (log P), and anchors this to existing theories for equilibrium partitioning and kinetics. Using deep eutectic solvents (DES) as supported liquid membranes (SLM), we investigated how the OEW was affected by ionic-, hydrogen bond and π-π interactions between the SLM and analyte.