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

Extraction conditions for optimal performance in liquid-phase microextraction (LPME) and other extraction techniques are often based on trial-and-error experiments. By investigating the molecular interactions taking place between the analyte and the extraction system, we can build models that help us predict when an analyte is optimally extracted. In the below paper we combine existing theory on extraction kinetics and system equilibrium together with empirical data to build the fundamentals for better prediction models. We introduce the terms slow kinetics, optimal extraction window (OEW), and membrane trapping as a tool to describe the state of the extraction system.