Motströmskromatografi

Motströmskromatografi, also known as countercurrent chromatography (CCC) or countercurrent liquid chromatography (CCLC), is a liquid-liquid separation technique that relies on the unequal partitioning of analytes between two immiscible liquid phases. Unlike traditional column chromatography, CCC does not use a solid stationary phase. Instead, one of the liquid phases is retained within the separation column through mechanical means, while the other liquid phase acts as the mobile phase and flows through it.

The separation process in CCC is based on the principle of differential partitioning. As the mobile phase moves through the stationary liquid phase, components of the sample distribute themselves between the two phases according to their relative solubilities. Components that are more soluble in the stationary phase will spend more time associated with it and elute later, while those more soluble in the mobile phase will move faster and elute earlier.

CCC offers several advantages, including the absence of irreversible adsorption of analytes to a solid support, which can be crucial for separating sensitive biomolecules. It also allows for high sample loading capacities and can be scaled up for preparative separations. The choice of solvent system is critical for achieving effective separation and is typically determined through preliminary equilibrium studies. Various configurations of CCC exist, such as centrifugal partition chromatography (CPC) and high-speed countercurrent chromatography (HSCCC), which employ different mechanical designs to enhance separation efficiency and speed.