Toroidal Coil Countercurrent Chromatography: A Fast Simple Alternative to Countercurrent Distribution Using Aqueous Two Phase Partition: Principles, Theory, and Apparatus

Abstract
The principles, theoretical basis and equipment for continuous two phase toroidal coil chromatography are described. Rat liver homogenates were subjected to analytical subcellular fractionation by toroidal coil chromatography in a phase mixture of 3.3% (w/w) dextran T500, 5.4% (w/w) poly(ethylene glycol) 6000, 10 mM sodium phosphate-phosphoric acid buffer, pH 7.4, in 0.26 M sucrose containing 0.05 mM Na2EDTA and 1 mM ethanol. The distribution of organelles, as reflected by their marker enzymes, was compared to that obtained by discrete counter-current partition in a 17 transfer apparatus. Toroidal coil chromatography showed enhanced resolution of certain organelles. In particular, almost complete separation of plasma membrane from endoplasmic reticulum was achieved and some resolution of plasma membrane from lysosomes was obtained. It is concluded that toroidal coil chromatography offers a potentially useful alternative approach to organelle separation techniques.