The polymeric reversed micelles were formed with polyoxyalkylene block copolymers as surfactant and 1-octanol as co-solvent in the polyoxyalkylene block copolymers/1-octanol/p-xylene system. The polyoxyalkylene block copolymers consist of hydrophilic poly(ethylene oxide) (PEO) and hydrophobic poly(propylene oxide) (PPO). Two types of copolymers, PEO-PPO-PEO-type and PPO-PEO-PPO-type triblock copolymers were used. Our present interests are focused on the formation of the reversed polymeric micelles and subsequently separation of amino acids by the polymeric reversed micelle solutions. Extraction equilibrium partition of amino acids between polymeric reversed micelle solutions and water was investigated to study the extraction behaviours. The copolymer type and aqueous phase pH. affected the extraction process. A model for solute solubilisation by the polymeric reversed micelles is proposed. (C) 2003 Elsevier B.V. All rights reserved.