The polysaccharide maltodextrin (MD) can provide a low cost alternative to substitute the fractioned dextran for the use with polyethylene glycol (PEG) in aqueous two-phase, two-polymers systems. Ln this work we have studied the partitioning of Bovine Serum Albumin (BSA), alpha-Lactoalbumin (alpha-La) and beta-Lactoglobulin (beta-Lg) in PEG/MD aqueous two-phase systems. The experiments were performed at local atmospheric pressure (727 mmHg) and 25 degrees C. The influence of the polymers molecular weights and tie-line length were investigated. (C) 2000 Elsevier Science Ltd. All rights reserved.423279282