Adsorption of proteins on solid surfaces is widely studied because of its importance in various biotechnological, medical, and technical applications, e.g., biosensor cardiovascular implants and chromatography. Adsorption thermodynamics has been studied on the microbeads of N,N'-diethylaminoethyl (DEAE) dextran anion exchanger for bovine serum albumin at 25, 30, 35 40, and 45 degrees C. As a result some thermodynamic parameters like Freundlich constants, thermodynamic equilibrium constant (K-D), standard free energy changes standard entropy changes (Delta S-assoc), and standard enthalpy change (Delta H-assoc) have been evaluated. Using the linear Van't Hoff plot, the Delta H-assoc value of the system for the interaction of BSA adsorbed crosslinked DEAE dextran microbeads was determined as 12.5 kj/mol. (c) 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 2300-2304, 2006