Interactions of bovine serum albumin with humic acid-Cu(II) aggregates in poly(hydroxyethylmethacrylate) cryogel column

Understanding the interactions of proteins with humic acid in different media is essential for many applications. This paper investigates the interactions of bovine serum albumin with humic acid-Cu(II) complexes in a poly(hydroxyethylmethacrylate) cryogel column. Humic aggregates were immobilized within the cryogenic matrix. Protein sorption studies were conducted at different temperature, ionic strength, protein concentration, pH and flow-rate. Protein adsorption increased at lower pHs (close to the isoelectric point of the protein; 4.7) and higher temperatures but decreased at higher ionic strength and flow-rates. Both electrostatic and hydrophobic interactions played roles in the sorptive behavior of the protein molecules. Isotherm analysis showed the monolayer protein adsorption onto humic molecules immobilized column.