Analysis of the interaction mechanisms of polysaccharide homologs binding with serum albumin using capillary electrophorsis

Different polysaccharide homologs (as the ligand) binding to serum albumin (bovine serum albumin (BSA)) as the receptor were investigated by capillary electrophoresis (CE). The Hummel–Dreyer method (HD), frontal analysis method(FA), and vacant peak method(VP) were used to measure the interaction parameters of the polysaccharide-BSA system. A workable CE method was selected by comparing different analytical methods and a feasible binding model was established by evaluating the different theoretical equations. The binding mechanism of polysaccharide-BSA was also explored under physiological conditions. The results showed that both HD and FA method can be used to analyze the polysaccharide-BSA system, with the most suitable CE method being the HD, and the double logarithmic equation gives the best fit to the data. The binding parameters indicate that the interaction between polysaccharides and BSA had moderate affinity, which had only one type of binding site. This work provides a reference for future studies of polysaccharide-protein interactions. (author)