BSA‐Polysaccharide Interactions at Negatively Charged Electrode Surface. Effects of Current Density

Constant current chronopotentiometric stripping (CPS) peak H due to catalytic hydrogen evolution reaction on Hg-containing electrodes appeared useful in the analysis of protein complexes with single-stranded and double-stranded DNA as well as with peptides. In dependence on stripping current (I-str), structural transition of the protein alone or in complexes can be followed as a result of the protein exposure to electric field effects. For the first time we show here that the CPS analysis can be used for the study of the interaction of BSA with a polysaccharide namely sodium alginate (SA). BSA-SA complex formation was accompanied by the shift of the structural transition of BSA to lower -I-str intensities. Another polysaccharide dextran did not alter I-str-dependent structural transition of BSA. BSA-SA complex can be disturbed by an electric field effect or high ionic strength confirming the electrostatic nature of BSA-SA interaction.