Investigation of protein-polyelectrolyte complex and conjugates by high performance liquid chromatography methods

Objective: Intermolecular complex by electrostatic interaction and specifically coupled conjugates between bovine serum albumin and poly (N-Vinyl-2-pyrrolidone-co-acrylic acid) were investigated as an intermolecular model system due to their importance in biotechnology and medicine. Material and Method: In this study, water soluble protein-polyelectrolyte complexes and bioconjugates at different molar ratios were characterized by using high performance liquid chromatography. Results and Conclusion: It was observed that the complex formation depends on the molar ratio of molecules and pH of the solutions. When bovine serum albumin and poly (N-Vinyl-2-pyrrolidone-co-acrylic acid) are oppositely charged [pH <= pI (isoelectric pH)] two macromolecules associate through electrostatic interactions. There is no interaction and stable complex formation between these molecules at higher pH levels. Therefore these molecules bound covalently to each other by using cross linkers when pH levels higher than the pI of the protein. High Performance Liquid Chromatography analysis showed that the amount of protein-polymer complex is increased by the increase in molar ratio of polymer, and the amount of free bovine serum albumin is decreased.