AFM Study of Temperature and pH Effects on BSA Structure and Adhesion

With the wide application of biomacromolecular materials such as proteins, it is increasingly important to explore the influence of external environment on protein structure and properties. In this paper, the effects of temperature and pH on the structure and adhesion of bovine serum albumin (BSA) were studied by atomic force microscopy (AFM). The experimental results showed that the spatial structure of protein changed gradually with the increase of temperature, which was manifested by a decrease in the height of the protein molecule. The diversification of BSA adhesion with temperature was measured. And the adhesion between BSA and silicon tips decreased when the temperature increased. By varying the pH of the environment, it was found that the protein molecule height reduced under strong acidic or alkaline conditions, accompanied by the decrease of protein adhesion. Temperature and pH are revealed to be effective factors in transforming the structure of the protein, besides affecting the mechanical properties of the protein.