Quartz-crystal microbalance and cyclic voltammetric studies of the adsorption behaviour of serum albumin on self-assembled thiol monolayers possessing different hydrophobicity and polarity

Abstract

The adsorption behaviour of bovine serum albumin (BSA) on the surface of four different types of thiol monolayer was studied using a quartz-crystal microbalance (QCM) and cyclic voltammetry (CV). BSA was bound to the thiol monolayers with different efficiencies, depending on their surface properties. BSA was adsorbed more efficiently to hydrophobic thiol monolayers than to hydrophilic thiol monolayers. The electrostatic force of attraction or repulsion between the BSA molecules and the monolayer surface did not play a primary role in determining the adsorption behaviour of BSA. The binding of BSA was highly accelerated around its isoelectric point (pH 5.0).