Influence of salt and temperature on the interaction of bovine serum albumin with cetylpyridinium chloride: Insights from experimental and molecular dynamics simulation

Interaction of biopolymer bovine serum albumin (BSA) with a cationic surfactant cetylpyridinium chloride (CPC) has been performed using the conductometric technique in water as well as in the presence of electrolytes at various temperatures. The three critical micelle concentrations (c(1)*, c(2)*, and c(3)*) were achieved in case of pure CPC as well as CPC + BSA mixtures in all cases. The change of e values of CPC due to the addition of BSA reveal the interaction between BSA and CPC. The reduction of c* values in salts solution indicates that addition of salt favors the micellization of CPC + BSA mixed system as compared to that in aqueous solution. The Delta G(m)(0), values are obtained to be negative in all the cases. The Delta H-m(0) and Delta S-m(0) values reveal that the interactions between BSA and CPC are mainly hydrophobic and electrostatic origin. The thermodynamic properties of transfer were also evaluated as well as discussed in detail for the studied system. Molecular dynamics simulation disclosed how a protein interacts with surfactant molecules in presence of salt and no-salt environments. Although salt environment not only promotes the interaction between protein and surfactant, the overall collision cross-section of the protein remains almost unchanged. (C) 2018 Elsevier B.V. All rights reserved.