Interfacial and Thermodynamic Approach of Surfactants with α-Chymotrypsin and Trypsin: A Comparative Study

Abstract

The conductivity as well as surface tension measurements have carried out to study the interactions among cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulpahe (SDS) with α-chymotrypsin (α-CT) and trypsin in aqueous medium on pH 7.75. The surface parameter i.e., critical micelle concentrations (CMC), the maximum surface excess concentration (Γ_max), minimum area per surfactant molecule (A_min) and the surface pressure at CMC (π_cmc), and thermodynamic parameters i.e., degree of ionization (α), Gibbs free energy of micellization (ΔG°_m), the standard Gibbs energy of adsorption (ΔG°_ads)_, the free energy at air-water interface (ΔG^s_mim) have been evaluated using surface tension and conductivity measurement. Thermodynamic parameters indicate that enzyme-CTAB/SDS monomeric aggregation started to form micelles at a higher concentration of surfactant to compare with the CMC of pure CTAB/SDS micelles.