Interaction of anionic surfactants with collagen

The interaction of anionic surfactants with collagen was studied using prep ared fibres of beef achilles tendons, sodium dodecylbenzene sulphonate (SDB S) and sodium dodecylsulphate (SDS). The binding parameter (p) was derived to estimate a type of interaction, its construction follows from an assumed two-stage interaction in which both stages differ in the character of thei r bonds. The parameter was defined as the amount of surfactant bound by Cou lomb interactions divided by the total amount of adsorbed surfactant and wa s calculated from equilibrium sorption data and front the concentration of surfactant counterions after reaction. High parameter values confirm that, regardless of the magnitude of surfactant sorption, binding predominantly p roceeds through Coulomb interactions until the amount of bound surfactant c orresponding to the concentration of charged reaction sites in collagen is reached while part of the surfactant is obviously bound through a different mechanism. The relationship between the binding parameter and amount of bo und surfactant was supported by determining the binding constant K for the two surfactants.