Deciphering the influence of salt on the mixed micellization of drug Domiphen Bromide and tri-substituted SAIL [C12bmim][Br] mixture

Abstract

The mixed micellization between amphiphilic drug Domiphen Bromide (DB) and tri-substituted SAIL 1-dodecyl-2,3-dimethylimidazolium bromide [C12bmim][Br] in absence/attendance of 10 mM NaH2PO4.2H2O has been explored through conductivity and surface tension measurements at various temperatures. Conductance was used to determine the critical micelle concentration (cmc) and other thermodynamic parameters while the interfacial parameters were derived from the surface tension which were helpful in figuring out the phenomenon that was occurring at the interface. The mixed micellar system has been investigated using three distinct theoretical models: the Rubingh model, the Motomura model, and the Rodenas model. The obtained results i.e. cmcid >cmcexp implies synergism between the studied components, DB and [C12bmim][Br]. Larger negative values ofβ indicated a highly effective interaction between the two components. Further influence of salt addition on the mixed system has also been discussed. The negative magnitudes of the Gibbs free energy of micellization (ΔGm0) between the two amphiphiles investigated suggested the creation of spontaneous mixed micelles.