Surface, Micellar, and Aggregation Behavior of Non-cytotoxic Imidazolium Gemini Surfactants

The micellar, surface, and aggregation properties of biocompatible, imidazolium-based hydroxyl group-containing gemini surfactants, 1,1 '-(propane-1,3-diyl-2-ol) bis(3-alkyl-1H-imidazol-3-ium)bromide, [C(n)Im-3OH-ImC(n)]Br-2, were studied. The surface parameters like maximum surface excess concentration at air/water interface (Gamma(max)), the minimum surface area occupied by surfactant molecules (A(min)) and the related thermodynamic parameters such as, standard Gibbs free energy of micellization (Delta Gm0), standard free energy of adsorption (Delta Gad0), and free energy of surface at equilibrium (Gmins) were also determined from the surface parameters. The aggregation behavior has been elucidated from transmission electron microscopy (TEM) and dynamic light scattering (DLS) techniques which showed that these gemini surfactants have potential self-aggregation efficiency. Besides, some other physicochemical properties like foam stability, emulsifying power, and viscosity have been determined. The structural features of [C(n)Im-3OH-ImC(n)]Br-2 enhance their surface-active properties. These features of gemini surfactants are of primary significance from pharmaceutical and biomedical viewpoints. The gemini surfactants may have great implications in drug formulations and delivery owing to their prominent aggregation and non-cytotoxic nature.