Micellar solubilization of cetaben sodium in surfactant and lipid solutions

Cetaben sodium solubilities were evaluated by micellar solubilization in various surfactants and lipid solvents. At pH 8, the relationship between cetaben sodium solubility and surfactant concentration delineated apparent saturable kinetics; at pH 4.9, the relationship between the two parameters was linear. In the presence of 0.5% sodium taurocholate and polysorbate 80, cetaben sodium solubility increased as the medium pH was increased; however, in the presence of 0.5% poloxamer 188, cetaben sodium solubility revealed a hyperbola when the pH was changed from 4.9 to 8.0. Cetaben sodium solubility was enhanced greatly by mixed physiological surfactants, full-strength caprylic-capric monodiglycerides or monodiglycerides, when compared to a single surfactant system. Cetaben sodium solubility is influenced by pH, surfactant type, surfactant concentration, lipid solvent type, and the simultaneous presence of surfactants or phospholipids.