A Thermodynamic Micellization and Hemolysis Evaluation of Polysorbate Surfactants in Combination with Short-Chain Alcohols

Surface active agents have been used in many pharmaceutical formulations for different purposes as penetration enhancers. In this study, the penetration enhancement activity of four nonionic surfactants from polyoxyethylene sorbitan fatty acid esters alone and in combination with some short-chain alcohols on red blood cells were investigated. Hemolysis at different concentrations of each nonionic surfactant (0.1, 0.2, 0.5, 1, and 2%) and ethanol, isopropyl alcohol, glycerol, and propylene glycol (0.5, 1, 2, 5, and 10%w/v) were investigated. Critical micelle concentration (CMC) and micellization thermodynamic parameters of tween 80 in presence of ethanol and glycerol at different concentrations were determined. The influence of the ethanol and glycerol on nonionic surfactant micelle formation was evaluated by determining CMC and micellization thermodynamic parameters of tween80 at different concentrations of alcohol-tween mixtures. The mixture of Tween 20 and glycerol have the lowest hemolytic activity while tween 80-ethanol mixture has the highest hemolysis activity. The self-aggregation of surfactant monomers was affected by short-chain alcohols. The structure breaking ability of alcohol and their interactions with the hydrophilic-hydrophobic groups of surfactants might be the main factors for changing the micelle formation. The CMCs of tween 80 was incremented by increasing the concentration of alcohol. The results indicated that by adding and increasing short chain alcohols the CMCs increased also the CMCs were increasing through raising the temperature (while in the presents of surfactants alone the CMCs decreased by raising temperature).