The phase behavier and the physicochemical properties of mixed surfactants microemulsions as drug delivery systems

The interaction between triphenylphenoxy polyoxyethylenyl polyoxypropy-lene (PEP) and sodium dodecyl sulfate (SDS) were determinted using surface tension method. The mixed critical micelle concentration (CMC) values determined from the experimental data were used to calculate the molecular interaction parameters according to regular solution theory. The pseudoternary phase behavior of the mixed micromulsion systems containing bifenthri was investigated at different temperatures and salts of different concentration. The system structural transition in this one-phase microemulsion region was carried out using electrical conductivity The results showed strong synergistic interaction in the micelles of (PEP+SDS) systems. The mixed micromulsions systems showed temperature insensitivity. Electrical conductivity confirm that the system undergoes a continuous structural transition of microemulsions from W/O via bicontinuous phase to O/W.