Formulation and physical characterization of microemulsions containing isotretinoin

Physical properties of microemulsions containing tween80 as surfactant and tetraglycol as cosurfactant, were investigated for their potential to form microemulsion templates as drug delivery vehicles for isotretinoin. Bile salt was used as edge activator in skin permeation and surfactant protein B (SP-B1–25) may be helpful in drug delivery and reducing sebum level. All of the compounds used to formulate the microemulsions were pharmaceutically acceptable and biocompatible. The drug-containing systems were characterized in regard to their transdermal parameters. Physiologically well-tolerated and physically stable multiple-component systems were developed. The concentrations of surfactants and cosurfactants which are necessary to form stable systems were evaluated. Microemulsions were characterized using polarized light microscopy, photon correlation spectroscopy (PCS), electric conductivity and rheometry. The influence of isotretinoin on the physical parameters of the preparation was investigated.