Microemulsions of Sorbitans and its Derivatives for Iontophoretic Drug Delivery

摘要

This study explains the development and characterization of microemulsions for iontophoretic drugdelivery. The microemulsions were developed using a pseudo ternary phase diagram. Biphasicformulations of sesame oil were developed using a mixture of span 80 and tween 80 as surfactantmixture (Smix). The composition of the Smix, sesame oil and water was varied. Microemulsions wereformed at a Smix concentration of > 60 %. The formulations were characterized by microscopic studies,FTIR spectroscopy, viscosity, mechanical analysis and impedance analysis. A model drug,metronidazole, was incorporated in the microemulsions to check its drug release behavior. FTIRspectra suggested no interactions amongst the formulation components and the drug. The viscosity andfirmness was higher in the microemulsion possessing lower water/surfactant ratio. The microemulsionswere electroconductive in nature. The microemulsions showed 42-47 % increase in the amount ofmetronidazole released under the influence of current as compared to the passive release. The releaseprofile followed zero order release kinetics. The developed microemulsions can be used foriontophoretic drug delivery applications.