The purpose of the study was to develop an optimum formulation of self-emulsifying drug delivery systems (SEDDS) containing puerarin and to evaluate its absolute bioavailability. Using oleic acid as oil, Tween-80 as surfactant and propylene glycol as cosurfactant, a series of mixtures comprising oleic acid, propylene glycol and Tween 80 were prepared and their self-emulsifying properties were studied. Pseudo-ternary phase diagrams were constructed to identify the efficient self-emulsification region and particle sizes of the resultant emulsions were determined using a laser diffraction sizer. From these studies, an optimized formulation consisting of oil (17.5%), Tween-80 (34.5%) and cosurfactant (34.5%) was selected and its absolute bioavailability in beagle dogs after oral administration was about 24.8%. The data suggest the use of SEDDS to provide a potential way of puerarin administered orally.
2007 The Pharmaceutical Society of Japan