Preparation and Evaluation of Retinoic Acid Selfmicroemusifying Drug Delivery System

Retinoic acid selfmicroemusifying drug delivery system (SMEDDS) was developed and evaluated. According to the pseudoternary diagram, Cremorphor RH40(RH40) and Tween 20(T20) were selected as emulsifiers. The formulations were screened by droplet size of microemulsion generated upon dilution and emulsification time. The droplet size of microemulsion was (25.8±3.0)nm when m(RH40)∶m(T20) was 1∶1. The dissolution profiles of retinoic acid in different mediums were significantly improved in SMEDDS, which is advantageous to improve oral bioavailability of retinoic acid.