Abstract: Objective To investigate the absorption and safety of resveratrol  self-microemulsion in rats. 
Methods The optimal formula for resveratrol self-microemulsion was chosen and determined using a pseudo-ternary phase diagram. The quality characteristics of the self-microemulsion were evaluated in terms of particle size, morphology, dissolution, and stability. The intestinal absorption of resveratrol was investigated through in vivo intestinal absorption tests, and the oral bioavailability of the self-microemulsion was assessed using pharmacokinetic tests. The safety of self-microemulsion was evaluated through an acute oral toxicity test in mice. 
Results The optimal formula for the resveratrol self-microemulsion included 22 g triacetate, 27 g polyoxyethylene castor oil, 13.5 g polyoxyethylene hydrogenated castor oil, 37.8 g isopropyl alcohol, and 3.5 g resveratrol. This mixture had a uniform particle size (14.528±0.314) nm and good stability. Compared with the suspension phase, the absorption rate constant (Ka) and apparent distribution coefficient (Papp) of the self-microemulsion were (2.131±0.576) times and (2.382±0.688) times respectively,  the time to reach peak blood concentration and mean residence time were (3.272±0.403) times and (2.531±0.569) times respectively, and both the peak concentration and the area under the curve were (3.588±0.454) times and (10.985±2.997) times respectively. No toxic reactions or obvious weight changes were observed in the suspension group, microemulsion adjuvant group, or self-microemulsion group (P＞0.05). 
Conclusion The self-microemulsion effectively improves the stability of resveratrol, significantly enhances its intestinal absorption and oral bioavailability, and has good safety, providing an experimental basis for expanding the clinical application of resveratrol. 

Key words: resveratrol, pharmacokinetics, self-microemulsion