Abstract: To prepare sinomenine phospholipids complex nanostructured lipid carriers,and in vitro and in vivo in SD rats were evaluated.Solvent evaporation method was used to prepare sinomenine phospholipids complex,and ultrasonic emulsification method was adopted to prepare its nanostructured lipid carriers.The basic physicochemical properties,including particle size,zeta potential,encapsulation efficiency,drug loading and drug release in vitro were studied.The pharmacokinetics and bioavailability were compared after oral administration of sinomenine and its phospholipids complex nanostructured lipid carriers.The results showed that particle size,zeta potential,encapsulation efficiency and drug loading of sinomenine phospholipids complex nanostructured lipid carriers were 201.32±5.05 nm,-22.2±1.5 mV,80.31±1.01% and 4.42±0.28%,respectively.The drug release in vitro has a characteristic of slow release,which was better agreed with Weibull kinetics model and the equation was LnLn(1/1-Mt/M∞)=0.576 6Lnt-1.478 1 (r=0.988 8).The pharmacokinetic results showed that the pharmacokinetic behavior was changed,the absorption was enhanced,the residence time was extend and the bioavailability of sinomenine was enhanced by 1.75 times.Therefore,sinomenine phospholipids complex nanostructured lipid carriers could promote the drug absorption and enhance the bioavailability significantly.

Key words: sinomenine, phospholipids complex, nanostructured lipid carriers, pharmacokinetics, bioavailability