Abstract: Solvent evaporation method was adopted to prepare lappaconitine phospholipids complex,and thin-film ultrasonic method was used to prepare its solid lipid nanoparticles.The basic physicochemical properties of lappaconitine phospholipids complex solid lipid nanoparticles were also studied.The pharmacokinetics and bioavailability were compared after oral administration of lappaconitine and its phospholipids complex solid lipid nanoparticles.The results showed that particle size,zeta potential and encapsulation efficiency of lappaconitine phospholipids complex solid lipid nanoparticles were (224.37±1.93) nm,(-6.14±0.09) mV and (85.08±1.84)%,respectively.The pharmacokinetic results showed that T_max, C_max, AUC_0~t, AUC_0~?had statistical significance (P<0.05 or P<0.01),and the bioavailability was enhanced by 2.58 times.Therefore,lappaconitine phospholipids complex solid lipid nanoparticles could enhance the bioavailability significantly.

Key words: Lappaconitine, encapsulation efficiency, solid lipid nanoparticles, bioavailability