Lipid emulsion as a drug delivery system for breviscapine: formulation development and optimization

In this study, we developed an optimized formulation of a breviscapine lipid emulsion (BLE) and evaluated the physicochemical properties and in vivo pharmacokinetics of BLE in rats. For the preparation of the lipid emulsion, soybean oil and oleic acid were used as the oil phase, lecithin and poloxamer 188 as surfactants and glycerol as co-surfactant. An optimized formulation consisting of soybean oil (10.0%), oleic acid (0.9%), lecithin (1.5%), poloxamer 188 (0.4%), and glycerol (2.25%) was selected. The results showed that the average particle size, polydispersity index, and zeta potential of the optimized formulation were 183.5 ± 5.5 nm, 0.098 ± 0.046, and -35.0 ± 2.5 mV, respectively. The BLE was stable for at least three month at room temperature. After a single intravenous dose of 4 mg/kg to rats, the AUC of scutellarin from the lipid emulsion was about 1.5-fold higher than that of the commercial product (breviscapine injection). In conclusion, the optimized formulation of BLE showed positive results over the commercial product in terms of the physicochemical properties and pharmacokinetics of BLE in rats.