Nanoemulsion Formulations for Improved Oral Delivery of Poorly Soluble Drugs

The objective of this study was to develop nanoemulsion formulations for enhancement of oral bioavailability of paclitaxel, a model hydrophobic drug and P-glycoprotein substrate. The oil-in-water (o/w) nanoemulsions were made with pine nut oil as the internal oil phase, egg lecithin as the primary emulsifier, and water as the external phase. Stearylamine and deoxycholic acid were used to impart positive and negative charge to the emulsions, respectively. The formulated nanoemulsions had a particle size range of 90-120 nm and zeta potential ranging from +34 mV to -56 mV. Following oral administration to C57BL/6 mice, a significantly higher concentration of paclitaxel was observed in the systemic circulation when administered in the nanoemulsion relative to control aqueous solution. The results of this study suggest that nanoemulsions are promising novel formulations that can enhance the oral bioavailability of poorly soluble drugs.