Formulation of Nanoparticle Containing Everolimus Using Microfluidization and Freeze-Drying.

The aims of this study were to improve in vitro dissolution property of poorly water-soluble everolimus (EVR) for enhanced bioavailability without using organic solvents and characterize the effects of microfluidization and freeze-drying on physicochemical properties of EVR nanosuspension and nanoparticle, respectively. EVR nanosuspension was prepared using microfluidization with various types and concentrations of stabilizers. After that, it was solidified into nanoparticle using freeze-drying with various concentrations of xylitol, a cryoprotectant. The particle size, zeta potential, physical stability, and chemical stability of EVR nanosuspension and nanoparticle were measured. In vitro release of EVR nanoparticle was also measured and compared with that of physical mixture. Zero point five percent (w/w) poloxamer 407 (P407) was chosen as the stabilizer considering particle size, zeta potential, and yield of EVR nanosuspension. Freeze-drying with 1% (w/w) xylitol improved both physical and chemical stability of EVR nanoparticle. In vitro release test showed improved dissolution property compared to that of physical mixture, implying enhanced bioavailability.