[Preparation of nanosuspension of quercetin with a miniaturized milling method]

The nanosuspension of quercetin (QT-NS) was prepared by a miniaturized milling method, and the process was optimized by Box-Behnken response surface method. Then the accumulative release rate of QT-NS in vitro was determined. The results showed that the optimal process parameters were as follows: ZrO2 4.5 mL, milling speed 690 r•min⁻¹ and milling time 1.5 h; the particle size of QT-NS was (169±5) nm, polydispersity index of 0.204±0.006 and stability index of 0.827±0.014, respectively. There was a little deviation between the theoretically predicted value and the measured value, indicating that this model had a good prediction effect. The accumulative release rate in vitro of QT-NS in 120 min was significantly higher than that of the raw drug and physical mixture. This simple low-cost miniaturization approach could prepare QT-NS successfully, and could provide reference for the formulation of the nanosuspension.