ABSTRACT
Objective To study the feasibility of preparing insoluble flavonoids nanosuspensions (NS) by miniaturized media milling. Methods The miniaturized media milling method was constructed with the magnetic stirrer, vial and zirconia beads as the power plant, milling chamber and milling media to prepare the nanosuspensions of four flavonoids: quercetin (QCT), baicalin (BCN), puerarin (PRN), and silymarin (SLR). The process of stirring speed, the amount of milling medium and the milling time were optimized with average particle size, polydispersity index (PDI) and stability index (SI) as indicators. Results The optimized process of stirring speed, the amount of milling medium and the milling time of QCT-NS, BCN-NS, PRN-NS and SLR-NS were QCT-NS 800 r/min, 8 h, 1:1, BCN-NS 800 r/min, 24 h, 1:1, PRN-NS 800 r/min, 24 h, 2:1, SLR-NS 800 r/min, 12 h, 1:1. The average particle sizes of QCT-NS, BCN-NS, PRN-NS and SLR-NS prepared with the optimized process were below 400 nm. The PDI of QCT-NS, BCN-NS and SLR-NS was below 0.3 (PRN-NS) and SI was above 0.75, the PDI and SI of PRN-NS were 0.41 and 0, respectively. Conclusion The miniaturized media milling methods for preparation of insoluble flavonoids NS is simple, stable and feasible, and it is worth for further study.