Preparation and characterization of quercetin nanosuspensions using gypenosides as novel stabilizers

To study the potential of gypenosides as natural stabilizers for the production of nanosuspensions, quercetin (QUE) was chosen as a model drug to prepare nanosuspensions stabilized by gypenosides. Here, high-speed shearing and high-pressure homogenization were used to obtain QUE nanosuspensions (QUE-NS). Different QUE-NS were prepared by changing the concentration and type of stabilizer to evaluate the stabilization efficiency of gypenosides. The results showed that the ability of gypenosides to stabilize nanosuspensions was superior to that of the conventional stabilizers at low concentrations. Using transmission electron microscopy, QUE-NS were observed to have the nanosized particles (less than 500 nm) and present a lumpy morphology. Due to the reduction of particle size, the in vitro dissolution rate and antioxidant activity of QUE-NS were significantly higher than that of QUE coarse drug. Powder X-ray diffraction and fourier-transform infrared spectroscopy showed that there was no significant difference in the chemical structure and crystal state of QUE during the production process. According to the results of stability studies, QUE-NS stabilized with gypenosides exhibited good storage stability. In conclusion, preparation of the nanosuspensions was feasible using gypenosides as novel stabilizers. Nanosuspensions stabilized by gypenosides could be used as a potential strategy for improving the solubility of poorly water-soluble drugs.