Freeze-drying of oleanolic acid-loaded nanosuspensions / 中国中药杂志

ABSTRACT

<p><b>OBJECTIVE</b>Several cryoprotectants were employed to study the protective effect on the freeze-drying process of the oleanolic acid-loaded nanosuspensions (OLA-LS) in order to select the optimum formulation.</p><p><b>METHOD</b>The protective effect was evaluated by measuring the mean particle size of samples before and after freeze-drying process.</p><p><b>RESULT</b>Sucrose with the concentration of 10% was selected as the optimum cryoprotectant. The average size of excellent sample was 236.3 nm (versus 211.2 nm of fresh one), and a much higher polydispersity index of 0.242 (versus 0.180).</p><p><b>CONCLUSION</b>The optimum lyophilized powder could be obtained with suitable type of cryoprotectant with appropriate concentration and proper freeze-drying conditions.</p>