3种干燥方法对壳聚糖微球支架物理性能和载药性能的影响

ObjectiveThe purpose of this study is to investigate the effects of different drying methods on the physical properties and drug delivery of chitosan microspheres.MethodsThree types of drying methods were utilized, including air drying and freeze drying after freezing at -20 ℃ (slow cooling) and at -80 ℃ (fast cooling). The physical properties of microspheres were characterized. Utilizing bovine serum albumin (BSA) as the model drug, thein-vitrorelease behaviors of drug-loaded beads were investigated.ResultsBy comparing the physical properties of the different drying methods, the microspheres’ diameters, porosities, and surface area were observed to increase successively from air drying and slow cooling to fast cooling, whereas the pore size and the swelling and degradation rates varied. The drug-loading experiments revealed that the loading capacity of air-dried microspheres was the lowest and the release rate was the slowest. Although the loading capacity of fast cooling microspheres was high, an obvious burst release was observed. The loading capacity of slow cooling microspheres was similar to that of the fast cooling microspheres and the loaded BSA can be released continuously.ConclusionThe results indicate that different drying methods can affect the physical properties of chitosan microspheres, which further influence drug loading and release.