N-氢化可的松琥珀酰基壳聚糖的制备及其体外性质的初步考察

Preparation of N-hydrocortisone succinyl chitosan and elementary study of its properties in vitro

目的 将氢化可的松与壳聚糖进行偶连，以改善其溶解性，延缓其释放。方法以琥珀酰基为连接臂将氢化可的松与壳聚糖进行偶连（N-氢化可的松琥珀酰基壳聚糖），并通过红外及紫外光谱对偶连物的化学结构进行确证，分别采用溶解实验的方法及动态透析法考察偶连物的溶解性及体外释放特征。结果当氢化可的松琥珀酰基的取代度为15．5％时，N-氢化可的松琥珀酰基壳聚糖易溶于酸性水溶液，而在中性及弱碱性水溶液中形成凝胶；其体外释放速度缓慢，36h内的总释放量为5．8％。结论 壳聚糖作为氢化可的松的高分子载体，能明显改善其溶解性，延缓其释放。

Objective To improve the solubility of hydrocortisone and sustain its release by conjugating it with chitosan. Methods The conjugate of hydrocortisone with chitosan through succinyl linkages （N-hydrocortisone succinyl chitosan） was prepared and its chemical structure was confirmed by UV and IR. The solubility of N-hydrocortisone succinyl chitosan was studied in the solutions with pH ranged from 2 to 14. Its release behavior in vitro was assessed by dynamic dialysis method. Results When the substitution degree of hydrocortisone suecinyl group was 15.5%, N-hydrocortisone succinyl chitosan was soluble in acidic solution and formed hydrogel in litmusless and alkalescence solution. The release rate of hydrocortisone from N-hydrocortisone succinyl ehitosan was very slow and the total release amount was 5.8% in 36 h. Conclusion Being used as the polymeric carrier of hydrocortisone, chitosan can improve its solubility and sustain its release.