聚乙二醇/β谷甾醇双接枝壳聚糖共聚物纳米粒的体外释放与体内分布考察

目的考察一种新型两亲性壳聚糖衍生物—聚乙二醇（PEG）／B谷甾醇双接枝壳聚糖（Psc）在水中自组装形成的纳米粒的性能及组织分布，为作为抗肿瘤药物载体的可行性进行理论探讨。方法采用芘荧光探针技术测定PSC的临界聚集浓度（CAC）；用香豆素-6为模型药物，透析法考察胶柬的体外释放度行为；考察载香豆素-6的PSC纳米粒在小鼠体内的组织分布。结果CAC为0．02g／L，载药量为3．3％，包封率为75％。较长链PEG的纳米粒比修饰短链PEG的纳米粒在脑部的分布有所增加；两种载药PSC纳米粒在肺部浓度较高；修饰PSC纳米粒在肾、心中分布均较少。结论PSC胶束可作为香豆素的载体，具有良好的应用前景。

Distribution In Vivo and Release In Vitro of Polyethylene Glycol/β-Sitosterol Chitosan Copolymer Nanoparticles

Objective To investigate the performance and the tissue distribution of the nanoparticles formed by self- assembling in water with a novel amphiphilic chitosan derivant-polyethylene glycol（PEG）/β sitosterol double grafted ehitosan（PSC） so as to theoretically explore the feasibility as anti- tumor drug carrier. Methods The critical aggregation concentration（CAC） of the copolymer PSC was measured by the pyrene fluorescent probe technique; with coumarin- 6 as the model drug, the in vitro release behavior of the micelle was investigated by the dialysis method; the tissue distribution of the PSC nanoparticles carrying coumarin- 6 in mice in vivo were in- vestigated. Results CAC was 0. 02 g/L, the drug-loading capacity was 3.3% and the encapsulation rate was 75%. The distribution in brain of nanoparticles of longer- chain PEG was increased to some extent compared with the modified short chain PEG; the two kinds of drug- loading PSC nanoparticles had the higher concentration in lung; at the same time the modified PSC nanoparticles were distributed little in kidney and heart. Conclusion The PSC micelle may be used as the coumarin carrier and has better application prospect.