Novel self-assembling nanogels: Stability and lyophilisation studies
Novel self-assembling nanogels: Stability and lyophilisation studies
复制标题
DOI：
10.1016/j.ijpharm.2006.09.052
复制
发表时间：
2007-03-06
影响因子：
5.8
通讯作者：
Gref, R.
中科院分区：
文献类型：
--
作者：
Doloud-Mahammed, S.;Couvreur, P.;Gref, R.
基于疏水修饰右旋糖酐（MD）和β -环糊精聚合物（p β - CD）结合的新型超分子纳米组件（纳米凝胶）的稳定性通过两种互补的方法进行了研究：(i)尺寸测量和（ii）使用Turbiscan光学分析仪进行浊度实验。无论两种聚合物溶液的浓度如何，均可获得约120-150 nm的纳米凝胶。在低浓度下，悬液的平均直径随贮存时间的变化不大。但随着时间的推移，浓缩后的颗粒趋于失稳，平均直径增大。尺寸测量和Turbiscan研究表明，MD-p β CD纳米凝胶悬浮液中的不稳定仅是由于颗粒聚集和/或融合，而不会发生沉淀或乳化。MD-p β CD悬浮液的不稳定导致形成高粘性相，作为最终状态。此外，两种方法都表明，在浓缩的MD-p β - CD悬浮液中，聚集和/或融合现象比稀释的MD-p β - CD悬浮液更为明显。在4℃的温度下，可以提高MD-p β CD悬浮液的稳定性。最后，我们发现冷冻干燥是MD-p β CD纳米组件长期储存的一种方便方法。(c) 2006 Elsevier B.V.版权所有
The stability of new supramolecular nanoassemblies (nanogels), based on the association of a hydrophobically modified dextran (MD) and a beta-cyclodextrin polymer (p beta CD), has been studied by two complementary methods: (i) size measurements and (ii) turbidity experiments using a Turbiscan optical analyser. Nanogels of about 120-150 nm were obtained whatever the concentration of the two polymer solutions. At low concentrations, the suspensions presented little mean diameter variations upon storage. However, the concentrated ones tended to destabilize and their mean diameter increased upon time. Size measurements and Turbiscan investigations have demonstrated that destabilization in the MD-p beta CD nanogel suspension was only due to particle aggregation and/or fusion, as no sedimentation or creaming occurred. The destabilization of MD-p beta CD suspensions led to the formation of a highly viscous phase, as a final state. Moreover, the two methods have shown that aggregation and/or fusion phenomena were more pronounced in the concentrated MD-p beta CD suspensions than in the diluted ones. The stability of MD-p beta CD suspensions could be improved by their storage at 4 degrees C. Finally, freeze-drying was found to be a convenient method for the long-time storage of MD-p beta CD nanoassemblies. (c) 2006 Elsevier B.V. All rights reserved.