Polymeric drug delivery systems for major diseases have experienced considerable development in the past decades due to the versatility of polymer chemistry. However, self-assembled micelles from multimacromolecules suffer from poor stability and imprecise architecture. Unimolecular micelles have many unique advantages, including high stability, accurate architecture and high drug loading. Herein, a series of well-defined, unimolecular, star-shaped, polymers (β-CD-s-PAA-PTX), with β-cyclodextrin as a core, poly(acrylic acid) (PAA) as branches, and the anticancer drug paclitaxel covalently linked to the branches, were synthesized. The β-CD-s-PAA-PTX can form unimolecular micelles in aqueous solutions, which was attributed to their amphiphilic structure. Drug loading increased with the increase of the molecular weight of the star-shaped polymer β-CD-s-polyacrylic acid (β-CD-s-PAA), and the maximum drug loading reached 59 wt%. The fate of the unimolecular micelles with different molecular weights in tumor-bearing mice was investigated. Unimolecular micelles with low molecular weights could not effectively accumulate in tumors, while high-molecular weight unimolecular micelles tended to accumulate in tumor sites. This study provided the effect of the molecular weights of the β-CD-cored unimolecular micelles on their in vivo behavior.

在过去的几十年中，由于高分子化学的多功能性，用于主要疾病的高分子药物递送系统已经取得了长足的发展。然而，来自多分子的自组装胶束具有差的稳定性和不精确的结构。单分子胶束具有许多独特的优势，包括高稳定性，准确的结构和高载药量。在此，以β-环糊精为核，聚丙烯酸（PAA）为支链的一系列定义明确的单分子星形聚合物（β -CD-s-PAA-PTX）和抗癌剂合成了与分支共价连接的药物紫杉醇。该β-CD-s-PAA-PTX可以在水溶液中形成单分子胶束，这归因于它们的两亲结构。随着星形聚合物β -CD-s-聚丙烯酸（β -CD-s-PAA）分子量的增加，药物载量增加，最大药物载量达到59 wt％。研究了荷瘤小鼠中不同分子量单分子胶束的命运。低分子量的单分子胶束不能有效地积聚在肿瘤中，而高分子量的单分子胶束则倾向于积聚在肿瘤部位。该研究提供了β -CD-核心的单分子胶束的分子量对其体内行为的影响。