We reported SN38-loaded polymersomes formulated with amphiphilic block copolymers based on HPMA and either ε-caprolactone or lactic acid through employing ring-opening polymerization, carbodiimide chemistry and a reversible addition−fragmentation chain transfer polymerization technique. In this regard, we successfully synthesized five chimeric polymersomes based on different percentage of the synthesized copolymers. The prepared chimeric polymersomes based on PCL-b-PHPMA:PLA-b-PHPMA at ratio of 1:3 exhibited superior loading capacity in comparison with other chimeric polymersomes.

In order to increase therapeutic index of the prepared systems, AS1411 aptamer was implemented as targeting ligand. In vivo study revealed that the intravenous single dose injection of targeted chimeric polymersomes to C26 tumor bearing mice had remarkable efficacy in inhibiting tumor growth. It could be concluded that the chimeric polymersomes fabricated from PCL-b-PHPMA and PLA-b-PHPMA at a ratio of 1:3 have great potential for SN38 encapsulation while providing controlled sustained release properties with targeting capability via AS1411 aptamer conjugation.

我们报道了采用开环聚合，碳二亚胺化学和可逆加成-断裂链转移聚合技术，由基于HPMA的两亲嵌段共聚物和ε-己内酯或乳酸配制的SN38聚合物小体。在这方面，我们基于合成共聚物的不同百分比成功合成了五个嵌合聚合物小体。与其他嵌合聚合物囊泡相比，基于PCL- b- PHPMA：PLA- b- PHPMA的比例为1：3的制备的嵌合聚合物囊泡表现出优异的负载能力。

为了增加所制备系统的治疗指数，AS1411适体被用作靶向配体。体内研究表明，向带有C26肿瘤的小鼠静脉内单剂量靶向嵌合聚合物囊泡注射具有抑制肿瘤生长的显着功效。可以得出结论，由PCL- b- PHPMA和PLA- b- PHPMA以1：3的比例制备的嵌合聚合物囊泡具有很大的SN38包封潜力，同时可通过AS1411适体偶联提供靶向控制的缓释特性。