Polyion complex vesicles (PICsomes) are characterized by their unique three-layered semipermeable nanomembrane structures, in which a unilamellar PIC layer is sandwiched by poly(ethylene glycol) layers, and have gathered much attention as nano-scaled drug vehicles. Herein, the crosslinking degree of the nanomembrane in the PICsome was controlled systematically for the first time. Permeability of the PICsome nanomembrane was evaluated through a kinetic study of the release of macromolecular cargoes from the PICsome. The degree of crosslinking in the nanomembrane successfully regulated the release behavior. Moreover, the shape and size of the macromolecular solutes were found to be critical factors determining their transport from the inner aqueous phase of the PICsome to the external environment. The results indicate that the unique three-layered structure of PICsome membranes plays a key role in modulating solute transport. These findings will provide a rational strategy for the development of nanomembrane-based controlled-release systems.

聚离子复合物囊泡（PICsomes）的特征在于其独特的三层半透性纳米膜结构，其中单层PIC层被聚（乙二醇）层夹在中间，并作为纳米级药物载体而备受关注。在此，首次对PICsome中的纳米膜的交联度进行了系统地控制。通过动力学研究从PICsome释放大分子货物来评估PICsome纳米膜的渗透性。纳米膜中的交联度成功地调节了释放行为。此外，发现大分子溶质的形状和大小是决定其从PICsome的内部水相向外部环境迁移的关键因素。结果表明，PICsome膜独特的三层结构在调节溶质转运中起关键作用。这些发现将为开发基于纳米膜的控释系统提供合理的策略。