Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 15 North Third Ring Road, Chaoyang District, 100029 Beijing, P.R. China.
Chimie ParisTech, PSL University Paris, CNRS, Institut de Recherche de Chimie Paris, UMR8247, 11 rue Pierre et Marie Curie, Paris 75231 Cedex 05, France.
ACS Nano. 2021 Jan 26;15(1):884-893. doi: 10.1021/acsnano.0c07400. Epub 2020 Dec 28.
Structuring pores into stable membrane and controlling their opening is extremely useful for applications that require nanopores as channels for material exchange and transportation. In this work, nanoporous vesicles with aggregation-induced emission (AIE) properties were developed from the amphiphilic polymer PEG550-TPE-Chol, in which the hydrophobic part is composed of a tetraphenylethene (TPE) group and a cholesterol moiety and the hydrophilic block is a poly(ethylene glycol) (PEG, = 550 Da). Two stereoisomers, -PEG550-TPE-Chol and -PEG550-TPE-Chol, were successfully synthesized. These thermally stable stereoisomers showed distinct self-assembly behavior in water: -PEG550-TPE-Chol formed classical vesicles, while -PEG550-TPE-Chol self-assembled into cylindrical micelles. Interestingly, / mixtures of PEG550-TPE-Chol (/ = 60/40), either naturally synthesized without isomers' separation during the synthesis or intentionally mixed using and isomers, constructed perforated vesicles with nanopores. Moreover, under the illumination of high intensity UV light (365 nm, 15 mW/cm), the classical vesicles of PEG550-TPE-Chol were perforated by its counterparts generated from the photoisomerization, while the cylindrical micelles of -PEG550-TPE-Chol interweaved to form meshes and nanoporous membranes due to the -isomers produced by photoisomerization. All of these assemblies in water emitted bright cyan fluorescence under UV light, while their constituent molecules were not fluorescent when solubilized in organic solvent. The AIE fluorescent normal vesicles and nanoporous vesicles may find potential applications in biotechnology as light-gated delivery vehicles and capsules with nanochannels for material exchange.
将孔结构化到稳定的膜中并控制其打开对于需要纳米孔作为材料交换和运输通道的应用非常有用。在这项工作中，从两亲聚合物 PEG550-TPE-Chol 中开发出具有聚集诱导发射 (AIE) 性质的纳米多孔囊泡，其中疏水性部分由四苯乙烯 (TPE) 基团和胆固醇部分组成，亲水性部分是聚（乙二醇）（PEG， = 550 Da）。成功合成了两种立体异构体，-PEG550-TPE-Chol 和 -PEG550-TPE-Chol。这些热稳定的立体异构体在水中表现出明显不同的自组装行为：-PEG550-TPE-Chol 形成经典囊泡，而 -PEG550-TPE-Chol 自组装成圆柱状胶束。有趣的是，PEG550-TPE-Chol 的 /混合物（/ = 60/40），无论是在合成过程中没有异构体分离而自然合成的，还是使用 和异构体有意混合的，都构建了具有纳米孔的穿孔囊泡。此外，在高强度紫外光（365nm，15mW/cm）照射下，PEG550-TPE-Chol 的经典囊泡被其 光异构体产生的 穿孔，而 -PEG550-TPE-Chol 的圆柱状胶束相互交织形成网格和纳米多孔膜由于 光异构化产生的 -异构体。所有这些在水中的组装体在紫外光下发出明亮的青色荧光，而其组成分子在溶解在有机溶剂中时没有荧光。AIE 荧光正常囊泡和纳米多孔囊泡可能在生物技术中有潜在的应用，作为光控输送载体和具有纳米通道的胶囊，用于材料交换。
