Cao Zhaozhen, Hao Aiyou, Xing Pengyao
School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
Nanoscale. 2021 Jan 21;13(2):700-707. doi: 10.1039/d0nr06835g.
A chiral vesicle system with photo-regulated chiroptical properties including Cotton effects and circularly polarized luminescence (CPL) was reported. Photoresponsive cyanostilbene was conjugated to the cholesteryl group, which provides chiral centers and lipophilic domain for the flexible vesicle membrane formation. The building block self-assembled into vesicles with exciton Cotton effects and CPL. The high dissymmetry g-factor of CPL at 10-2 order of magnitude was achieved. Upon UV light irradiation, Cotton effects were enhanced with an elevated g-factor by 3-fold, while the CPL dissymmetry factor showed a light irradiation resistance. A hydrophobic fluorescent dye (Nile Red) was loaded into vesicle membranes to allow energy transfer and chirality transfer to give red color CPL with retained high g-factor, while resistance to the UV light irradiation of vesicles was enhanced after loading the fluorescent dye. This study highlights the fabrication of the chiral vesicle system with noninvasively stimulus-responsive chiroptical properties, which may provide new thoughts for the fabrication of smart chiroptical materials in aqueous media.
报道了一种具有光调节手性光学性质（包括科顿效应和圆偏振发光（CPL））的手性囊泡系统。光响应性氰基二苯乙烯与胆固醇基团共轭，胆固醇基团为柔性囊泡膜的形成提供手性中心和亲脂性区域。该构建模块自组装成具有激子科顿效应和CPL的囊泡。实现了CPL在10 - 2数量级的高不对称g因子。在紫外光照射下，科顿效应增强，g因子升高3倍，而CPL不对称因子表现出抗光照射性。将疏水性荧光染料（尼罗红）负载到囊泡膜中，以实现能量转移和手性转移，从而产生具有高g因子的红色CPL，同时在负载荧光染料后，囊泡对紫外光照射的抗性增强。这项研究突出了具有非侵入性刺激响应手性光学性质的手性囊泡系统的制备，这可能为在水性介质中制备智能手性光学材料提供新思路。
