College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, P. R. China.
Angew Chem Int Ed Engl. 2021 Dec 20;60(52):27171-27177. doi: 10.1002/anie.202113577. Epub 2021 Nov 18.
An ultrahigh supramolecular cascaded phosphorescence-capturing aggregate was constructed by multivalent co-assembly of cucurbit[7]uril (CB[7]) and amphipathic sulfonatocalix[4]arene (SC4AD). The initial dibromophthalimide derivative (G) generated a weak phosphorescent emission at 505 nm by host-guest interaction with CB[7], which further assembled with SC4AD to form homogeneously spherical nanoparticles with a dramatic enhancement of both phosphorescence lifetime to 1.13 ms and emission intensity by 40-fold. Notably, this G⊂CB[7]@SC4AD aggregate exhibited efficient phosphorescence energy transfer to Rhodamine B (RhB) and benzothiadiazole (DBT) with high efficiency (ϕ ) of 84.4 % and 76.3 % and an antenna effect (AE) of 289.4 and 119.5, respectively, and then each of these can function as a bridge to further transfer their energy to second near-IR acceptors Cy5 or Nile blue (NiB) to achieve cascaded phosphorescence energy transfer. The final aggregate with long-range effect from 425 nm to 800 nm and long-lived photoluminescence was further employed as an imaging agent for multicolour cell labeling.
通过葫芦[7]脲（CB[7]）和两亲性磺化杯[4]芳烃（SC4AD）的多价共组装，构建了超高分维级联上转换磷光捕获聚集物。初始二溴邻苯二甲酰亚胺衍生物（G）通过与 CB[7]的主客体相互作用产生弱磷光发射，在 505nm 处，其进一步与 SC4AD 组装形成均匀的球形纳米粒子，磷光寿命显著延长至 1.13ms，发射强度增强了 40 倍。值得注意的是，这种 G⊂CB[7]@SC4AD 聚集物表现出高效的磷光能量转移给罗丹明 B（RhB）和苯并噻二唑（DBT），效率（ϕ）分别为 84.4%和 76.3%，天线效应（AE）分别为 289.4 和 119.5，然后每个都可以作为桥梁，进一步将其能量传递给第二个近红外受体 Cy5 或尼罗蓝（NiB），以实现级联磷光能量转移。最终的聚集物具有从 425nm 到 800nm 的远程效应和长寿命光致发光，进一步用作多色细胞标记的成像剂。
