Ultrahigh Supramolecular Cascaded Room‐Temperature Phosphorescence Capturing System

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 (ϕET) 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. An ultrahigh supramolecular cascaded RTP‐capturing system was constructed based on a multivalent supramolecular aggregate using cucurbit[7]uril (CB[7]) and sulfonatocalix[4]arene (SC4AD) in aqueous medium. Energy transfer from G⊂CB[7]@SC4AD to primary (RhB or DBT) and then to secondary energy acceptors (Cy5 or NiB) gives rise to long‐range and long‐lived photoluminescence, especially NIR delayed emission (675 nm).