Highly Enhanced Fluorescence of Supramolecular Polymers Based on a Cyanostilbene Derivative and Cucurbit[8]uril in Aqueous Solution

Supramolecular polymers (SPs) have received great attention because of their potential for various practical applications. As part of our search for SPs that are highly fluorescent in aqueous media, we designed a system based on a cucurbit[8]uril (CB[8]) host and a newly designed cyanostilbene guest. Fluorescence quantum yields of ≈0 % in the disassembled monomer state and 91 % in the CB[8]-induced SP state were obtained. The intriguing photophysical properties of the SP are elucidated through detailed experimental and computational analysis, paving the way towards a fascinating class of water-soluble fluorescent SPs.