Fluorescein-Based Type I Supramolecular Photosensitizer via Induction of Charge Separation by Self-Assembly
Hajime Shigemitsu, Kei Ohkubo, Kazuhide Sato, Asuka Bunno, Tadashi Mori, Yasuko Osakada, Mamoru Fujitsuka, Toshiyuki Kida
Abstract
) via energy transfer from the triplet state. Here, we proposed a strategy to form type I supramolecular PSs (SPSs) utilizing the charge-separated state induced by self-assembly. This was demonstrated using a supramolecular assembly of fluorescein, which is a type II PS in the monomeric state; however, it changes to a type I SPS via self-assembly. The switching mechanism from type II to I via self-assembly was clarified using photophysical and electrochemical analyses, with the type I SPS exhibiting significant PDT effects on cancer cells. This study provides a promising approach for the development of type I PSs based on supramolecular assemblies.