Targeted photodynamic therapy using a water-soluble aggregation-Induced emission photosensitizer activated by an acidic tumor microenvironment

Aggregation-induced emission (AIE)-active photosensitizers (PSs) are considered as a kind of promising functionalized materials for photodynamic therapy of tumor. Improving the targeted ability of water-soluble AIE PSs capable of minimizing the inadvertent activation is of great significance but remains a challenging task. Herein, we report an effective synthetic strategy for preparing water-soluble AIE photosensitizer (termed WAPS) with high targeted capacity mediated by supramolecular assembly. The pillar[5]arene (WP5) can bind WAPS through host-guest interaction in neutral aqueous solution, resulting in a large change in donor-acceptor structure of WAPS and a weak photodynamic activity. Notably, the binding interface of WAPS and WP5 shifts under an acidic environment (pH 5.2), permitting the reversible control of singlet oxygen (O-1(2)) generation and photodynamic targeting of cancer cells in cultured and tumor-bearing mice. This work provides an ingenious way to prepare water-soluble AIE PS with high selectivity for tumor treatment.

Automated summary

This study presents an effective synthetic strategy for preparing water-soluble AIE photosensitizers with high targeted capacity mediated by supramolecular assembly. The reversible control of singlet oxygen generation and photodynamic targeting of cancer cells in an acidic environment is achieved.