Recent Advances in Hypoxia-Overcoming Strategy of Aggregation-Induced Emission Photosensitizers for Efficient Photodynamic Therapy.

Abstract

Hypoxia is an inherent physiologic barrier in the microenvironment of solid tumor and has badly restricted the therapeutic effect of photodynamic therapy (PDT). Meanwhile, the photosensitizers (PSs) agents used for PDT applications regularly encounter the tiresome aggregation-caused quenching effect that seriously decreases the production efficiency of cytotoxic reactive oxygen species. The aggregation-induced emission (AIE) PSs with anti-quenching characteristics in the aggregate state have been considered as a promising tool for achieving highly efficient PDT applications, and plenty of studies have widely demonstrated their advantages in various diseases. Herein, this review summarizes the recent progress of AIE PSs in the battle of antitumor hypoxia issue and highlights the practical molecular principles of hypoxia-overcoming AIE PSs. According to the hypoxia-overcoming mechanism, these representative cases are divided into low O2 -dependent (type I PDT) and O2 -dependent tactics (mainly including O2 -enrichment type II PDT and combination therapy). Furthermore, the underlying challenges and prospects of AIE PSs in hypoxia-overcoming PDT were proposed and thus expect to promote the next development of AIE PSs. This article is protected by copyright. All rights reserved.