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We herein present an approach of photo‐induced disproportionation for preparation of Type‐I photodynamic agents. As a proof of concept, BODIPY‐based photosensitizers were rationally designed and prepared. The photo‐induced intermolecular electron transfer between homotypic chromophores leads to the disproportionation reaction, resulting in the formation of charged intermediates, cationic and anionic radicals. The cationic radicals efficiently oxidize the cellularimportant coenzyme, tetrahydrobiopterin (BH4), and the anionic radicals transfer electrons to oxygen to produce superoxide radicals (O2−⋅). One of our Type‐I photodynamic agents not only self‐assembles in water but also effectively targets the endoplasmic reticulum. It displayed excellent photocytotoxicity even in highly hypoxic environments (2 % O2), with a half‐maximal inhibitory concentration (IC50) of 0.96 μM, and demonstrated outstanding antitumor efficacy in murine models bearing HeLa tumors. [ABSTRACT FROM AUTHOR]

Given that Type-I photosensitizers (PSs) have hypoxia tolerance, developing general approaches to prepare Type-I PSs is of great importance, but remains a challenge. Here, we report a supramolecular strategy for the preparation of Type-I photodynamic agents, which simultaneously generate strong oxidizing cationic radicals and superoxide radicals, by introducing electron acceptors to the existing Type-II PSs. As a proof-of-concept, three electron acceptors were designed and co-assembled with a classical PS to produce quadruple hydrogen-bonded supramolecular photodynamic agents. The photo-induced electron transfer from the PS to the adjacent electron acceptor occurs efficiently, leading to the generation of a strong oxidizing PS+• and an anionic radical of the acceptor, which further transfers an electron to oxygen to form O2−•. In addition, these photodynamic agents induce direct photocatalytic oxidation of NADH with a turnover frequency as high as 53.7 min−1, which offers an oxygen-independent mechanism to damage tumors. Tumour hypoxia is a major issue for conventional photodynamic therapies, Here, the authors report on the supramolecular assembly of electron acceptors with photosensitizers which have improved reactive oxygen species production and are able to directly oxidise NHDH and demonstrate application against hypoxic tumours. [ABSTRACT FROM AUTHOR]

Developing Type‐I photosensitizers is considered as an efficient approach to overcome the deficiency of traditional photodynamic therapy (PDT) for hypoxic tumors. However, it remains a challenge to design photosensitizers for generating reactive oxygen species by the Type‐I process. Herein, we report a series of α,β‐linked BODIPY dimers and a trimer that exclusively generate superoxide radical (O2−.) by the Type‐I process upon light irradiation. The triplet formation originates from an effective excited‐state relaxation from the initially populated singlet (S1) to triplet (T1) states via an intermediate triplet (T2) state. The low reduction potential and ultralong lifetime of the T1 state facilitate the efficient generation of O2−. by inter‐molecular charge transfer to molecular oxygen. The energy gap of T1‐S0 is smaller than that between 3O2 and 1O2 thereby precluding the generation of singlet oxygen by the Type‐II process. The trimer exhibits superior PDT performance under the hypoxic environment. [ABSTRACT FROM AUTHOR]

Keywords: BODIPY; hypoxia; photodynamic therapy; photosensitizers; superoxide radical EN BODIPY hypoxia photodynamic therapy photosensitizers superoxide radical 24134 24134 1 10/27/21 20211102 NES 211102 In this Research Article, the absorption and fluorescence spectra of compound B 2 b (Figure 6 b) were incorrect. Berichtigung: BODIPY-Based Photodynamic Agents for Exclusively Generating Superoxide Radical over Singlet Oxygen BODIPY, hypoxia, photodynamic therapy, photosensitizers, superoxide radical. [Extracted from the article]

BODIPY, photodynamic therapy, photosensitizers, superoxide radical, hypoxia Corrigendum: BODIPY-Based Photodynamic Agents for Exclusively Generating Superoxide Radical over Singlet Oxygen Keywords: BODIPY; hypoxia; photodynamic therapy; photosensitizers; superoxide radical EN BODIPY hypoxia photodynamic therapy photosensitizers superoxide radical 23938 23938 1 10/27/21 20211102 NES 211102 In this Research Article, the absorption and fluorescence spectra of compound B 2 b (Figure 6 b) were incorrect. [Extracted from the article]