Aggregation Effect on Multiperformance Improvement in Aryl-Armed Phenazine-Based Emitters

Abstract

The concept of aggregate science was proposed to explain changes in materials performance that accompany the generation of aggregates, but aggregation-triggered multifunction improvements in a class of materials have rarely been reported. Herein, we present the first report of a new class of multifunctional aggregation-induced emission (AIE) luminogens (AIEgens) based on 5,10-diarylphenazine (DPZ) derivates with full-wavelength emission. Intriguingly, multiple properties, such as fluorescence intensity and free radical and type I reactive oxygen species (ROS) efficiencies, could be simultaneously activated from the unimolecular level to the aggregate state. The mechanisms of this multiple performance improvement are discussed in detail based on sufficient performance characterization, and some of the newly prepared AIEgens exhibited toxicity to cancer cells during photodynamic therapy. This work systematically demonstrates the positive effect of aggregation on improving multiple functions of materials, which is expected to promote the development of aggregate science theory for the design of multifunctional materials.

Molecular design of phenazine-5,10-diyl-dibenzonitriles and the impact on their thermally activated delayed fluorescence properties

“…The crystal structure of pBN was only published recently (a-polymorph, space group P2 1 , no. 4) 37 and another b-polymorph (space group P% 1, no. 2) has been determined in parallel in this work (see the ESI † for details).…”

Recent advances in type I organic photosensitizers for efficient photodynamic therapy for overcoming tumor hypoxia

“…However, it is interesting that once they gather, a variety of performance factors will be enhanced, including fluorescence and ROS free radicals generated. 148 Unfortunately, in the unfavorable microenvironment of solid tumors, a universal feature is severe O 2 shortage. Both PDT-mediated O 2 expenditure and microvascular destruction further exacerbate tumor hypoxia, which eventually leads to unsatisfactory therapeutic outcomes.…”

Tailor-Made Dynamic Fluorophores: Precise Structures Controlling the Photophysical Properties

“…Taking advantage of the facile C–N coupling reactions, longitudinal π-extension along the N–N axis of 5,10-dihydrophenazine was readily realized. Recently, Tang and co-workers reported a family of 5,10-dihydro-5,10-diarylphenazine derivatives with full-wavelength emission by altering the acceptor–donor compositions in the substituted groups . These compounds exhibit versatile properties, including enhanced fluorescence efficiency and free radical and type I reactive oxygen species from the unimolecular level to the aggregate state, and have shown good performance in biological applications, such as photodynamic therapy.…”

“…Recently, Tang and co-workers reported a family of 5,10-dihydro-5,10-diarylphenazine derivatives with full-wavelength emission by altering the acceptor−donor compositions in the substituted groups. 43 These compounds exhibit versatile properties, including enhanced fluorescence efficiency and free radical and type I reactive oxygen species from the unimolecular level to the aggregate state, and have shown good performance in biological applications, such as photodynamic therapy. These results have further demonstrated the great potential of dihydrophenazine core-based fluorophores in multifunctional materials.…”