Aggregation‐Induced Emission Luminogens with Photoresponsive Behaviors for Biomedical Applications

Abstract

Fluorescent biomedical materials can visualize subcellular structures and therapy processes in vivo. The aggregation-induced emission (AIE) phenomenon helps suppress the quenching effect in the aggregated state suffered by conventional fluorescent materials, thereby contributing to design strategies for fluorescent biomedical materials. Photoresponsive biomedical materials have attracted attention because of the inherent advantages of light; i.e., remote control, high spatial and temporal resolution, and environmentally friendly characteristics, and their combination with AIE facilitates development of fluorescent molecules with efficient photochemical reactions upon light irradiation. In this review, organic compounds with AIE features for biomedical applications and design strategies for photoresponsive AIE luminogens (AIEgens) are first summarized briefly. Applications are then reviewed, with the employment of photoresponsive and AIE-active molecules for photoactivation imaging, super-resolution imaging, light-induced drug delivery, photodynamic therapy with photochromic behavior, and bacterial targeting and killing being discussed at length. Finally, the future outlook for AIEgens is considered with the aim of stimulating innovative work for further development of this field.

Hydroxyl–yne click polymerization: a facile strategy toward poly(vinyl amino ether ester)s with color-tunable luminescence

“…31 Unconventional fluorescent polymers are a class of fluorescent materials that have attracted the attention of researchers, particularly with regard to their enormous potential applications in sensors, cellular imaging, and drug delivery. [32][33][34] In contrast to conventional fluorescent polymers, unconventional fluorescent polymers without any conventional chromophores have many advantages, such as facile preparation, structural stability, excellent water solubility, and good biocompatibility. 35,36 In the past few years, numerous polymers without conventional chromophores have been observed to exhibit significant intrinsic photoluminescence (PL) in the aggregate or solid state.…”

An overview on AIEgen‐decorated porphyrins: Current status and applications

“…Thus, over the last two decades, many papers have been published based on the AIEgen containing materials for solar cells, [36][37][38] organic light emitting diodes (OLEDs), [39][40][41][42] sensing applications, [43][44][45][46][47] photocatalysis, [48] and biomedical fields. [49][50][51] On the contrary, very limited papers were published based on the AIEgen-decorated porphyrins for fluorescence bioimaging, photodynamic therapy (PDT), photocatalytic hydrogen F I G U R E 1 Structures of AIEgens attached to porphyrin macrocycle evolution (PHE), solid state photoluminescence, electrochemiluminescence (ECL), and self-assembled studies. Herein, we have summarized the AIEgen-decorated porphyrins reported in the literature so far and discussed their AIE properties to further design more efficient porphyrins with AIE properties for wide applications.…”

Fluorescence-based monitoring of the pressure-induced aggregation microenvironment evolution for an AIEgen under multiple excitation channels

“…The discovery of the AIE effect has helped overcome the long-term limitation of conventional luminescent materials, thereby promoting further applications of prevailing luminescent systems 27 – 29 . Thus, systematic studies on structure-property relationships have played an irreplaceable role in the development of solid-state luminescent materials 30 , 31 .…”