Red AIE Luminogens with Tunable Organelle Specific Anchoring for Live Cell Dynamic Super Resolution Imaging

Abstract

Lysosomes and mitochondria play an important role in maintaining cell homeostasis. Visualizing the long‐term activities of lysosomes and mitochondria on the nanometer scale in live cells is essential for further understanding their functions but remains challenging due to the limitations of existing fluorescent probes, such as aggregation‐caused quenching (ACQ) effect, limited signal‐to‐noise ratio from fluorescence “always on” in the process of targeting organelle and poor photobleaching resistance. Herein, two efficient red‐emitting aggregation‐induced emission (AIE) luminogens are reported, which showed “off‐on” fluorescence characteristic and specific lysosomes as well as mitochondria targeting capability. Owing to their AIE characteristics, a Stokes’ shift larger than 100 nm, good biocompatibility, and excellent photostability, the AIE luminogens have been successfully utilized for high fidelity imaging of lysosomes and mitochondria. By virtue of these two probes, stimulated emission depletion (STED) images of dynamic lysosomal fusion and mitochondrial fission with a high resolution of 65.6 nm are obtained. Furthermore, the interactions between lysosomes and mitochondria in the process of mitophagy are recorded. This study also provides practical guidance for designing specific organelle targeting probes to support live cell dynamic super‐resolution imaging.

Facilely prepared aggregation-induced emission (AIE) nanocrystals with deep-red emission for super-resolution imaging

“…22 On the other hand, organic fluorophores with “aggregation-induced emission (AIE)” features were also prepared and used as efficient STED imaging agents due to their highly emissive characteristics in aggregates and impressive photo-stability. 23,24 According to the two considerations, AIE NPs or AIE dots could provide the chance to well meet the requirements in STED nanoscopy. 22,25–28 However, it should be mentioned that for AIE dots, although intramolecular motions can be restricted to some extent, kinetically controlled nanoprecipitation usually produced amorphous particles.…”

Bleaching‐Resistant Super‐Resolution Fluorescence Microscopy

“…As a result, such AIE nanoparticles are excellent candidates for long-term STED imaging (Figure 4I). [109][110][111]201] These nanoparticles still have several disadvantages, such as their relatively large sizes versus organic dyes, the requirement for surface modification for labeling, and biocompatibility. Despite such disadvantages, nanoparticles are rapidly emerging as promising probes for SRM due to their strong resistance to bleaching.…”

“…As a result, such AIE nanoparticles are excellent candidates for long‐term STED imaging (Figure 4I ). [ 109 , 110 , 111 , 201 ]…”

Design and structural regulation of AIE photosensitizers for imaging-guided photodynamic anti-tumor application

“…In addition, most AIE PSs have higher light stability and great resistance to chemical degradation and are more suitable for long-term cancer cell tracking and treatment, while improving the signal-to-noise ratio of bioimaging. [47][48][49][50] The typical AIE core structures reported consist of tetraphenylethylene (TPE), boron-dipyrromethene derivatives (BODIPY) and triphenylamine (TPA). The classical TPE core structure has four freely rotating phenyl groups which give the molecule a large Stokes shift and bright blue fluorescence emission.…”