A Photostable AIE Luminogen for Specific Mitochondrial Imaging and Tracking

Abstract

Tracking the dynamics of mitochondrial morphology has attracted much research interest because of its involvement in early stage apoptosis and degenerative conditions. To follow this process, highly specific and photostable fluorescent probes are in demand. Commercially available mitochondria trackers, however, suffer from poor photostability. To overcome this limitation, we have designed and synthesized a fluorescent agent, tetraphenylethene-triphenylphosphonium (TPE-TPP), for mitochondrial imaging. Inherent from the mitochondrial-targeting ability of TPP groups and the aggregation-induced emission (AIE) characteristics of the TPE core, TPE-TPP possesses high specificity to mitochondria, superior photostability, and appreciable tolerance to environmental change, allowing imaging and tracking of the mitochondrial morphological changes in a long period of time.

Mitochondria-Localized Fluorescent BODIPY-Platinum Conjugate

“…CCCP is an uncoupler that causes rapid acidification of the mitochondria and dysfunction of ATP synthase resulting in the decrease of the mitochondrial ΔΨ m . 33 As shown in Figure 3a, when the cells were treated with 20 μM CCCP, weaker mitochondria colocalization was observed, and the cellular uptake of BODIPY-Pt was reduced after CCCP treatment (Figure 3b). This result indicates BODIPY-Pt localizes in mitochondria and its cellular uptake is sensitive to the mitochondrial membrane potential.…”

Long-term two-photon neuroimaging with a photostable AIE luminogen

“…Cell-culture products, unless otherwise mentioned, were purchased from Invitrogen Gibco. TPE-TPP was synthesized following our previous work [23].…”

“…In addition, due to the AIE feature, TPE-TPP nanoaggregates emitted brighter fluorescence than its single molecule state under two-photon excitation. Photobleaching resistance is one of the most important advantages of AIE luminogens [19][20][21], and previously we have proved this feature of TPE-TPP nanoaggregates under one-photon excitation [23]. Herein, we studied the photostability of TPE-TPP under two-photon excitation, by utilizing a 740 nm-fs laser.…”

“…Tetraphenylethene-triphenylphosphonium (TPE-TPP) is an AIE-active luminogen, which has been used for specific mitochondrial imaging and tracking in our previous study [23]. In this paper, we found TPE-TPP can specifically stain primary neurons in vitro, as well as brain-microglia in vivo.…”

Enabling the Triplet of Tetraphenylethene to Sensitize the Excited State of Europium(III) for Protein Detection and Time‐Resolved Luminescence Imaging

“…However, in the case of living tissue or organism imaging, the in situ separation of unbound probes may be undesirable, difficult, or even impossible 16. In addition, this time‐consuming process delays the acquisition of microscopic data and prevents the monitoring of molecular interactions in real time 17. Therefore, it is highly demanding to design turn‐on luminescent probes with a high on/off ratio that may enable real‐time detection and achieve high‐contrast imaging.…”