Mitophagy, the process in which cells degrade dysfunctional organelles and recycle their nutrient substances by lysosomes, plays a vital role in cell metabolism and physiology. Herein, we present a highly targeting and near-infrared (NIR) mitochondrion fluorescent probe, which can monitor the process of autophagy. The response mechanism of the probe is based on intramolecular charge transfer (ICT) for the detection of autophagy and real-time imaging of living cells. We designed a primary amine as a pH sensitizing group, and due to the ICT process, the probe exhibits green fluorescence, and when it is protonated the ICT process is broken, and the NIR fluorescence will be restored. Simultaneously, the green fluorescence of the probe disappears. This probe exhibits excellent selectivity, high sensitivity and clean responsiveness, which indicate that it can be applied for high-targeting and high-sensitive imaging of the process of autophagy in living systems.

中文翻译：

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基于ICT的近红外荧光探针，用于监测活细胞中的线粒体。

线粒体吞噬是细胞降解功能紊乱的细胞器并通过溶酶体循环利用其营养物质的过程，在细胞代谢和生理学中起着至关重要的作用。在这里，我们提出了一种高度靶向和近红外（NIR）线粒体荧光探针，它可以监测自噬的过程。探针的响应机制基于分子内电荷转移（ICT），可检测活细胞的自噬和实时成像。我们设计了伯胺作为pH敏化基团，由于ICT过程，该探针显示绿色荧光，当质子化时，ICT过程破裂，NIR荧光将恢复。同时，探针的绿色荧光消失。该探针具有出色的选择性，高灵敏度和干净的响应性，