Fluorescent Zn²⁺ probes used for the quantitative analysis of labile Zn²⁺ concentration ([Zn²⁺]) in target organelles are crucial for understanding the role of Zn²⁺ in biological processes. Although several fluorescent Zn²⁺ probes have been developed to date, there is still a lack of consensus concerning the [Zn²⁺] in intracellular organelles. In this study, we describe the development of ZnDA-1H, a small-molecule fluorescent probe for Zn²⁺, which exhibits less pH sensitivity, high Zn²⁺ selectivity, and large fluorescence enhancement upon binding to Zn²⁺. Through protein labeling technology, ZnDA-1H was precisely targeted in various intracellular organelles, such as the nucleus, mitochondria, endoplasmic reticulum, and Golgi apparatus. ZnDA-1H exhibited a reversible fluorescence response toward labile Zn²⁺ in these organelles in live cells. Using this probe, the [Zn²⁺] in the Golgi apparatus was estimated to be 25 ± 1 nM, suggesting that labile Zn²⁺ plays a physiological role in the secretory pathway.

用于定量分析细胞器中不稳定的Zn ²⁺浓度（[Zn ²⁺ ]）的荧光Zn ²⁺探针对于理解Zn ²⁺在生物过程中的作用至关重要。尽管迄今为止已经开发了几种荧光Zn ²⁺探针，但是关于细胞内细胞器中的[Zn ²⁺ ]仍然缺乏共识。在这项研究中，我们描述ZnDA-1H，对于Zn组成的小分子荧光探针的开发²⁺，其表现出的pH灵敏度以下，高的Zn ²⁺的选择性，并且在结合的Zn大荧光增强²⁺。通过蛋白质标记技术，ZnDA-1H可以精确地靶向各种细胞内细胞器，例如细胞核，线粒体，内质网和高尔基体。ZnDA-1H在活细胞中的这些细胞器中对不稳定的Zn ²⁺表现出可逆的荧光响应。使用该探针，高尔基体中的[Zn ²⁺ ]估计为25±1 nM，这表明不稳定的Zn ²⁺在分泌途径中起着生理作用。