Fu YuJia, Guo XiaoFeng, Wang Hong
Hebei Key Laboratory of Heterocyclic Compounds, Handan University, Hebei Center for New Inorganic Optoelectronic Nanomaterial Research, Handan University, Handan, 056005, China.
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Anal Methods. 2025 Jul 3;17(26):5372-5382. doi: 10.1039/d5ay00757g.
The design strategy of targeted fluorescent probes usually involves modifying the probes with organelle-targeting groups, which then guide the probes to enter specific organelles by the traction of the targeting groups. However, the targeting ability of subcellular localization groups is not perfect, and the target analytes are not specifically distributed within the cells. Therefore, designing novel molecular fluorescent probes for highly specific and selective detection of target analytes within specific organelles is an important research direction that deserves attention. Although multiple high-efficiency lysosomal localization fluorescent probes for HS have been developed, the pH range for the fluorescence response of these probes to HS does not match the specific acidic range of the lysosome very well. In this work, by analyzing the relationship between the structures of the pH-responsive groups and the response range, excellent acidic pH-activated lysosome-localized fluorescent probes Lyso-NP-DS and Lyso-NP-NBD with a better performance have been developed. After the reaction with HS, the fluorescence activation pH ranges of their derivatives were between 2.5 and 5.5, 3.0 and 5.5, respectively. However, this could not only solve the problem of insufficient matching between the pH activation range for the fluorescence response to HS and the specific acidic range within the lysosome, but it also shows the characteristics of two-photon excitation and high sensitivity. This effectively avoids the background interference and extracellular fluorescence interference in the lysosome, and an accurate and efficient detection of HS within the lysosome is achieved.
靶向荧光探针的设计策略通常包括用细胞器靶向基团修饰探针，然后在靶向基团的牵引下引导探针进入特定的细胞器。然而，亚细胞定位基团的靶向能力并不完美，目标分析物在细胞内并非特异性分布。因此，设计用于在特定细胞器内高度特异性和选择性检测目标分析物的新型分子荧光探针是一个值得关注的重要研究方向。尽管已经开发了多种用于检测硫化氢（HS）的高效溶酶体定位荧光探针，但这些探针对HS的荧光响应pH范围与溶酶体的特定酸性范围不太匹配。在这项工作中，通过分析pH响应基团的结构与响应范围之间的关系，开发了性能更好的优异酸性pH激活的溶酶体定位荧光探针Lyso-NP-DS和Lyso-NP-NBD。与HS反应后，它们衍生物的荧光激活pH范围分别在2.5至5.5、3.0至5.5之间。然而，这不仅解决了对HS的荧光响应pH激活范围与溶酶体内特定酸性范围匹配不足的问题，还表现出双光子激发和高灵敏度的特性。这有效地避免了溶酶体中的背景干扰和细胞外荧光干扰，并实现了对溶酶体内HS的准确高效检测。
