Ge Haifeng, Huang Huiling, He Suanquan, Chen Kexin, Dai Manxiong, Zhang Zhipengjun, Chen Xinglong, Zhang Lemeng, Mao Guojiang, Liu Hongwen
Key Laboratory of Light Energy Conversion Materials of Hunan Province College, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, P. R. China.
Thoracic Medicine Department 1, The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University/Hunan Cancer Hospital, Changsha 410013, P. R. China.
Anal Chem. 2025 Aug 12;97(31):17111-17120. doi: 10.1021/acs.analchem.5c02897. Epub 2025 Jul 30.
Lysosomes are the key organelles in regulating cellular homeostasis, posing a significant role from basic enzyme trafficking to cell death. Existing fluorescent probes for imaging of lysosomes have limitations, such as tumor-associated false positives due to pH-dependent retention and single-channel emission properties restricting their use to either cellular or imaging. Real-time and high-fidelity visualization of lysosomal changes during ferroptosis both at cells and the tumor level presents a big challenge. To overcome these challenges, we developed , a glutathione (GSH)-activatable, lipophilic, visible/NIR-II dual-channel emission probe. It integrates (an anionic cyanine with NIR-II emission) and (a naphthalimide derivative with visible emission) via a GSH-responsive linker. Leveraging the high intracellular GSH concentration, upon GSH activation, hydrophilic and proton-combinable products and are released, enabling long-term lysosomal retention (over 24 h in cells and up to 15 days in tumor-bearing mice). Benefiting from the lysosome retention effect, we further achieved visible/NIR-II dual-channel longitudinal monitoring of lysosomal changes during erastin-induced ferroptosis, from cellular-level confocal to NIR-II imaging, revealing significant lysosomal destruction. This cross-scale functionality of greatly bridges cellular dynamics to organismal outcomes, addressing a long-standing gap in lysosomal research tools.
溶酶体是调节细胞内稳态的关键细胞器，在从基本酶运输到细胞死亡的过程中发挥着重要作用。现有的用于溶酶体成像的荧光探针存在局限性，例如由于pH依赖性滞留导致的肿瘤相关假阳性以及单通道发射特性限制了它们仅用于细胞成像或整体成像。在铁死亡过程中，在细胞和肿瘤水平实时、高保真地可视化溶酶体变化是一个巨大的挑战。为了克服这些挑战，我们开发了一种谷胱甘肽（GSH）可激活的、亲脂性的、可见光/近红外二区双通道发射探针。它通过一个GSH响应连接子整合了（一种具有近红外二区发射的阴离子花青）和（一种具有可见光发射的萘酰亚胺衍生物）。利用细胞内高浓度的GSH，在GSH激活后，释放出亲水且可与质子结合的产物和，从而实现溶酶体的长期保留（在细胞中超过24小时，在荷瘤小鼠中长达15天）。受益于溶酶体保留效应，我们进一步实现了在erastin诱导的铁死亡过程中对溶酶体变化的可见光/近红外二区双通道纵向监测，从细胞水平的共聚焦成像到近红外二区成像，揭示了显著的溶酶体破坏。这种跨尺度功能极大地将细胞动力学与生物体结果联系起来，填补了溶酶体研究工具中长期存在的空白。
