The evolution of super-resolution imaging techniques is benefited from the ongoing competition for optimal rhodamine fluorophores. Yet, it seems blinded to select the best one among different rhodamine derivatives for specific labeling and imaging, without the knowledge on imaging impact of even the minimum structural transform. Herein, we have designed a pair of self-blinking sulforhodamines (STMR, SRhB) with the bare distinction of methyl or ethyl substituents, and engineered them with Halo protein ligands. Although the two present similar spectral properties (λab, λfl, ϕ, etc.), they demonstrated unique single-molecule characteristics preferring to individual imaging applications. Experimentally, STMR with high emissive rates was qualified for imaging structures with rapid dynamics (endoplasmic reticulum, mitochondria), and SRhB with prolonged on-times and photostability was suited for relatively "static" nuclei and microtubules. Utilized this new knowledge, the mitochondrial morphology during apoptosis and ferroptosis was first super-resolved by STMR. Our study highlights the significance of even the smallest structural modification to the modulation of super-resolution imaging performance, and would provide insight for future fluorophore design.

中文翻译：

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微妙的结构翻译显着调节自闪烁罗丹明的超分辨率成像

超分辨率成像技术的发展得益于对最佳罗丹明荧光团的持续竞争。然而，似乎盲目地从不同的罗丹明衍生物中选择最好的一种来进行特定的标记和成像，而没有了解即使是最小的结构变换对成像的影响。在此，我们设计了一对自闪烁磺酰罗丹明（STMR、SRhB），仅区分甲基或乙基取代基，并用 Halo 蛋白配体对其进行改造。尽管两者具有相似的光谱特性（λab、λfl、φ 等），但它们表现出独特的单分子特性，更适合单独的成像应用。在实验上，具有高发射率的 STMR 有资格对具有快速动力学的结构（内质网、线粒体）进行成像，SRhB 具有延长的开启时间和光稳定性，适用于相对“静态”的细胞核和微管。利用这一新知识，细胞凋亡和铁死亡过程中的线粒体形态首先被 STMR 超分辨。我们的研究强调了即使是最小的结构修改对超分辨率成像性能调制的重要性，并将为未来的荧光团设计提供见解。