Inflammation is a complex physiological response involving various cellular and molecular events. Sulfur dioxide (SO₂), which is usually in the form of HSO₃⁻ and SO₃²⁻ under physiological conditions, plays a crucial role in the regulation of inflammation and diseases. Frequency upconversion luminescence (FUCL) can realize the unique anti-Stokes process of long-wavelength excitation to short-wavelength emission; thus, it is a highly promising optical method for in vivo imaging due to its deep tissue penetration, low photo-damage, etc. Therefore, we developed a near-infrared FUCL NIRX-1 probe for the detection of HSO₃⁻. NIRX-1 had a fast response (80 s), a low detection limit (0.43 μM), and high selectivity towards HSO₃⁻. In addition, NIRX-1 had deep light penetration ability due to the near-infrared excitation at 808 nm and was able to detect HSO₃⁻ in living cells and mice. Lastly, NIRX-1 was employed in the imaging of HSO₃⁻ in an inflammation mouse model through FUCL imaging techniques. All these features make NIRX-1 a good candidate for the investigation of SO₂-associated physiological and pathological processes.

中文翻译：

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一种用于快速、灵敏目视检测二氧化硫的近红外频率上转换荧光探针


炎症是一种复杂的生理反应，涉及各种细胞和分子事件。二氧化硫 （SO₂） 在生理条件下通常以 HSO₃⁻ 和 SO₃²⁻ 的形式存在，在炎症和疾病的调节中起着至关重要的作用。频率上转换发光 （FUCL） 可以实现独特的长波长激发到短波长发射的反斯托克斯过程;因此，由于其深层组织穿透性、低光损伤等，它是一种非常有前途的体内成像光学方法。因此，我们开发了一种用于检测 HSO₃ ^- 的近红外 FUCL NIRX-1 探针。NIRX-1 具有快速响应 （80 s）、低检测限 （0.43 μM） 和对 HSO₃⁻ 的高选择性。此外，由于 808 nm 的近红外激发，NIRX-1 具有深光穿透能力，并且能够检测活细胞和小鼠中的 HSO₃⁻。最后，通过 FUCL 成像技术，将 NIRX-1 用于炎症小鼠模型中 HSO₃⁻ 的成像。所有这些特征使 NIRX-1 成为研究 SO₂ 相关生理和病理过程的良好候选者。