Near-infrared afterglow materials, which can significantly reduce background fluorescence and improve penetration in living organisms, are vital for precision imaging. However, the practicability of near-infrared afterglow materials has been hindered by their short lifetime and low luminescence quantum efficiency. Herein, we propose an effective strategy for doping water-soluble afterglow polymer host materials with fluorescent dyes, leveraging the step-by-step Förster energy transfer principle to realize near-infrared afterglow. Benefiting from the ultralong lifetime of 4.2 s and high quantum efficiency of 20.1 % for the blue host PAMCz as well as efficient cascade energy transfer efficiency of 83.3 %, the developed NIR afterglow exhibits luminescence peaked at 750 nm, a lifetime of 1.4 s, and a quantum efficiency of 17.1 %. A successful demonstration of near-infrared afterglow biological imaging with a penetration depth of 3.4 mm and signal-to-background ratio of 48.3, has been established. These advancements expand the scope of near-infrared afterglow materials by combining an ultralong lifetime with high quantum efficiency, providing a roadmap for designing robust near-infrared materials.

中文翻译：

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通过级联能量传递实现稳定的近红外余辉聚合物


近红外余辉材料可以显著降低背景荧光并提高对生物体的渗透性，对于精确成像至关重要。然而，近红外余辉材料的实用性一直受到其寿命短和发光量子效率低的阻碍。在此，我们提出了一种用荧光染料掺杂水溶性余辉聚合物主体材料的有效策略，利用逐步的 Förster 能量转移原理实现近红外余辉。得益于蓝色主机 PAMCz 的 4.2 秒超长寿命和 20.1% 的高量子效率以及 83.3% 的高效级联能量传输效率，开发的近红外余辉的发光峰值为 750 nm，寿命为 1.4 秒，量子效率为 17.1%。已经成功建立了穿透深度为 3.4 mm、信噪比为 48.3 的近红外余辉生物成像示范。这些进步通过将超长寿命与高量子效率相结合，扩大了近红外余辉材料的范围，为设计稳健的近红外材料提供了路线图。