美国密西西比大学Delcamp, Jared H.团队报道，具有短波红外吸收和发射特性的硅-RosIndolizine荧光团实现体内荧光成像。相关研究成果于2024年3月25日发表于国际顶尖学术期刊《自然—化学》。

短波红外（SWIR，1000–1700 nm）和扩展SWIR（ESWIR，1700–2700 nm）区域的体内荧光成像具有巨大的诊断成像潜力。尽管图像对比度已被证明随着更长波长的使用而提高，但在这些区域发射的有机荧光团的设计和合成是具有挑战性的。

该文中，研究人员合成了一系列硅RosIndolizine（SiRos）荧光团，其峰值发射波长为1300–1700 nm，发射起始点为1800–2200 nm。研究人员使用含时密度泛函理论对荧光团进行了光物理（稳态和时间分辨）、电化学和计算表征。使用两种荧光团（SiRos1300和SiRos1550）配制了纳米乳液，并将其用于小鼠心血管系统的全身循环SWIR荧光成像。

这些研究产生了高分辨率的SWIR图像，在整个循环系统中都可以看到清晰的血管系统。这种SiRos支架建立了产生长波长发射SWIR和ESWIR荧光团的设计原则。

附：英文原文

Title: Silicon-RosIndolizine fluorophores with shortwave infrared absorption and emission profiles enable in vivo fluorescence imaging

Author: Meador, William E., Lin, Eric Y., Lim, Irene, Friedman, Hannah C., Ndaleh, David, Shaik, Abdul K., Hammer, Nathan I., Yang, Boqian, Caram, Justin R., Sletten, Ellen M., Delcamp, Jared H.

Issue&Volume: 2024-03-25

Abstract: In vivo fluorescence imaging in the shortwave infrared (SWIR, 1,000–1,700nm) and extended SWIR (ESWIR, 1,700–2,700nm) regions has tremendous potential for diagnostic imaging. Although image contrast has been shown to improve as longer wavelengths are accessed, the design and synthesis of organic fluorophores that emit in these regions is challenging. Here we synthesize a series of silicon-RosIndolizine (SiRos) fluorophores that exhibit peak emission wavelengths from 1,300–1,700nm and emission onsets of 1,800–2,200nm. We characterize the fluorophores photophysically (both steady-state and time-resolved), electrochemically and computationally using time-dependent density functional theory. Using two of the fluorophores (SiRos1300 and SiRos1550), we formulate nanoemulsions and use them for general systemic circulatory SWIR fluorescence imaging of the cardiovascular system in mice. These studies resulted in high-resolution SWIR images with well-defined vasculature visible throughout the entire circulatory system. This SiRos scaffold establishes design principles for generating long-wavelength emitting SWIR and ESWIR fluorophores.

DOI: 10.1038/s41557-024-01464-6

Source: https://www.nature.com/articles/s41557-024-01464-6