Near-infrared (NIR) fluorescence imaging is a noninvasive technique that provides numerous advantages for the real-time in vivo monitoring of biological information in living subjects without the use of ionizing radiation. Near-infrared fluorescent (NIRF) dyes are widely used as fluorescent imaging probes. These fluorescent dyes remarkably decrease the interference caused by the self-absorption of substances and autofluorescence, increase detection selectivity and sensitivity, and reduce damage to the human body. Thus, they are beneficial for bioassays. Indole heptamethine cyanine dyes are widely investigated in the field of near-infrared fluorescence imaging. They are mainly composed of indole heterocyclics, heptamethine chains, and N-substituent side chains. With indole heptamethine cyanine dyes as the parent, introducing reactive groups to the parent compounds or changing their structures can make fluorescent probes have different functions like labeling protein and tumor, detecting intracellular metal cations, which has become the hotspot in the field of fluorescence imaging of biological research. Therefore, this study reviewed the applications of indole heptamethine cyanine fluorescent probes to metal cation detection, pH, molecules, tumor imaging, and protein in vivo. The distribution, imaging results, and metabolism of the probes in vivo and in vitro were described. The biological application trends and existing problems of fluorescent probes were discussed.

中文翻译：

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基于吲哚七次甲基花青染料的近红外荧光探针体内外研究进展


近红外 (NIR) 荧光成像是一种无创技术，无需使用电离辐射即可实时体内监测活体生物信息，具有众多优势。近红外荧光（NIRF）染料广泛用作荧光成像探针。这些荧光染料显着减少了物质的自吸收和自发荧光造成的干扰，提高了检测的选择性和灵敏度，减少了对人体的伤害。因此，它们有利于生物测定。吲哚七次甲基花青染料在近红外荧光成像领域被广泛研究。它们主要由吲哚杂环、七次甲基链和N-取代基侧链组成。以吲哚七次甲基花青染料为母体，在母体化合物中引入反应基团或改变其结构，可以使荧光探针具有标记蛋白质和肿瘤、检测细胞内金属阳离子等不同功能，已成为荧光成像领域的热点。生物学研究。因此，本研究综述了吲哚七次甲基花青荧光探针在金属阳离子检测、pH、分子、肿瘤成像和体内蛋白质等方面的应用。描述了探针在体内和体外的分布、成像结果和代谢。讨论了荧光探针的生物学应用趋势和存在的问题。