Recently, shortwave-infrared (SWIR) fluorescence imaging for the optical diagnostics of diseases has attracted much attention as a new noninvasive imaging modality. For this application, the development of SWIR molecular imaging probes with high biocompatibility is crucial. Although many types of biocompatible SWIR fluorescent probes based on organic dyes have been reported, there are no SWIR-emitting molecular imaging probes that can be used for the detection of specific biomolecules in vivo. To apply SWIR-emitting molecular imaging probes to biomedical fields, we developed a biocompatible SWIR fluorescent dye based on π-conjugation extended indocyanine green (ICG), where ICG is the only approved near-infrared dye by the US Food and Drug Administration (FDA) for use in the clinic. Using the π-conjugation extended ICG, we prepared SWIR molecular imaging probes that can be used for in vivo tumor imaging. Herein, we demonstrate noninvasive SWIR fluorescence imaging of human epidermal growth factor receptor 2 (HER2)-positive and epidermal growth factor receptor (EGFR)-positive breast tumors using π-conjugation extended ICG and monoclonal antibody conjugates. The presented π-conjugation extended ICG analog probes will be a breakthrough to apply SWIR fluorescence imaging in biomedical fields.

中文翻译：

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基于π-共轭扩展吲哚菁绿的短波红外荧光分子成像探针

最近，用于疾病光学诊断的短波红外 (SWIR) 荧光成像作为一种新的无创成像方式引起了广泛关注。对于这种应用，开发具有高生物相容性的 SWIR 分子成像探针至关重要。尽管已经报道了许多类型的基于有机染料的生物相容性 SWIR 荧光探针，但还没有可用于检测体内特定生物分子的 SWIR 发射分子成像探针。为了将 SWIR 发射分子成像探针应用于生物医学领域，我们开发了一种基于 π 共轭扩展吲哚菁绿 (ICG) 的生物相容性 SWIR 荧光染料，其中 ICG 是美国食品和药物管理局 (FDA) 唯一批准的近红外染料) 用于临床。使用 π 共轭扩展 ICG，我们制备了可用于体内肿瘤成像的SWIR分子成像探针。在此，我们展示了使用 π 偶联扩展 ICG 和单克隆抗体偶联物对人表皮生长因子受体 2 (HER2) 阳性和表皮生长因子受体 (EGFR) 阳性乳腺肿瘤进行无创 SWIR 荧光成像。提出的 π 共轭扩展 ICG 模拟探针将是将 SWIR 荧光成像应用于生物医学领域的突破。