Labeling agents with radioisotopes or fluorescent dyes are useful for investigating the biodistributions of biologically active proteins and peptides. Compared with molecular imaging with a single modality, dual imaging probes provide complementary information for each modality. The development of a dual radioisotope/fluorescence agent for protein labeling would thus be valuable for both preclinical and clinical applications. In this study, we designed and synthesized a radioiodinated BODIPY derivative (BODIPY-ML) with a maleimide group as a thiol labeling agent. In the presence of N-chlorosuccinimide and 1% acetic acid, [125 I]BODIPY-ML was successfully obtained at a radiochemical yield of 42%. In conjugation studies, model proteins including RGD peptides and anti-HER2 VHH were successfully labeled with BODIPY-ML via covalent bonds. The results demonstrated the feasibility of the radioiodinated BODIPY as a dual labeling agent via thiol groups.

中文翻译：

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作为硫醇标记剂的放射性碘化 BODIPY 衍生物的合成和评价

带有放射性同位素或荧光染料的标记剂可用于研究生物活性蛋白质和肽的生物分布。与使用单一模态的分子成像相比，双成像探针可为每种模态提供补充信息。因此，用于蛋白质标记的双放射性同位素/荧光剂的开发对于临床前和临床应用都是有价值的。在这项研究中，我们设计并合成了一种带有马来酰亚胺基团作为硫醇标记剂的放射性碘化 BODIPY 衍生物 (BODIPY-ML)。在 N-氯琥珀酰亚胺和 1% 乙酸的存在下，[125 I]BODIPY-ML 以 42% 的放射化学产率成功获得。在缀合研究中，包括 RGD 肽和抗 HER2 VHH 在内的模型蛋白通过共价键被 BODIPY-ML 成功标记。