We present a novel ligand, 5‐norbornene‐2‐nonanoic acid, which can be directly added during established quantum dot (QD) syntheses in organic solvents to generate “clickable” QDs at a few hundred nmol scale. This ligand has a carboxyl group at one terminus to bind to the surface of QDs and a norbornene group at the opposite end that enables straightforward phase transfer of QDs into aqueous solutions via efficient norbornene/tetrazine click chemistry. Our ligand system removes the traditional ligand‐exchange step and can produce water‐soluble QDs with a high quantum yield and a small hydrodynamic diameter of approximately 12 nm at an order of magnitude higher scale than previous methods. We demonstrate the effectiveness of our approach by incubating azido‐functionalized CdSe/CdS QDs with 4T1 cancer cells that are metabolically labeled with a dibenzocyclooctyne‐bearing unnatural sugar. The QDs exhibit high targeting efficiency and minimal nonspecific binding.

中文翻译：

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通过点击化学灵活地功能化量子点的配体系统

我们提出了一种新型的配体5-降冰片烯2-壬酸，可以在有机溶剂中建立的量子点（QD）合成过程中直接添加该配体，以产生几百nmol规模的“可点击的” QD。该配体在一个末端具有一个羧基以结合到QD的表面，而在另一端具有一个降冰片烯基，从而可以通过有效的降冰片烯/四嗪点击化学将QD直接相转移到水溶液中。我们的配体系统消除了传统的配体交换步骤，可以生产水溶性量子点，量子点产率高，流体动力学直径小，约为12 nm，规模比以前的方法高出一个数量级。我们通过将叠氮基官能化的CdSe / CdS QD与4T1癌细胞一起孵育来证明我们的方法的有效性，这些癌细胞被带有二苯并环辛炔的非天然糖代谢标记。量子点表现出高靶向效率和最小的非特异性结合。