Abstract We report a self-assembled calcium-binding nanoprobe which emits a near-infrared fluorescence (NIRF) signal. We have designed a calcium-binding NIRF nanoprobe by chemically coupling alendronate (ALN), a specific targeting ligand, and NIRF-emitting Cy5.5-labeled dibenzocyclooctyne, to the two respective ends of azide-polyethylene glycol-NHS ester. Prepared ALN-PEG-Cy5.5 forms the self-assembled nanostructures and has high affinity for calcium phosphates-containing bone minerals. In addition, ALN-PEG-Cy5.5 can be employed to visualize intracellular calcium ion levels in vitro as well as normal bone tissues in vivo. These results suggest that our calcium-binding NIRF nanoprobe has a promising potential for calcium imaging in vitro and in vivo.

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用于骨组织成像的钙结合近红外荧光纳米探针

摘要 我们报告了一种自组装的钙结合纳米探针，它发出近红外荧光 (NIRF) 信号。我们设计了一种钙结合 NIRF 纳米探针，通过将阿仑膦酸盐 (ALN)、一种特定的靶向配体和 NIRF 发射 Cy5.5 标记的二苯并环辛炔化学偶联到叠氮化物-聚乙二醇-NHS 酯的两端。制备的 ALN-PEG-Cy5.5 形成自组装纳米结构，对含磷酸钙的骨矿物质具有高亲和力。此外，ALN-PEG-Cy5.5 可用于观察体外细胞内钙离子水平以及体内正常骨组织。这些结果表明，我们的钙结合 NIRF 纳米探针在体外和体内钙成像方面具有广阔的潜力。