Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing, 210023, China.
Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing, 210023, China; State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, China.
Biochem Biophys Res Commun. 2020 Sep 3;529(4):930-935. doi: 10.1016/j.bbrc.2020.06.072. Epub 2020 Jul 30.
With significantly decreased light scattering and tissue autofluorescence, fluorescence imaging in the second near infrared (NIR-II, 1000-1700 nm) region has been heavily explored in biomedical field recently. Silver sulfide quantum dots (AgS QDs) with unique optical properties were one of the most classic NIR-II imaging probes. However, the AgS QDs for in vivo purpose were mainly obtain by oil phase-based high-temperature route at present. Here, we proposed a mild aqueous route to prepare NIR-II emissive AgS QDs for in vivo tumor imaging. Original AgS QDs was obtained by mixing sodium sulfide and silver nitrate in a thiol-terminated polyethylene glycol (mPEG-SH) solution. Treating the original AgS QDs with extra mPEG-SH ligands produced highly PEGyalted AgS QDs. These re-PEGylated AgS QDs exhibited much better blood circulation and tumor accumulation in vivo comparing with the original ones, which can serve as excellent tumor imaging probes. The whole-body blood vessel imaging of living mice was achieved with high resolution, the bio-distribution of these QDs were studied by NIR-II imaging as well. This work also highlighted the importance of ligand density for tumor targeting.
具有显著降低的光散射和组织自发荧光，近红外二区（NIR-II，1000-1700nm）的荧光成像是最近生物医学领域的研究热点。具有独特光学性质的硫化银量子点（AgS QDs）是最经典的 NIR-II 成像探针之一。然而，目前用于体内目的的 AgS QDs 主要是通过基于油相的高温路线获得的。在这里，我们提出了一种温和的水相路线来制备用于体内肿瘤成像的近红外二区发射 AgS QDs。原始的 AgS QDs 通过在巯基封端的聚乙二醇（mPEG-SH）溶液中混合硫化钠和硝酸银来获得。用额外的 mPEG-SH 配体处理原始 AgS QDs 会产生高度 PEGylated AgS QDs。与原始 AgS QDs 相比，这些再 PEGylated AgS QDs 在体内具有更好的血液循环和肿瘤积累，可作为优秀的肿瘤成像探针。通过高分辨率实现了活体小鼠的全身血管成像，并通过 NIR-II 成像研究了这些 QDs 的生物分布。这项工作还强调了配体密度对肿瘤靶向的重要性。
