MOE Key Laboratory for Analytical Science of Food Safety and Biology, College of Chemistry, Fuzhou University, Fuzhou 350108, China.
School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457, Singapore.
Nano Lett. 2021 Mar 24;21(6):2625-2633. doi: 10.1021/acs.nanolett.1c00197. Epub 2021 Mar 8.
Silver sulfide (AgS) has gained widespread attention in second near-infrared (950-1700 nm, NIR-II) window imaging because of its high fluorescence quantum yield and low toxicity. However, its "always on" fluorescence shows inapplicability for targeted molecule-activated biomedical applications. Herein, we first developed a novel silver/silver sulfide Janus nanoparticle (Ag/AgS JNP) for specific activatable fluorescence imaging in the NIR-II window. Inner-particle electron compensation from Ag to AgS upon laser irradiation endowed JNPs an "off" state of fluorescence, whereas the oxidization of Ag incubated with HO, decreasing the electron-transfer effect and illuminating the NIR-II fluorescence of the AgS part. In contrast, the absorption of Ag/AgS JNPs slightly decreased in an HO-dependent manner, showing an activated photoacoustic imaging mechanism. The Ag/AgS JNPs were used for noninvasive location and diagnosis of diseases , such as for liver injury and cancer, with high sensitivity and accuracy.
硫化银（AgS）由于其高荧光量子产率和低毒性，在近红外二区（950-1700nm，NIR-II）成像中得到了广泛关注。然而，其“常开”荧光使其不适用于靶向分子激活的生物医学应用。在此，我们首次开发了一种新型的银/硫化银 Janus 纳米粒子（Ag/AgS JNP），用于在近红外二区进行特定的可激活荧光成像。激光照射下，Ag 向 AgS 的内粒子电子补偿赋予了 JNP 荧光的“关闭”状态，而与 HO 孵育的 Ag 会降低电子转移效应，并照亮 AgS 部分的近红外二区荧光。相比之下，Ag/AgS JNPs 的吸收在 HO 依赖性方式下略有降低，显示出激活的光声成像机制。Ag/AgS JNPs 可用于非侵入性定位和疾病诊断，例如肝损伤和癌症，具有高灵敏度和准确性。
