Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics , Hunan Normal University , Changsha 410081 , P.R. China.
Department of Applied Physics , The Hong Kong Polytechnic University , Kowloon 999077 , Hong Kong , China.
ACS Appl Mater Interfaces. 2019 Feb 6;11(5):4737-4744. doi: 10.1021/acsami.8b14877. Epub 2019 Jan 28.
Carbon dots (CDs) with low biotoxicity, high photostability, and well-controlled size are highly desirable imaging agents for optical bioimaging. However, most of the CDs triggered by ultraviolet/blue light present visible/first near-infrared emissions shorter than 820 nm, impairing their imaging applications in vivo by low penetration depth. Hence, developing novel CD-based materials with second near-infrared (NIR-II) emission located in 1000-1700 nm region is an urgent task. Here, a novel NIR-II-emitting CD-based nanoprobe triggered by 808 nm laser is developed. The designed CDs with 900-1200 nm luminescence possess high quantum yield (QY-0.4%) and high biocompatibility, which have proven to be effective probes for in vivo NIR-II bioimaging. Notably, nearly 65% CDs are excreted from mouse urine within 6 h, demonstrating the rapid renal clearance of CDs. Furthermore, the designed CDs also exhibit high photothermal efficiency (30.6%), making them ideal materials for thermal ablation of cancer. Our findings pave the way of designing a multifunctional CD-based theranostic platform for simultaneously integrating the advanced NIR-II bioimaging and photothermal therapy of cancer.
碳点（CDs）具有低生物毒性、高光稳定性和可控制的尺寸，是用于光学生物成像的理想成像剂。然而，大多数由紫外/蓝光触发的 CDs 呈现出短于 820nm 的可见/近红外第一发射，这通过低穿透深度损害了它们在体内的成像应用。因此，开发具有位于 1000-1700nm 区域的新型近红外二区（NIR-II）发射的基于 CD 的材料是一项紧迫的任务。在这里，开发了一种由 808nm 激光触发的新型 NIR-II 发射 CD 基纳米探针。设计的具有 900-1200nm 发光的 CDs 具有高量子产率（QY-0.4%）和高生物相容性，已被证明是用于体内近红外二区生物成像的有效探针。值得注意的是，近 65%的 CDs 在 6 小时内从小鼠尿液中排出，表明 CDs 的快速肾清除率。此外，设计的 CDs 还表现出高的光热效率（30.6%），使其成为癌症光热治疗的理想材料。我们的研究结果为设计多功能基于 CD 的治疗诊断平台铺平了道路，该平台可同时集成先进的近红外二区生物成像和癌症光热治疗。
