State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China.
Nanoscale. 2017 Aug 3;9(30):10948-10960. doi: 10.1039/c7nr03658b.
We prepare for the first time a novel type of fluorescent carbon quantum dot (or carbon dot, CD) with intrinsic mitochondrial targeting ability by a one-step hydrothermal treatment of chitosan, ethylenediamine and mercaptosuccinic acid. The as-prepared CDs can realize mitochondrial imaging and mitochondria-targeted photodynamic cancer therapy without further modifications of other mitochondriotropic ligands (such as triphenylphosphine, TPP). Currently, many commercial mitochondrial probes suffer from the lack of modifiable groups, poor photostability, short tracking time, high cost and/or complicated staining procedures, which severely limit their applications in live-cell mitochondrial imaging. Compared to commercial mitochondrial probes such as MitoTrackers, our CDs exhibit remarkable features including ultra-simple and cost-effective synthesis, excellent photostability, facile storage, easy surface modification, wash-free and long-term imaging capability and negligible cytotoxicity. Besides, since mitochondria are susceptible to the reactive oxygen species generated during chemo-, photo- or radiotherapy, mitochondria-targeted cancer therapy has attracted much attention due to its satisfying anticancer efficiency. To test if the CDs can be used for mitochondria-targeted drug delivery, they were conjugated with a photosensitizer rose bengal (RB) and the resultant CDs-RB nanomissiles achieved efficient cellular uptake and mitochondrial targeting/accumulation, realizing mitochondria-targeted photodynamic therapy. We believe that the CD-based nanotheranostics holds great promise in various biomedical applications.
我们首次通过一步水热处理壳聚糖、乙二胺和巯基丁二酸，制备了具有内在线粒体靶向能力的新型荧光碳量子点（或碳点，CD）。所制备的 CDs 无需进一步修饰其他靶向线粒体的配体（如三苯基膦，TPP），即可实现线粒体成像和线粒体靶向光动力癌症治疗。目前，许多商业线粒体探针存在缺乏可修饰基团、光稳定性差、跟踪时间短、成本高和/或染色程序复杂等问题，严重限制了它们在活细胞线粒体成像中的应用。与 MitoTrackers 等商业线粒体探针相比，我们的 CDs 具有超简单、低成本、优异的光稳定性、易于储存、易于表面修饰、免洗和长期成像能力以及可忽略的细胞毒性等显著特点。此外，由于线粒体易受到化疗、光疗或放疗过程中产生的活性氧的影响，因此基于线粒体的癌症治疗因其令人满意的抗癌效率而受到广泛关注。为了测试 CD 是否可用于线粒体靶向药物传递，我们将其与光敏剂玫瑰红（RB）缀合，所得的 CDs-RB 纳米导弹实现了有效的细胞摄取和线粒体靶向/积累，实现了线粒体靶向光动力治疗。我们相信基于 CD 的纳米治疗学在各种生物医学应用中具有广阔的应用前景。
