School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, P. R. China.
CAS Key Laboratory of Biomedical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science (CAS), Suzhou 215163, P. R. China.
Analyst. 2022 May 30;147(11):2558-2566. doi: 10.1039/d2an00325b.
Cellular imaging using carbon dots is an important research method in several fields. Herein, green-emissive carbon quantum dots (G-CDs) with a pretty high absolute quantum yield (QY) were fabricated a one-step solvothermal method by using -phenylenediamine and concentrated hydrochloric acid. G-CDs displayed strong green fluorescence with excitation/emission peaks at 460/500 nm, and their absolute quantum yield was as high as 58.65%. Further experiments suggested that the G-CDs we prepared have good solubility, excellent biocompatibility, and the capacity of rapidly imaging HeLa and 4T1 cells. Over expectations, the G-CDs could penetrate cells in only 10 s and the confocal images showed that the G-CDs could target the nucleus of cells. Moreover, by using 920 nm as the excitation wavelength, two-photon imaging has been successfully applied to 4T1 cells, overcoming the inherent limitations of single-photon imaging. The extremely high absolute quantum efficiency, ultra-fast imaging speed, and two-photon imaging capability make the G-CDs have good application potential in biomedical analysis and the clinical diagnostic field.
使用碳点进行细胞成像，是多个领域的一项重要研究方法。本文采用一步溶剂热法，以对苯二胺和浓盐酸为原料制备出了发绿光的碳量子点（G-CDs），其具有很高的量子产率（QY）。G-CDs 的荧光激发/发射峰位于 460/500nm，绝对量子产率高达 58.65%。进一步的实验表明，我们所制备的 G-CDs 具有良好的水溶性、优良的生物相容性和快速成像 HeLa 和 4T1 细胞的能力。出乎意料的是，G-CDs 仅需 10s 即可穿透细胞，共聚焦图像显示 G-CDs 能够靶向细胞的细胞核。此外，我们还成功地将 920nm 作为激发波长，应用双光子成像技术对 4T1 细胞进行成像，克服了单光子成像的固有局限性。极高的绝对量子效率、超快的成像速度和双光子成像能力，使 G-CDs 在生物医学分析和临床诊断领域具有良好的应用潜力。
