Shaanxi Key Laboratory of Catalysis, School of Chemistry and Environment Science, Shaanxi University of Technology, Hanzhong, 723000, Shaanxi, China.
Mikrochim Acta. 2019 Jun 25;186(7):468. doi: 10.1007/s00604-019-3569-4.
New green-emissive carbon dots (G-CDs) are described here and shown to be viable fluorescent nanoprobes for the detection of changes in cellular pH values. By using m-phenylenediamine as the carbon source, G-CDs with an absolute quantum yield of 36% were solvothermally synthesized in the presence of strong HSO. The G-CDs have an average size of 2.3 nm and display strong fluorescence with excitation/emission peaks at 450/510 nm. The fluorescence intensity depends on the pH value in the range from 6.0 to 10.0, affording the capability for sensitive detection of intracellular pH variation. The nanosensor with excellent photostability exhibited good fluorescence reversibility in different pH solutions, and showed excellent stability against the influence of other biological species. The nanoprobe was successfully used in confocal fluorescence microscopy to determine pH values in SMMC-7721 cells. Graphical abstract Schematic presentation of green-emissive carbon dots (G-CDs) synthesized using m-phenylenediamine and sufuric acid through a solvothermal method for real-time fluorometric monitoring of intracellular pH values. Mechanism can be ascribed to PET process from the electron lone pair in amino group to the CDs.
这里描述了新的绿色发光碳点（G-CDs），并证明它们是用于检测细胞 pH 值变化的可行荧光纳米探针。通过使用间苯二胺作为碳源，在强 HSO 的存在下，通过溶剂热合成法合成了具有 36%绝对量子产率的 G-CDs。G-CDs 的平均尺寸为 2.3nm，具有激发/发射峰在 450/510nm 的强荧光。荧光强度取决于 pH 值在 6.0 到 10.0 之间的范围，从而能够灵敏地检测细胞内 pH 值的变化。具有优异光稳定性的纳米传感器在不同 pH 溶液中表现出良好的荧光可逆性，并且对其他生物物质的影响表现出优异的稳定性。该纳米探针成功用于共聚焦荧光显微镜来测定 SMMC-7721 细胞中的 pH 值。 示意图 展示了使用间苯二胺和硫酸通过溶剂热法合成的绿色发光碳点（G-CDs），用于实时荧光监测细胞内 pH 值。其机制可以归因于氨基中电子孤对到 CDs 的 PET 过程。
