Green Catalysis Center of Zhengzhou University, College of Chemistry, Henan Joint International Research Laboratory of Green Construction of Functional Molecules and Their Bioanalytical Applications, Zhengzhou Key Laboratory of Functional Nanomaterial and Medical Theranostic, Zhengzhou University, Zhengzhou, China.
Ministry of Agriculture and Rural Affairs, Hunan Division GRG Metrol & Test, Key Laboratory Southern Farmland Pollution Prevention & Control, Changsha, Hunan, China.
Luminescence. 2021 Nov;36(7):1592-1599. doi: 10.1002/bio.4062. Epub 2021 Jul 4.
A novel nitrogen-doped graphene quantum dots (N-GQDs) with a green fluorescence emission was synthesized through microwave method using citric acid and semicarbazide hydrochloride as reactants. The as-synthesized N-GQDs exhibited good stability, excellent water solubility, and negligible cytotoxicity. Due to intermolecular charge transfer, ferric ion (Fe ) has a strong quenching effect on the N-GQDs. Fluorescence quenching has a linear relationship with the Fe concentration in the range 0.02-12 μM. The detection limit was 1.43 nM. What is more, it is worth mentioning that the obtained N-GQDs showed high selectivity and sensitivity towards Fe . Under the optimum conditions, the addition of 10-fold copper ions and 100-fold other metal ions had no influence on the detection of Fe (0.8 μM), which indicated a higher sensitivity compared with that of the reported methods. Due to their excellent properties, the obtained N-GQDs was successfully applied for sensing and imaging Fe in water samples and HeLa cells.
一种新型氮掺杂石墨烯量子点（N-GQDs）具有绿色荧光发射，通过微波法使用柠檬酸和氨基脲盐酸盐作为反应物合成。所合成的 N-GQDs 表现出良好的稳定性、优异的水溶性和可忽略的细胞毒性。由于分子间电荷转移，铁离子（Fe ）对 N-GQDs 具有很强的猝灭作用。荧光猝灭与 0.02-12 μM 范围内的 Fe 浓度呈线性关系。检测限为 1.43 nM。更值得一提的是，所得到的 N-GQDs 对 Fe 表现出高选择性和灵敏度。在最佳条件下，加入 10 倍的铜离子和 100 倍的其他金属离子对 Fe 的检测（0.8 μM）没有影响，这表明其灵敏度高于已报道的方法。由于其优异的性能，所得到的 N-GQDs 成功地应用于水样和 HeLa 细胞中 Fe 的传感和成像。
