Selenium-Doped Carbon Quantum Dots for Free-Radical Scavenging

Feng Li, Tianyu Li, Chenxing Sun, Jiahao Xia, Yang Jiao and Huaping Xu

Angew.Chem. Int.Ed., 2017, 56, 9910–9914

Heteroatom doping is an effective way to adjust the fluorescent properties of carbon quantum dots. Howeverselenium-doped carbon dots have rarely been reported, eve though selenium has unique chemical properties such as redox-responsive properties owing to its special electronegativityHerein, a facile and high-output strategy to fabricate selenium- doped carbon quantum dots (Se-CQDs) with green fluorescence (quantum yield 7.6 %) is developed through the hydro-thermal treatment of selenocystine under mild conditionsSelenium heteroatoms endow the Se-CQDs with redox-dependent reversible fluorescence. Furthermore, free radicals such as COH can be effectively scavenged by the Se-CQDs.Once Se-CQDs are internalized into cells, harmful high levels of reactive oxygen species (ROS) in the cells are decreased. This property makes the Se-CQDs capable of protecting biosystems from oxidative stress.