title: Solid-phase synthesis of highly fluorescent nitrogen-doped carbon dots for sensitive and selective probing ferric ions in living cells.
abstract: Carbon quantum dots (C-Dots) have drawn extensive attention in recent years due to their stable physicochemical and photochemical properties. However, the development of nitrogen-doped carbon quantum dots (N-doped C-Dots) is still on its early stage. In this paper, a facile and high-output solid-phase synthesis approach was proposed for the fabrication of N-doped, highly fluorescent carbon quantum dots. The obtained N-doped C-Dots exhibited a strong blue emission with an absolute quantum yield (QY) of up to 31%, owing to fluorescence enhancement effect of introduced N atoms into carbon dots. The strong coordination of oxygen-rich groups on N-doped C-Dots to Fe(3+) caused fluorescence quenching via nonradiative electron-transfer, leading to the quantitative detection of Fe(3+). The probe exhibited a wide linear response concentration range (0.01-500 μM) to Fe(3+) with a detection limit of 2.5 nM. Significantly, the N-doped C-Dots possess negligible cytotoxicity, excellent biocompatibility, and high photostability. All these features are favorable for label-free monitoring of Fe(3+) in complex biological samples. It was then successfully applied for the fluorescence imaging of intracellular Fe(3+). As an efficient chemosensor, the N-doped C-Dots hold great promise to broaden applications in biological systems.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, Lanzhou University , Lanzhou 730000, China.
authors.forename: Haijuan
authors.initials: H
authors.lastname: Zhang
authors.forename: Yonglei
authors.initials: Y
authors.lastname: Chen
authors.forename: Meijuan
authors.initials: M
authors.lastname: Liang
authors.forename: Laifang
authors.initials: L
authors.lastname: Xu
authors.forename: Shengda
authors.initials: S
authors.lastname: Qi
authors.forename: Hongli
authors.initials: H
authors.lastname: Chen
authors.forename: Xingguo
authors.initials: X
authors.lastname: Chen
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D056831:Coordination Complexes / Q000737:chemistry; D005453:Fluorescence; D006367:HeLa Cells; D006801:Humans; D007477:Ions; D007501:Iron / Q000032:analysis*; D057230:Limit of Detection; D057054:Molecular Imaging / Q000379:methods*; D015335:Molecular Probes / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D009584:Nitrogen / Q000737:chemistry*; D045663:Quantum Dots; D060327:Solid-Phase Synthesis Techniques
chemical_list: D056831:Coordination Complexes; D007477:Ions; D015335:Molecular Probes; D002244:Carbon; D007501:Iron; D009584:Nitrogen