Multicolor Nitrogen-Doped Carbon Dots for Live Cell Imaging.
Doping carbon dots with nitrogen atoms considerably enhances their fluorescence properties. However, the mechanism by which the carbon dots are doped is not fully understood. We developed a facile bottom-up hydrothermal carbonization (HTC) process that uses glucose and glycine as precursors for the synthesis of photoluminescent nitrogen-doped carbon dots. The as-prepared nitrogen-doped carbon dots were mono-dispersed spherical particles with a diameter of -2.8 nm. The doped nitrogen atoms assumed pyridinic type and pyrrolic type configurations to participate in the nanocrystal structure of the carbon dots. It appeared that the nitrogen doping introduces a new internal structure. The aqueous solution of nitrogen-doped carbon dots showed excitation wavelength-dependent multicolor photoluminescence. Further, these nitrogen-doped carbon dots readily entered the cytoplasm of A549 cancer cells and showed no significant cytotoxicity. The internalized nitrogen-doped carbon dots were localized to the cell membrane and cytoplasm, particularly around the nucleus. Further, the as-prepared, biocompatible, nitrogen-doped carbon dots demonstrated the potential to be used as fluorescent probes for multicolor live cell labeling, tracking, and imaging.
Fengyi
F
Du
Jianan
J
Li
Ye
Y
Hua
Miaomiao
M
Zhang
Zhou
Z
Zhou
Jing
J
Yuan
Jun
J
Wang
Wanxin
W
Peng
Li
L
Zhang
Sheng
S
Xia
Dongqing
D
Wang
Shiming
S
Yang
Wenrong
W
Xu
Aihua
A
Gong
Qixiang
Q
Shao
D002244:Carbon / Q000737:chemistry* / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D058948:Cell Tracking / Q000379:methods*; D003116:Color; D006801:Humans; D008163:Luminescent Measurements / Q000379:methods; D008422:Materials Testing; D009584:Nitrogen / Q000737:chemistry* / Q000633:toxicity; D045663:Quantum Dots / Q000737:chemistry / Q000633:toxicity; D013194:Staining and Labeling / Q000379:methods; D013499:Surface Properties; D014407:Tumor Cells, Cultured
D002244:Carbon; D009584:Nitrogen