Carbon dots of different composition and surface functionalization: cytotoxicity issues relevant to fluorescence cell imaging.
Nanoscale carbon particles have emerged as versatile precursors for a new class of highly fluorescent nanomaterials that resemble semiconductor quantum dots. The surface-passivated fluorescent carbon nanoparticles, dubbed 'carbon dots', were already demonstrated for their potential optical bioimaging applications in vitro and in vivo. In this study, we conducted a systematic cytotoxicity evaluation on the carbon dots prepared by various combinations of precursor carbon nanoparticles and molecules for the particle surface functionalization. The results suggested that the cytotoxicity of carbon dots was dependent on the selection of surface passivation molecules. Those dots showing more significant cytotoxicity at higher concentrations were also evaluated for their effects on the fluorescence imaging of live cells. The implications of the results on the eventual use of carbon dots as cell imaging agents are discussed.
Department of Chemistry and Laboratory for Emerging Materials and Technology, Clemson University, Clemson, SC 29634-0973,  USA.
Yanli
Y
Wang
Parambath
P
Anilkumar
Li
L
Cao
Jia-Hui
JH
Liu
Pengju G
PG
Luo
Kenneth N
KN
Tackett
Sushant
S
Sahu
Ping
P
Wang
Xin
X
Wang
Ya-Ping
YP
Sun
D000818:Animals; D002244:Carbon / Q000737:chemistry*; D002460:Cell Line; D005453:Fluorescence; D019073:HT29 Cells; D006801:Humans; D051379:Mice; D008856:Microscopy, Fluorescence / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D045663:Quantum Dots; D013499:Surface Properties; D018675:Toxicity Tests
D002244:Carbon