title: Insight into the cellular internalization and cytotoxicity of graphene quantum dots.
abstract: Graphene quantum dots (GQDs), owing to their unique morphology, ultra-small lateral sizes, and exceptional properties, hold great promise for many applications, especially in the biomedical field. In this work, the cellular internalization, distribution, and cytotoxicity of the GQDs are explored complementarily using transmission electron microscopy, confocal laser scanning microscopy, UV-vis, and fluorescence spectroscopies, and flow cytometry with human gastric cancer MGC-803 and breast cancer MCF-7 cells. It is demonstrated that the GQDs are internalized primarily through caveolae-mediated endocytosis. The effects of GQDs on the cell viability, internal cellular reactive oxygen species (ROS) level, mitochondrial membranes potential, and cell cycles show that the cytotoxicity of GQDs is lower than that of the micrometer-sized graphene oxide (GO). The low cytotoxicity and size consistence render GQDs appropriate for biomedical application.
authors.affiliation: Key Laboratory of Thin Film and Microfabrication of the Ministry of Education, Research Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China; Fax: 0086-21-34206915.
authors.forename: Congyu
authors.initials: C
authors.lastname: Wu
authors.forename: Chong
authors.initials: C
authors.lastname: Wang
authors.forename: Ting
authors.initials: T
authors.lastname: Han
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Zhou
authors.forename: Shouwu
authors.initials: S
authors.lastname: Guo
authors.forename: Jingyan
authors.initials: J
authors.lastname: Zhang
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D005260:Female; D006108:Graphite / Q000737:chemistry / Q000493:pharmacokinetics* / Q000633:toxicity*; D006801:Humans; D061986:MCF-7 Cells; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D045663:Quantum Dots / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity*; D013274:Stomach Neoplasms / Q000378:metabolism
chemical_list: D006108:Graphite
keywords: cellular internalization; cytotoxicity; distribution; graphene quantum dots