Intracellular trafficking of different shaped oxidized carbon nanoparticles

Abstract

Oxidized carbon nanospheres (OCSs) and graphene oxide sheets (GOShs) were prepared by oxidation of graphite. Oxidized carbon nanotubes (OCTs) was synthesized from single-walled carbon nanotubes. All three shapes of oxidized carbon nanoparticles (OCNs) were used for investigation of their intracellular trafficking in human embryonic kidney cells (HEK293T), mouse macrophage cells (RAW264.7) and human liver cancer cells (HepG2). The results revealed all three shapes of OCNs were internalized into through HEK293T and RAW264.7 cells without endosomal trapping, including localization of all the three OCNs in HEK293T’s lysosome. In case of RAW264.7 cells, OCTs and GOShs were localized in lysosomes, only OCSs can escape from degradation in RAW264.7‘s lysosome. In case of HepG2 cells, the three shapes of OCNs were internalized into the cells through endocytosis, OCSs, OCTs and GOShs were localized in endosome and lysosome. Furthermore, the all three shapes of OCNs were found in golgi apparatus in HEK293T and HepG2 cells. In case of RAW264.7 cells, OCSs, OCTs and GOShs were localized in endoplasmic reticulum and golgi apparatus. In addition, comparison of different shaped OCNs revealed that OCSs was the fastest cellular internalization, OCTs was moderate and GOShs was the slowest cellular internalization. Hence, oxidized carbon nanoparticles had great potential be applied in biological and biomedical applications, including drug delivery system. Especially, OCSs was capable of the fastest cellular internalization and evasion of lysosomal degradation.