Interactions between rGO/TNT nanocomposites and cells: Regulation of cell morphology, uptake, cytotoxicity, adhesion and migration

Reduced graphene oxide/titanium dioxide nanotube (rGO/TNT) composites have superior properties, such as a large surface area, extraordinary mechanical strength, high carrier mobility, etc. However, the biosafety and biocompatibility of these composites, such as their influences on cell viability and cell functions, which are of paramount importance, are still not fully addressed. In this study, rGO/TNT nanocomposites were successfully synthesized through a modified hydrothermal treatment method. Then, the interactions between the rGO/TNT nanocomposites and Raw264.7 mouse monocyte-macrophage cells were further investigated. The results show that the rGO/TNT nanocomposites could be internalized by Raw264.7 cells and mainly gathered inside the cytoplasm. No rGO/TNT nanocomposites were observed in the nucleus. Moreover, the rGO/TNT nanocomposites exhibited low cytotoxicity toward Raw264.7 cells at a lower dose, though they may exhibit cytotoxicity to some extent at very high concentrations. In addition, the uptake of the nanocomposites influenced the cell cytoskeleton organization, while the cell adhesion and migration abilities were also impaired.