Synthesis and analysis of cerium-containing carbon quantum dots for bioimaging in vitro

The latest biomedical approaches based on the use of nanomaterials possessing luminescent properties make it possible to effectively visualize cancer cells or tissues, thus expanding diagnostic capabilities of the current bioimaging techniques. In this paper, a new scheme is proposed for the synthesis of cerium-containing carbon quantum dots (Ce-Qdots) of ultra-small size, promising for biomaging. Ce-Qdots have a high degree of biocompatibility, as well as remarkable redox activity. Cytotoxicity analysis performed using 4 human cell cultures confirmed the high degree of Ce-Qdots biocompatibility. It was shown that Ce-Qdots in concentrations up to 200 $\mu$g/ml do not have a negative effect on the metabolic, proliferative, migration and clonogenic activity of cell cultures after 24, 48 and 72 hours of coincubation. Ce-Qdots can be considered as the basis of a new theranostic agent for bioimaging and targeted delivery of biologically active substances.