LAUSR

Abstract Aims The aim of our work is to load Vinblastine drugs loaded on graphene quantum dots to improve its cytotoxicity on cancer cells and reduce it on the normal cell in the composites. Moreover, the GQDs-Vin composite significantly inhibited tumour growth in animals. Methods GQDs-Vin composites were prepared by homogenisation of GQDs and Vin solutions. The loading of Vin on GQDs in the composites was characterised by FTIR, PL, UV-vis spectra, and TEM. The cytotoxicity of GQDs, Vin, and GQDs-Vin composites was investigated on the Hela, HGC-27, A549, MCF-7, CCF-STTG1 cells and Vero by in vitro and in vivo methods. The difference in cellular structure and organelles in mice’s livers in comparison between the control group and GQDs-Vin (1:5) groups was characterised by TEM. Results The diameter of the nanoparticles of GQDs-Vin composites in weight ratios 1:1, 1:3 and 1:5 w/w of 50–70 nm, 100–150 nm and ∼500nm, respectively, is larger than that of GQDs of 10–50nm. The in vitro results showed that GQDs not only improved the cytotoxicity of Vin to cancer cells but also decreased its cytotoxicity towards normal cells in the composites. The GQDs-Vin (1:5) composite exhibited a stronger tumour inhibition effect than Vin alone. The morphology of mice’s livers showed the absence GQDs-Vin nanoparticles in the mice livers suggesting the lack of storage and the leakage from the liver without any toxicity. Conclusions Results of the improved cytotoxicity of GQDs-Vin composite on cancer cells, its reduced cytotoxicity on normal cells and the significant inhibition on tumour growth of GQDs-Vin composite compared with Vin and GQDs alone may indicate a synergistic effect of Vin and GQDs in their composites for anticancer application.