Green Synthesis Of Nano-graphene And Its Toxicity Evaluation

Objective: Nano-graphene oxide was prepared and its toxicity was evaluated by in vitro and in vivo method in order to explore its potential in biomedical application.Methods: Graphene oxide, ammonia and hydrogen peroxide were taken as the raw material for the preparation of nano-graphene oxide through the hydrothermal method. The physicochemical properties were analysed by TEM, FT-IR, XPS, Laman, XRD and Zeta potential. The toxicity of nano-graphene oxide(0, 12.5, 25, 50, 100, 200 μg/m L)was measured by MTT assay in vitro. The effects of nano-graphene oxide(0, 12.5, 25, 50, 100, 200 μg/m L) on spontaneous movement, heart rate, apoptosis and the related gene expression level of cardiovascular system in zebrafish embryos and larvae were analysed with the help of zebrafish model.Results:(1) About the preparation of nano-graphene oxide, nano-graphene oxide with hydrophilic groups such as amino, carboxyl and hydroxyl, in the dimension range from 20 to 50 nm, was environmentally friendly synthesized and the yield was as high as 90%. As-prepared nano-graphene oxide with zeta potential around-30 m V showed stable dispersion in aqueous solution.(2) The in vitro toxicity experiment showed the viability of L929 cells decreased with the increase of the density of nano-graphene oxide, while the cell viability maintained 90% even at the highest concentration of 200 μg/m L.(3) The in vivo toxicity experiment demonstrated low concentration of nano-graphene oxide(12.5, 25 μg/m L) had little toxicity on Zebrafish embryos and larvae and the influence of nano-graphene oxide on spontaneous movement, heart rate, apoptosis and the related gene expression of cardiovascular system in zebrafish was negligible. With the concentration increased to 50 μg/m L, the toxicity of NGO increased in dose-dependently.Conclusion: The as-prepared nano-graphene oxide with high yield has good in vitro and in vivo compatibility, suggesting broad application prospect in biomedical area.