▎ 摘　　要

In this research, we have covalently functionalized graphene oxide (GO) with hydrophilic and biocompatible Pluronic F38 (F38), Tween 80 (T80) and maltodextrin (MD) for loading and delivery of a poorly water soluble antioxidant and anticancer drug, ellagic acid (EA). The functionalized GO showed a good aqueous solubility and biocompatibility. This is the first time that the EA was loaded onto GO-F38, GO-T80 and GO-MD through pi-pi interactions, yielding a loading capacity of 1 g, 1.22 g and 1.14 g of EA per gram of GO-F38, GO-T80, and GO-MD respectively. Their capabilities to kill human breast carcinoma cells (MCF7) and human colon adenocarcinoma cells (HT29) were then investigated. The release of EA from these nanocarriers was studied in water (neutral pH) and buffer solutions of pH 4 and 10 at 37 degrees C. The GO-F38, GO-T80 and GO-MD released similar to 36-38% drug within 3 days at pH 10. The cytotoxicity of EA loaded onto the functionalized GO was higher than that of free EA dissolved in DMSO. The DPPH assay was used to study the antioxidant activity, and the very similar antioxidant activities were obtained for three EA-loaded nanocarriers and the free EA, indicating that loading of EA onto the functionalized GO did not hamper its antioxidant activity. Therefore, all three functionalized GOs are suitable nanocarriers for drug delivery because of their non-toxicity and high drug loading capacity.