Graphene Oxide Immobilized PLGA-polydopamine Nanofibrous Scaffolds for Growth Inhibition of Colon Cancer Cells

Graphene oxide (GO)/poly (lactide-co-glycolic acid) (PLGA) scaffolds have promising applications in the biomedical field. However, greater attention is focused on the incorporated system and its applications in normal cells. In this work, a novel GO immobilized PLGA nanofibrous scaffold assisted by polydopamine (PLGA-PDA-GO) is developed for growth inhibition of HT-29 colon cancer cells. The interactions between GO and PDA are attributed to a pi-pi conjugate interaction and electrostatic attraction. In addition to the enhancement of thermal stability and mechanical strength, the surface roughness, hydrophilicity, and electro-activity of the scaffolds are significantly improved by immobilization of GO. The scaffolds show good inhibition of HT-29, and immobilized GO is observed to be in contact with but not internalized in HT-29 cells. The cytotoxicity mechanism of scaffolds toward HT-29 is attributed to intracellular activated reactive oxygen species that result from the physical interaction of the sharp GO edges and electrical signals of pi-pi stacking between PDA and GO.