Graphene Oxide Laser Printing for Controlled STEM Cells Differentia- tion and Antibacterial Effects

Graphene and Graphene oxide (GO) are capable of inducing stem cells differentiation into bone tissue with variable efficacy depending on reductive state of 362a Monday, February 19, 2018 the material. Thus, controlling the oxidative state of the GO it is possible, in principle, to modulate the osteogenic process and the bone mineral density distribution. In this study, we laser-printed GO surfaces in order to obtain both a local photo/thermal GO reduction and the formation of nano-wrinkles along precise geometric pattern. Calvarial-derived Mesenchimal Stem cells (CMSC) were isolated in primary culture from skull calvarial fragments and their behaviour was characterized on GO patterns. Initially, after cells adhesion on the surface, stem cells migrated and accumulated on the reduced/wrinkled surface. When the local density of the stem cells on the reduced stripes was high, cells started to proliferate and occupy the oxidized/flat area. The designed surfaces morphology guided stem cell orientation and the reduction accelerated differentiation. Furthermore, the reduced nano-wrinkles greatly inhibited the growth of S. aureus. We propose a promising laser-printing technology for tissue engineering and regenerative medicine, based on graphene to enhance cell growth and differentiation in a controlled way. We show that by adjusting the laser emission is possible to finely tune the GO reduction and shape substrate landscape to spatially control bone regeneration and microbial infection. This strategy can offer a revolution in present and future trends of medicine and surgery