RHAG and cancer: Rh2-treated GO (GO-Rh2), lysine-treated highly porous GR (GR-Lys), arginine-treated GR (GR-Arg), Rh2-treated GR-Lys (GR-Lys-Rh2), and Rh2–treated GR-Arg (GR-Arg-Rh2) were developed by Zare-Zardini et al. Interestingly, the cytotoxic activity of GR-Arg, GR-Lys, GR-Arg-Rh2, and GR-Lys-Rh2 against cancer cell lines was higher than that towards non-cancer cells (MSCs).