GSH-NSs preferentially enter and accumulate in cancer cells compared to normal cells. Cells were plated on sterile coverslips and then incubated with increasing concentrations of C-6-GSH-NSs for the indicate time points. C-6-GSH-NSs exhibit an intrinsic green fluorescence and share with the RV-GSH-NSs the same methods of synthesis and the same dimensions. So, internalization and intracellular distribution of C-6-GSH-NSs can be assumed similar to those of RV-GSH-NSs. Cell internalization studies were performed on normal fibroblasts (A), on two ovarian cancer models, OVCAR3 cells (B) and SKOV3 cells (C), on a non-tumorigenic breast model, MCF10A (D) and a breast cancer cell line, MDAMB231 (E).