Graphene oxide and oxidized carbon nanodiscs as biomedical scaffolds for the targeted delivery of quercetin to cancer cells.

Targeting cancer cells without affecting normal cells poses a particular challenge. Nevertheless, the utilization of innovative nanomaterials in targeted cancer therapy has witnessed significant growth in recent years. In this study, we examined two layered carbon nanomaterials, graphene and carbon nanodiscs (CNDs), both of which possess extraordinary physicochemical and structural properties alongside their nano-scale dimensions, and explored their potential as nanocarriers for quercetin, a bioactive flavonoid known for its potent anticancer properties. Within both graphitic allotropes, oxidation results in heightened hydrophilicity and the incorporation of oxygen functionalities. These factors are of great significance for drug delivery purposes. The successful oxidation and interaction of quercetin with both graphene (GO) and CNDs (oxCNDs) have been confirmed through a range of characterization techniques, including FTIR, Raman, and XPS spectroscopy, as well as XRD and AFM. In vitro anticancer tests were conducted on both normal (NIH/3T3) and glioblastoma (U87) cells. The results revealed that the bonding of quercetin with GO and oxCNDs enhances its cytotoxic effect on cancer cells. GO-Quercetin and oxCNDs-Quercetin induced G0/G1 cell cycle arrest in U87 cells, whereas oxCNDs caused G2/M arrest, indicating a distinct mode of action. In long-term survival studies, cancer cells exhibited significantly lower viability than normal cells at all corresponding doses of GO-Quercetin and oxCNDs-Quercetin. This work leads us to conclude that the conjugation of quercetin to GO and oxCNDs shows promising potential for targeted anticancer activity. However, further research at the molecular level is necessary to substantiate our preliminary findings.