Genotoxicity assessment of mesoporous silica and graphene oxide in GDL1 cells

Nanomaterials such as mesoporous silica and graphene oxide are increasingly used in industrial, medical, and cosmetic applications due to their unique physical and chemical properties. However, their potential genotoxicity remains poorly understood. To evaluate the associated health risks of mesoporous silica and graphene oxide, we assessed their cytotoxicity and genotoxicity in GDL1 cells using trypan blue exclusion and gpt mutation assays, followed by mutation frequency and spectrum analysis through gpt gene sequencing.

A 24-hour exposure of mesoporous silica to GDL1 cells induced dose-dependent reductions in cell viability, as well as dose-dependent increases in gpt mutation frequencies at 0.06 and 0.09 mg/mL. Graphene oxide induced cytotoxicity at higher concentrations (0.2 and 0.4 mg/mL) and significantly increased gpt mutation frequency in the highest concentration exposure group compared to controls. Mutation spectrum analysis revealed a significant increase in G: C to A: T transitions in both the exposed groups. In addition, exposure to mesoporous silica significantly increased G: C to T: A transversions, while graphene oxide exposure significantly increased G: C to C: G transversions. Mutation hotspots at positions 64, 164, and 416 in the gpt gene were identified exclusively in the mesoporous silica-treated group, indicating material-specific mutagenesis. Mutations at position 401 were detected exclusively in the graphene oxide group, indicating this site as a potential mutation hotspot.

These results demonstrate that both mesoporous silica and graphene oxide exhibit cytotoxic and genotoxic potential in vitro. The mutation patterns suggest that oxidative DNA damage, as well as inflammation associated with oxidative stress, may contribute to the observed mutagenicity. The findings reported here provide valuable insights into the molecular mechanisms underlying the mutagenicity induced by these nanomaterials and contribute to the assessment of potential human health risks.