Biosynthesis of sulfur quantum dots and cerium oxide nanoparticles for bioimaging and reactive oxygen species modulation in Y79 retinoblastoma cancer cells.

Abstract

Introduction: Retinoblastoma is considered a common cancer in early childhood with a poor prognosis, and innovative strategies for early diagnosis and treatment are essential. The use of nanoparticles is one of the most efficient approaches among these strategies.

Methods: Sulfur quantum dots (SQDs) and cerium oxide nanoparticles (CeO₂) were synthesized through simple and eco-friendly green synthesis method using Arabic gum and an extract from Okra (Abelmoschus esculentus) fruit, respectively. Then, the nanoparticles were characterized using UV-Vis, PL, FTIR, XRD, FESEM/TEM, and XPS techniques. The cytotoxicity, Annexin V-FITC apoptosis assay, and measurement of reactive oxygen species along with cellular uptake, were evaluated.

Results: The results of characterization confirmed the successful synthesis of SQDs and CeO₂ with a crystalline nature and the average size of 4.79 and 27.31 nm, respectively. The findings indicated that SQDs had no significant inhibitory effect on normal and cancer cells. The cell uptake of SQDs demonstrated high internalization into Y79 cells with an exited green light color under a fluorescent microscope. On the other hand, CeO₂ nanoparticles showed the ability to suppress the growth and increase early and late apoptosis of Y79 cells at concentrations of 500 μg/mL after 24 h. The level of reactive oxygen species (ROS) was also increased in Y79 cells after treatment with CeO₂.

Conclusion: As the SQDs exhibited green light color and CeO₂ enhanced apoptosis and ROS levels, this study suggested SQDs could be a potential bioimaging and labeling agent, while CeO₂ may be considered for therapeutic applications in retinoblastoma.