Engineered riboflavin–cerium oxide nanoparticles for enhanced phototoxicity toward triple-negative breast cancer cells

Abstract

Cerium oxide nanoparticles (CeO<inf>2</inf> NPs) are redox-active nanomaterials with promising applications in biomedical engineering. In this study, CeO<inf>2</inf> NPs are functionalized with riboflavin to enhance cellular uptake and introduce photoresponsive properties. In vitro studies demonstrate that the resulting riboflavin-modified CeO<inf>2</inf> (Rf–CeO<inf>2</inf>) NPs exhibit low toxicity under dark conditions but exert significantly enhanced cytotoxicity against triple-negative breast cancer (TNBC) MDA-MB-231 cells upon ultraviolet (UV) irradiation. This light-triggered cytotoxic effect is attributed to the photoactive nature of riboflavin, which alters reactive oxygen species (ROS) generation upon UV exposure. Our findings highlight the potential of Rf–CeO<inf>2</inf> NPs as a selectively light-activated nanoplatform for targeted cancer therapy that integrates redox functionality and photoactivity into a single engineered nanomaterial, particularly for TNBC and other aggressive cancer subtypes.