Pro-oxidant F/ZnO quantum dots amplify oxidative stress and morphological perturbation in cancer cells

Reactive Oxygen Species (ROS) are highly reactive molecules produced during normal cellular metabolism that function as crucial signaling mediators under physiological conditions. The modulation of ROS production is proposed as a valuable strategy to enhance anticancer efficacy of targeted therapeutic strategies. Here, amphiphilic nanostructured formulations of fluorine-doped ZnO quantum dots (F/ZnO QDs) are prepared through a wet-chemistry approach and surface functionalization with oleylamine and oleic acid, exerting a high colloidal stability in aqueous media and enhanced pro-oxidant activity. Comprehensive physicochemical and functional analyses are proposed by integrating electrochemical and biological assays. Peroxide-mediated oxidative conditions are evaluated using a flexible, screen-printed electrochemical sensor fabricated on polyester, offering the advantages of miniaturization, low cost, and real-time detection. This system enables the monitoring of hydrogen peroxide oxidation, whose current response increases in the presence of amphiphiles-coated F/ZnO QDs, thus providing a direct evidence of pro-oxidant behaviour. MTT and ROS-detection assays confirm that the designed nanosystems significantly amplified oxidative stress and cell mortality upon H₂O₂ exposure. Furthermore, a morphometric analysis, enabled by Fourier ptychographic microscopy (FPM), showed statistically significant phenotypic differences between QDs-treated and control cells. This finding ultimately validates the synergistic potential of electrochemical and optical techniques for assessing oxidative stress mechanisms at the nanoscale.