Evaluation of the anti-cancer potential of zinc oxide nanoparticles synthesized by chemical and green methods using Cucurbita pepo seed extract for photodynamic therapy

The anticancer effects of zinc oxide nanoparticles (ZnO-NPs) synthesised by biologically assisted (using Cucurbita pepo seed extract) and chemical sol-gel methods on MCF-7 cells were investigated under photodynamic therapy (PDT) with an ultraviolet (UV) light source. Ultraviolet-visible (UV–visible) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Zeta potential measurement, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) were utilized. The UV-Vis spectra of the NPs showed a surface plasmon resonance peak centred at 376 nm, while the electrostatic potential of both types of NPs showed values indicative of their high stability. SEM and XRD results revealed the spherical textured nanoparticles with large surface area (with particle sizes of ca. 35 nm and 27 nm), and a hexagonal wurtzite crystal structure. The MTT assays performed using both the NPs upon exposure to UV light indicated a concentration and time-dependent reduction in the MCF-7 cell viability in vitro . Overall, the findings have underscored ZnO-NPs as a promising and safe therapeutic alternative for breast cancer treatment, offering potential for optimised PDT protocols in clinical oncology.