COMPARISON OF ZINC SALTS AND SURFACTANTS IN THE COPRECIPITATION SYNTHESIS OF ZNO NANOPARTICLES FOR PHOTODYNAMIC THERAPY APPLICATIONS

Photodynamic therapy (PDT) has emerged as an effective and promising strategy  for treating various diseases, particularly tumors, due to its localized action and reduced systemic side effects [1]. Among the different types of photosensitizers, zinc oxide  nanoparticles (ZnO-NPs) have stood out for their capacity  to produce reactive oxygen species (ROS) and their favorable optical properties [2]. In this study, we report the synthesis and characterization of ZnO-NPs using different precursors, such as zinc acetate and zinc nitrate, as well as functionalizing agents  including polyethylene glycol (PEG-6000), polyvinylpyrrolidone (PVP), and cetyltrimethylammonium bromide (CTAB). The nanoparticles were synthesized via the coprecipitation method, followed by surface functionalization to enhance  colloidal stability and biocompatibility. Characterization techniques included  X-ray diffraction (XRD), Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), diffuse reflectance UV-Vis (DRS-UV-Vis), zeta potential analysis, and dynamic light scattering (DLS). The ZnO NPs synthesized with the surfactant NaOH, especially using zinc nitrate, showed optimized ROS generation under UV irradiation and achieved 100% methylene blue photodegradation within 90 minutes, indicating their potential for use in photodynamic cancer therapy. At this stage, the main goal is to evaluate which zinc precursor and functionalizing agent combination offers the best performance as a photosensitizer for future biomedical applications.