Facile Synthesis and Surface Characterization of ZnO-Fe₃O₄ Metal Nanoparticles Composite Using Cow Urine from the Bos Taurus Breed and Its Applications

The key aim of the proposed research was to investigate a sustainable method for synthesizing zinc oxide nanoparticles, iron oxide nanoparticles, and a zinc-iron nanoparticle composite from the urine of Bos taurus cattle, with a focus on evaluating their medicinal properties. The synthesis of these nanoparticles was achieved through environmentally friendly processes. The synthesized nanoparticles underwent comprehensive characterization employing UV/VIS spectroscopy, particle size distribution analysis, FTIR, XRD spectra, SEM, and zeta potential analysis. The FTIR spectra validated the bioreduction of the nanoparticles and composite by revealing distinctive peaks corresponding to Fe²⁺ and Zn³⁺ ions, present in both the individual nanoparticles and the composite. Investigative results indicated that the zinc oxide nanoparticles, iron oxide nanoparticles, and the zinc-iron nanoparticle composite derived from cow urine exhibited irregular morphology, with average sizes measured at approximately 420.7 ± 99.9, 200.7 ± 60.0, and 247.7 ± 27.9 nm, respectively. The cytotoxicity assay results demonstrated that the ZnO-Fe₃O₄NPs composite exhibited a cell inhibition rate of 56.51 ± 1.0452% at a concentration of 100 µg mL⁻¹, with an IC₅₀ value of 30.69. Notably, the ZnO-Fe₃O₄NPs composite demonstrated substantial anti-inflammatory activity with a percentage inhibition of 85.52%. The biologically synthesized zinc oxide nanoparticles, iron oxide nanoparticles, and the zinc-iron nanoparticle composite displayed promising anticancer and anti-inflammatory effects without showing any indications of toxicity. The heightened biological activity observed can be attributed to their unique nanoscale characteristics, including reduced polydispersity and smaller average particle size, which improve responsiveness and interactions with biological entities. Consequently, the nanoparticle composite synthesized via this biogenic technique utilizing cow urine holds considerable potential for various pharmaceutical applications.