Cornstarch-Derived ZnO Nanoparticles: A Promising Antimicrobial Agent Against Pseudomonas aeruginosa

Introduction: This study evaluates the antibacterial activity of zinc oxide nanoparticles dispersed in a polyvinylpyrrolidone solution (ZnO-NPs-PVP) synthesized using a green method based on corn starch. Methods: The ZnO-NPs are characterized using Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Ultraviolet-Visible Spectroscopy (UV-vis), and Dynamic Light Scattering (DLS). The antibacterial efficacy of ZnO-NPs-PVP is assessed against the Gram-negative bacterium Pseudomonas aeruginosa by evaluating reductions in cell viability. Results: FT-IR analysis reveals peaks typical of ZnO around 500 cm⁻¹, UV-vis spectroscopy shows a characteristic absorption band at 372 nm. TEM analysis indicates an average particle diameter of 23 nm, DLS reporting larger sizes (35 nm) due to the use of PVP as a dispersant. ZnO-NPs-PVP reduces bacterial viability by 3.75 log10 CFU/mL compared to the control. The antibacterial activity is concentration-dependent, with a 50% reduction in metabolic activity observed at 15 μg/mL. The SEM analysis shows the formation of pores in the bacterial cell wall, leading to intracellular component leakage and cell death. Discussion: ZnO-NPs-PVP could serve as an effective alternative to conventional antibiotics, particularly in the context of increasing antimicrobial resistance. Conclusion: The findings demonstrate that ZnO-NPs-PVP exhibits significant antibacterial activity and potential for use in antimicrobial treatments. Its ability to disrupt bacterial membranes and reduce metabolic activity suggests its utility as a promising candidate for future biomedical applications.