Photocatalytic activity of biogenic zinc oxide nanoparticles: In vitro antimicrobial, biocompatibility, and molecular docking studies

Abstract

The biogenic synthesis of zinc oxide nanoparticles (ZnO NPs) with pinecone extract (PCE) as a reducing agent and antibacterial agent was explored. The current study aims to investigate the biosynthesis of ZnO NPs and their effect on photocatalytic dye degradation and antimicrobial properties. The physical, chemical, and morphological properties of biogenic ZnO NPs synthesized using PCE were investigated using advanced spectroscopy techniques such as Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy, transmission electron microscopy (TEM) analysis, selected area electron diffraction (SAED), and X-ray diffraction (XRD) techniques. The photocatalytic degradation of methylene blue was measured spectrophotometrically using biogenic ZnO NPs as nanocatalysts, and decolonization of solution indicates dye degradation gradually as exposure duration increases. The antimicrobial properties of ZnONPs against the tested pathogenic strains were demonstrated using the disc diffusion method. The antimicrobial efficacy of ZnONPs was further explained using molecular docking analysis. Confirmation of the lowest binding energy was used to predict receptor binding site with NPs in order to understand the mechanistic approach. ZnONPs are likely to interact with pathogens via mechanical enfolding, which could be one of the major toxicity actions of ZnONPs against strains. Furthermore, the nontoxicity and biocompatibility of ZnO NPs were studied, revealing impressive hemocompatibility with red blood cells (RBCs) and no significant toxicity to Brine shrimps at lower ZnONP concentrations.

Keywords

• biogenic synthesis
• pinecone extract
• photocatalytic degradation
• antimicrobial activity
• docking