Gold decorated shape-tailored zinc oxide-rGO nanohybrids: Candidate for pathogenic microbe destruction and hazardous dye degradation

This work explores noble metal coupled carbon-based nanohybrid materials specifically for their antibacterial and photo-disinfection capabilities from a broader perspective of health to clean. Using gold (Au) nanoparticles (NPs) on the surface of two different shaped zinc oxide-graphene (ZnO-rGO) nanohybrids such as flake and spherical, this experiment aims to manage a pathogen-free environment while filtering and recycling carcinogenic dye-containing wastewater. The shape-tailored ZnO-rGO-Au hybrid generate a substantial amount of reactive oxygen species; ROSs: hydroxyl radical (center dot OH), superoxide (center dot O2-), singlet oxygen, and (1O2) and focal electrostatic interactions on (gram-negative Escherichia coli and gram-positive Staphylococcus aureus) bacterial cell membranes. Redox cycling and strong potential binding tendency rapture the structural organization of cells that is clearly reflected in growth kinetics, (3(4, 5-dimethylthiazol-2-yl)-2), 5-diphenyl tetrazolium bromide (MTT), inner permeable/ protein/ malondialdehyde assay, and microscopical images after the morphology dependent physical as well as the chemical effects of nanocomposites. The minimum bactericidal concentration (MBC) or minimum inhibitory concentration (MIC) studies show the Au/rGO-ZnO system to be the very potent antibacterial agent, and that only 0.18 mg/ml represents significant bactericidal activity while their toxicity towards mammalian cells is very low (>2 mg/ml). Furthermore, Au NPs alter the bandgap energy of Au/rGOZnO hybrids, causing the formation of ROSs at different pH levels or dosages of the catalyst, which results in excellent photocatalytic activity (96% degradation of Rhodamine B when using 0.75 mg catalyst). Based on a Pseudo-first-order kinetic model, a likely mechanistic pathway towards exceptional dye decomposition has also been identified.

Automated summary

This study explores the use of noble metal coupled carbon-based nanohybrid materials for antibacterial and photo-disinfection applications. The results demonstrate excellent antibacterial activity and low toxicity towards mammalian cells of the gold nanoparticles coated on zinc oxide-graphene nanohybrids.