Green Synthesis of Novel Antimicrobial ZnO Nanorods

Abstract

Zinc oxide (ZnO) nanoparticles (NPs) are increasingly used in the diagnosis and prevention of various human infections and diseases. The multi-functional nature of these nanoparticles together with characteristics such as low toxicity and biodegradability, allow their use in a slew of products and applications ranging from biomedical, food and supplement industries, therapeutics and biosensors. ZnO exhibits biomimetic properties enabling biomedical applications, including use as alternatives to pre-existing antibiotics. This study discusses a simple, cost-effective and environmentally sustainable technique for the synthesis of crystalline ZnO nanorods from egg-white or albumin. Single phase nature of the of the engineered nanocrystals was determined using X-ray diffraction (XRD) and selected area electron diffraction (SAED) technique. The morphology of the ZnO nanorods was studied using transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). The diameter of synthesized ZnO nanorods was determined to be in the range of 20–30 nm. The crystal structure of wurtzite ZnO was discovered by the use of Raman, FTIR, while the surface area (12.8 m 2 /g) was analyzed by using Brunauer-Emmett-Teller (BET) surface area study. Both gram-positive and gram-negative bacterial strains were used to test the ZnO nanorods’ antibacterial abilities without the need of artificial UV activation. Findings showed that different disease-causing bacteria present in community and hospital settings respond differently to ZnO nanorods’ antibacterial activity. When the concentration of nanorods powder increased, the ratio of bacterial survival dropped, showing an increase in antibacterial activity. The gram-negative strain Pseudomonas aeruginosa was shown to have the maximum antibacterial activity of the ZnO nanorods as compared to other gram-negative and positive bacteria. Eco-friendly and green synthesis of ZnO NPs produce vital multifunctional nanomaterials which possess promising antibacterial properties with more extensive studies may develop drugs for multidrug resistance bacteria.