Eco-friendly and facile production of antibacterial zinc oxide nanoparticles from Grewia flavescens (G. flavescens) leaf extract for biomedical applications

Herein, we present a green and facile synthesis of zin oxide nanoparticles (ZnO-NPs) from Grewia flavescens (G. flavescens). The obtained ZnO-NPs display inherent antibacterial activity and controlled drug release profile under physiological conditions. The structural and optical characteristics of ZnO-NPs are thoroughly vetted by UV–vis spectroscopy, FT-IR, DLS, XRD, HR-TEM, and TGA. The morphological studies unveil that ZnO-NPs exhibit a spherical shape with an average size of 20–30 nm. The Hemolysis analysis reveals that ZnO-NPs display excellent biocompatibility against blood/RBC cells. In addition, ZnO-NPs exhibit excellent antimicrobial activity against Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae). In addition, curcumin-loaded ZnO-NPs are formulated and characterized to explore the drug-release behavior of ZnO-NPs. The ZnO-NPs exhibit sustained drug release. Specifically, rapid drug release is observed in the first 12 h followed by prolonged drug release is detected. Curcumin-loaded ZnO-NPs show significant cytotoxicity against human neuroblastoma SK-N-SH cells even at 250 μg/mL concentration. All these favorable properties of ZnO-NPs reveal that ZnO-NPs can be potential candidates for biomedical applications. Thus, we strongly believe that our eco-friendly strategy from leaf extract would be a practical method not only to produce ZnO-NPs but also for other metal oxide nanoparticles for biomedical applications and beyond.