Silver-zinc oxide nanocomposite: From synthesis to antimicrobial and anticancer properties

A green method by Verbascum speciosum was used to synthesize zinc oxide nanoparticles (ZnO NPs). ZnO NPs were coated with silver to synthesize Ag-ZnO nanocomposite (NCs). The physicochemical properties of Ag-ZnO NCs were analyzed by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential. The FTIR indicated the peak of Zn-O vibration and some hydroxyl and carboxyl groups. PXRD analyses confirmed the synthesis of ZnO NPs and Ag-ZnO NCs. Due to the size of the crystallite obtained from PXRD, solid-phase sizes (from FESEM and TEM images), and dynamic sizes from DLS, agglomeration was observed. The Ag-ZnO NCs showed a negative charge surface (-49.3 mV). Ag-ZnO NCs had a high antibacterial activity towards two most important infectious bacteria (i.e., Escherichia coli and Staphylococcus aureus) and anticancer activity against human liver-carcinoma cells (HepG2). Later, it depended on time and concentration of Ag-ZnO NCs. The cytotoxicity properties of Ag-ZnO NCs were also studied against NIH-3T3 as a normal cell, where the results verified the lower cell toxicities of nanocomposite than the HepG2.

Automated summary

The green method using Verbascum speciosum successfully synthesized Ag-ZnO nanocomposite, which was characterized for its physicochemical properties and exhibited excellent antibacterial and anticancer activities.