Synthesis, characterization, and biological applications of silver-doped zinc oxide nanoparticles

The growing resistance to existing drugs and their side effects has led to increased interest in developing alternative therapies for managing oxidative stress, hyperglycemia, arthritis, and diabetes. This study focuses on the synthesis and characterization of silver-doped zinc oxide nanoparticles (Ag–ZnO NPs) using a modified chemical co-precipitation method. The resulting nanoparticles were thoroughly characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). The research also evaluates the antioxidant properties, scavenging activity, and potential therapeutic applications of Ag–ZnO NPs in combating conditions such as Alzheimer’s disease, arthritis, and diabetes. TEM revealed quasi-spherical Ag particles doped on the surface of hexagonal wurtzite ZnO nanocrystals. The average crystallite size was estimated at 48.43 nm by XRD analysis using the Debye–Scherrer equation. The 200 μg/mL concentration of Ag–ZnO NPs exhibited the highest antioxidant activity of total antioxidant capacity (TAC, 85.30 ± 0.33 mg gallic acid/g) and iron reducing power (IRP, 65.03 ± 0.33 μg/mL). Ag–ZnO NPs demonstrated potent free radical-scavenging activity. Additionally, Ag–ZnO NPs showed potential as an anti-Alzheimer agent by inhibiting acetylcholinesterase (AChE) activity (IC 50 = 184.06 ± 0.80 μg/mL), as well as anti-arthritic effects through proteinase inhibition (IC 50 = 167.92 ± 2.50 μg/mL), and anti-diabetic activity by reducing α-amylase and α-glucosidase enzymes, with IC 50 values of 126.16 ± 1.50 μg/mL and 178.84 ± 1.30 μg/mL, respectively. These findings demonstrate that Ag–ZnO NPs display diverse properties in in vitro assays. Although preliminary and pending in vivo validation, they highlight the potential for future biomedical applications.