Gold Nanoparticles Loaded with Chitosan Encapsulate Donepezil as a Novel Nanocomposite for Alzheimer's Disease Therapy

Alzheimer's disease (AD) is the most common cause of dementia worldwide. Fifty million people today are affected by this disease globally. AD has had a tremendous impact on the affected individual, caregiver, and society, in both developed and developing nations. Donepezil—chitosan-gold nanocomposite (Donz-CS-AuNPs) was prepared by co-precipitation technique. Placket-Burman experimental design was used in this work to estimate the effect of the three independent variables (concentration of chitosan, gold, and donepezil) on the dependent variables (loading efficiency, and particle size) by using Minitab 18.1 software. The quantities for the independent variables used were: 10 and 40 mg of donepezil, 24.6 and 73.8 mg of gold, and 500 and 1500 mg of chitosan. The Donz-CS-AuNPs were characterized using energy dispersive X-ray (EDX) analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and release study. The results of EDX showed strong signals of Au (1.5–2, 2–2.5 and 9.5–10 keV), which confirmed the specific gold peaks from the Donz-CS-AuNPs. The XRD pattern of Donz-CS-AuNPs nanocomposites showed the existence of AuNPs peak at 2θ= 38.2°, 43.8° and 64.5°. The SEM images demonstrated spherical shapes of the AuNPs. In the in vitro release study, the release increased steeply and reached 75% after 1440 min.

Keywords:
Gold nanoparticles; Alzheimer's disease; Donepezil; Controlled release