In-vitro evaluation of co-excipients for release of donepezil hydrochloride from Carbopol 974P based tablets

The prime aims of the present work at formulating and preparing matrix tablets using Carbopol 974P to sustain the release of donepezil HCl. Tablets were prepared by direct compression method and evaluated for the effects of ingredients on the in-vitro release behavior. Gelatin, α-cellulose, sodium alginate, hydroxyapatite, and natural zeolite (clinoptilolite) were used as co-excipients to modulate the formulations. The prepared tablets of the 10 formulations were characterized by using Fourier transform infrared spectroscopy (FT-IR), digital microscope and scanning electron microscopy (SEM) techniques. The drug release kinetics was analyzed using Zero-order, First-order, Hixson-Crowell and Peppas models. The result indicated that the drug release rates highly depended on the polymers and pH medium. In addition, it was obtained that the combination of Carbopol 974P and gelatin retarded the drug release. So, these matrix tablets can reduce the dose intake. Thus, these matrix tablets are a promising release of donepezil HCl.