Extraction, Characterization, and Evaluation of Chia Seed Mucilage as a Natural Superdisintegrant in Donepezil Hydrochloride Fast-Dissolving Films

Abstract

Natural gums and mucilage have attracted considerable interest as multifunctional pharmaceutical excipients owing to their biocompatibility, biodegradability, and cost-effectiveness. The present study investigated the potential of Salvia hispanica (chia) seed mucilage as a natural superdisintegrant in the development of oral disintegrating films (ODFs) of Donepezil hydrochloride, an acetylcholinesterase inhibitor indicated for the management of Alzheimer's disease. Chia seed mucilage was isolated and characterized for its physicochemical properties. Donepezil hydrochloride-loaded ODFs (F1–F6) were prepared by the solvent casting method using different concentrations of chia seed mucilage. The formulations were evaluated for appearance, weight variation, thickness, folding endurance, surface pH, moisture loss, drug content, in vitro disintegration time, and in vitro dissolution. Drug–excipient compatibility was assessed by FTIR, while surface morphology was examined using scanning electron microscopy (SEM). The optimized formulation was subjected to accelerated stability studies as per ICH guidelines (40 ± 2°C/75 ± 5% RH) for 2 months. FTIR analysis confirmed the absence of significant drug–excipient interactions, while SEM revealed a rough, plate-like, and flaky surface morphology. All formulations complied with acceptable pharmacopeial limits for physicochemical characteristics, with drug content ranging from 94.2–99.2%. Film thickness varied between 50.33 and 60.41 μm, and moisture loss ranged from 2.08–3.96%. Disintegration time increased with increasing mucilage concentration and ranged from 42.1 to 59.5 s. Among all formulations, F3 demonstrated the shortest disintegration time (42.1 ± 1.14 s) and the highest cumulative drug release (99.72% within 6 min). Accelerated stability studies showed no significant changes in the physicochemical properties, drug content, disintegration time, or dissolution profile of the optimized formulation. Chia seed mucilage proved to be a promising natural superdisintegrant for the formulation of Donepezil hydrochloride oral disintegrating films. The optimized formulation (F3) exhibited rapid disintegration, excellent drug release, and satisfactory stability, highlighting its potential as an effective immediate-release oral drug delivery system for improved patient compliance.