A novel nature-inspired ligno-alginate hydrogel coated with Fe3O4/GO for the efficient-sustained release of levodopa

Levodopa (LD), a precursor to dopamine, is commonly used to treat Parkinson's disease. However, its oral formulations suffer from low bioavailability, toxicity, and untargeted delivery. This study aimed to develop a nature-based hydrogel for sustained LD release, addressing these limitations. The hydrogel was synthesized using sodium alginate (SAl) and lignosulfonic acid (LSA) as polymers, cross-linked with Ba 2+ ions, and coated with iron oxide nanoparticles (Fe 3 O 4 ) and graphene oxide nanoparticles (GO). The resulting ligno-alginate films were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA), and Field Emission Scanning Electron Microscopy (FESEM). In-vitro drug release was evaluated using UV–visible spectroscopy. The formulations LD 2 (SAl-LSA-GO-LD) and LD 3 (SAl-LSA-Fe 3 O 4 -GO-LD) demonstrated superior sustained release properties, attributed to the hydrophobic layer provided by GO, which controlled the swelling rate and slowed drug diffusion. LD 2 showed the highest drug loading efficiency at 69 % and a sustained release of 24 % over 48 h, which was better than previously reported work of 64 % in 30 h. Incorporating Fe 3 O 4 endowed the delivery vehicle with magnetic properties for targeted drug delivery. This study presents a novel and efficient approach for the sustained release of LD using a ligno-alginate hydrogel coated with Fe 3 O 4 and GO, offering promising potential for Parkinson's treatment.