Formulation of PVA Hydrogel Patch as a Drug Delivery System of Albumin Nanoparticles Loaded with Curcumin

Curcumin is a widely researched natural molecule due to its abundance of pharmacological effects, such as antioxidant, antitumor, anti-inflammatory, etc. The main limitation of curcumin, however, is its low aqueous solubility, which worsens its biopharmaceutical characteristics. The aim of this study was to encapsulate curcumin in albumin nanoparticles and to subsequently incorporate them into a polyvinyl alcohol patch, resulting in a new drug formulation for skin application. The nanoparticles were characterized by a small mean diameter of approximately 162 nm, a narrow size distribution, and a negative zeta potential. TEM confirmed the small size of the nanoparticles. The ratio between the drug and albumin was optimized, achieving approximately 88% encapsulation efficiency. Protein-ligand docking, utilizing CB-Dock, indicated a strong interaction between curcumin and albumin. The binding between the molecules was proved via diffuse-reflectance UV-vis and XRD analyses. The encapsulated curcumin showed a significantly potentiated scavenging activity against ABTS and DPPH radicals in comparison with the pure drug, as well as a protective effect in H₂O₂-induced oxidative stress in fibroblasts. The loaded nanoparticles were further incorporated in a PVA hydrogel patch, which was characterized in terms of mechanical properties and in vitro release. Therefore, the resulting system could provide more effective skin delivery and an improved antioxidant activity of curcumin.