Nanoparticle-mediated targeted delivery of lutein for retinal protection: emerging strategies in ocular drug targeting.

Lutein, a key macular carotenoid with potent antioxidant and blue-light-filtering properties, plays a crucial role in maintaining retinal integrity and preventing vision-threatening ocular disorders. However, its clinical efficacy is limited by poor aqueous solubility, instability, low bioavailability, and restricted penetration across ocular barriers. Recent advances in nanotechnology have enabled the development of lutein-loaded nanoparticle systems that significantly improve its stability, solubility, controlled release, and targeted delivery to anterior and posterior eye segments. This review comprehensively summarizes the physicochemical properties of lutein and the limitations of conventional lutein supplementation. The review entails diverse nanocarrier platforms including liposomes, polymeric nanoparticles, solid lipid nanoparticles, nanoemulsions, micelles, and cubosomes highlights their mechanisms of ocular transport, formulation variables, and therapeutic relevance. Emerging evidence demonstrates that lutein-loaded nanoparticles unveil enhanced antioxidant, anti-inflammatory, anti-angiogenic, and cytoprotective effects across multiple ocular pathologies such as age-related macular degeneration, cataract, dry eye disease, blue light-induced retinal degeneration, and retinal pigment epithelial cell injury. Preclinical studies reveal improved retinal uptake, prolonged retention, and superior biological activity compared to free lutein. The lutein-loaded nanoparticles represent a promising next-generation strategy for efficient ocular delivery and targeted management of degenerative and oxidative eye diseases.