Chitosan-based Nanomedicine in the Management of Age-related Macular Degeneration: A Review

Age-related macular degeneration (AMD) is a leading cause of permanent blindness globally. Due to the various obstacles, highly invasive intravitreal (IVT) injections are the prima-ry method used to deliver medications to the tissues of the posterior eye. An utmost patient-friendly topical ocular delivery approach has been extensively researched in recent years. Muco-adhesive compositions extend precorneal residence time while reducing precorneal clearance. They increase the likelihood of adhesion to corneal and conjunctival surfaces and, as a result, al-low for enhanced delivery to the posterior eye segment. Due to its remarkable mucoadhesive characteristics, chitosan (CS) has undergone the most extensive research of any mucoadhesive polymer. Drug delivery to the front and back of the eye is still difficult. The pharmaceutical in-dustry has shown greater interest in drug delivery systems (DDSs) based on nanotechnology (NT) in recent years, particularly those made from natural polymers like chitosan, alginate, etc. Be-cause of their incredible adaptability, higher biological effects, and favourable physicochemical properties, CS-oriented nanomaterials (NMs) are explored by researchers as prospective nanocar-riers. CS are the right substrates to develop pharmaceutical products, such as hydrogels, nanopar-ticles (NP), microparticles, and nanofibers, whether used alone or in composite form. CS-based nanocarriers deliver medicine, such as peptides, growth factors, vaccines, and genetic materials in regulated and targeted form. This review highlights current developments and challenges in chi-tosan-mediated nano therapies associated with AMD.