THE HUMAN EYE: STRUCTURE, NANOTECHNOLOGY BASED DRUG DELIVERY SYSTEMS.

The intricate anatomy and physiology of the human eye make it difficult formedications to reach their intended ophthalmic regions. Ensuring appropriate ocularpenetration and prolonging the period of pharmaceutical residency is their difficultresponsibility. However, the distribution of therapeutic molecules into the ocular tissuesis hampered by a number of structural and physiological limitations, making the properdelivery of drugs to the eye through this pathway a significant challenge. Thus, visionand quality of life are profoundly damaged by ocular disorders. Effective medicinedistribution is limited by a number of ocular obstacles. These days, nanotechnologybased carriers are intriguing due to their capacity to trap hydrophilic and lipophilic drugs,enhance ocular permeability, increase bioavailability, prolong residence time, andenhance medication stability. The issues with traditional ocular dose forms have beenshown to be successfully addressed by nanocarriers. For better penetration and efficienttargeted drug administration to different ocular sites, a variety of nanocarriers such asnanodispersion systems, nanomicelles, lipidic nanocarriers, polymeric nanoparticles,liposomes, niosomes, and dendrimers, have been studied. The architecture of the eye,various ocular conditions, and difficulties with ocular delivery are all attempted to beclarified in this overview. Additionally, it examines the benefits and limitations ofvarious ocular routes of administration, importance of nanomedicine in ocular drugdelivery systems and callenges in nano-based drug delivery systems for eye illnesses.