Delivering active molecules to the eye; the concept of electrospinning as potent tool for drug delivery systems

Ocular drug delivery is a challenging but fascinating topical route of administration. Although the eye is easily accessible to common drug formulations such as drops, its complex structure presents main obstacles to successfully deliver drugs. Low ocular bioavailability due to pre-corneal fluid and gravity drainage limits the efficacy of the products. Therefore, researchers have proposed various drug delivery systems synthesized by biomaterials, mostly polymers, which can deliver active ingredients to the ocular surface and remain for longer period. Such systems as electrospun fibrous structures resembling the extracellular matrix can embed various therapeutic molecules aiming to target eye diseases. The electrospun matrices, which can be used as inserts or implants, offer biocompatibility, biodegradability, and good mechanical properties. At the same time, they can be molded into different shapes and textures, significant features for ocular delivery. Over the last decades, the electrospinning process has offered many advancements in tissue engineering and drug delivery fields; however, the clinical translation of the electrospun fibrous matrices is still in the embryonic stages. This review article focuses on the recent therapeutic applications of ocular fibrous systems as potent drug delivery tools. In addition, authors have categorized the electrospun matrices according to the target eye disease, such as glaucoma, ocular infections, and other eye diseases.