Silk biomaterials for corneal tissue engineering: From research approaches to therapeutic potentials; A review

The corneal complications can result in opacity and eventual blindness. Furthermore, a shortage of available donors constrains the existing therapeutic options. Therefore, one of the most promising strategies involves the application of biomaterials, particularly silk. Silk has garnered significant attention among these biomaterials due to its natural origin and diverse features derived from different sources. One of the most critical factors of silk is its transparency, which is crucial for the cornea, and there are no concerns about infection. This material also possesses several advantages, including cost-effectiveness in production, biocompatibility in vivo and in vitro, biodegradation, and desirable mechanical characteristics. Modifications in the topographical structure, porosity, and crystallinity of silk enhance its properties and optimize its suitability for wound dressing, efficient drug delivery systems, and various cornea-related treatments. In each layer, silk was examined as a single biomaterial or blended with the others, so, this review aims to explore silk as a potential material for corneal regenerative medicine from a novel viewpoint. By considering a range of studies, a classification system has been developed that categorizes the utilization of silk in the various layers of the cornea and sub-categorizes the different modifications and applications of silk.