Light-Processed 3D Bioprinting of Symblepharon Rings Fortified with l-Ascorbic Acid for Ocular Tissue Engineering

Abstract

This study aims to develop gelatin methacryloyl (GelMA)-based symblepharon rings fortified with l-ascorbic acid (lAA), aiming for controlled release of vitamins for the treatment of the ocular surface, corneal healing, and acceleration of epithelial growth, while concurrently preventing potential inflammation. The human tears contain abundant IAA, which serves a protective role for ocular tissues. The utilization of 3D printing digital light processing technology not only navigating the manufacturing process of symblepharon rings, addressing challenges related to commercial production and expedited delivery to patients but also imparts enhanced flexibility compared to commercial products. This innovative approach also facilitates the production of rings that exhibit superior softness and are amenable to mechanical movements for ocular tissue engineering. The morphological, chemical, rheological, biological, thermal, and drug-release characteristics of 3D-printed lAA-loaded symblepharon rings are investigated. In the morphological characterization, it is observed that the rings exhibit a porous structure. In biocompatibility tests, Gelas and Gelas-low rings achieve over 75% viability. Following the cell test, scanning electron microscope images reveal fibroblasts adhering to Gelas and Gelas-low rings, spreading across their surfaces. Drug release studies conducted in phosphate-buffered saline at pH 7.4 reveal the complete release of lAA from Gelas-low within a 5-d incubation period.