A supramolecular hydrogel eye-drop alleviates inflammation via clathrin-mediated endocytosis

The modulation of inflammation is effective to treat many ocular surface diseases. Thus the low bioavailability of common anti-inflammatory eye-drops urges the development of ocular drug delivery systems to extend the ocular retention and enhance the cellular uptake for improving anti-inflammatory effect of eye-drops. Here we covalently conjugate two molecules of clinically anti-inflammatory drug (i.e., dexamethasone) with a small peptide (i.e., Tyr-Glu-Asn-Pro-Thr-Tyr) to generate an anti-inflammatory hydrogel eye-drop. With a self-assembled ability, the designed supramolecular hydrogel achieves gel-sol-gel transition by varying shearing forces which increases the pre-corneal retention of drug. The fluorescent imaging reveals the efficient cellular uptake of designed conjugate via clathrin-mediated endocytosis. A rodent model of endotoxin-induced uveitis verifies that the supramolecular hydrogel eye-drop suppresses inflammation responses without ocular irritation. As a rational approach to design anti-inflammatory drugs as eye-drops, this work overcomes the frequent instillation of clinical eye-drops and further improves the bioavailability of anti-inflammatory drugs, which may provide an effective and household way to fight ocular surface inflammation.