Bioinspired Fibrillary Hydrogel with Controlled Swelling Behavior: Applicability as an Artificial Vitreous

Area of Science:

• Ophthalmology
• Biomaterials Science
• Polymer Chemistry

Background:

• The natural vitreous humor comprises fibrillary collagen and hyaluronic acid (HA).
• Mimicking this composition is key for developing effective vitreous substitutes.
• Previous work established a two-component hydrogel system for this purpose.

Purpose of the Study:

• To optimize and evaluate novel injectable hydrogels as potential vitreous humor replacements.
• To assess the biocompatibility and functional performance of these hydrogels in vivo.
• To investigate the swelling behavior of hydrogels in relation to native vitreous properties.

Main Methods:

• Synthesized and characterized 11 formulations of a two-component hydrogel (gellan and poly[methacrylamide-co-(methacrylic acid)]).
• Evaluated hydrogel properties (optical, physical, mechanical, transport) against native vitreous standards.
• Assessed biocompatibility, intraocular pressure, retinal function (electroretinography), and optical clarity in rabbit models over 30 days.

Main Results:

• Two optimized hydrogel formulations demonstrated properties closely matching the native vitreous.
• Both hydrogels were biocompatible in rabbits, maintaining optical clarity and physiological intraocular pressure.
• Retinal layers remained intact with normal electroretinography, and hydrogels exhibited controlled swelling.

Conclusions:

• The developed hydrogels show significant potential as artificial vitreous humor replacements.
• Further in vivo studies in larger animal models (mini-pigs) are warranted for extended duration evaluation.
• The observed swelling behavior suggests a mechanism potentially shared with the native vitreous humor.