Engineering Drug-Eluting Ocular Bioadhesive "OcuTAPE" via Tannic Acid-Mediated Nanoparticle Bridging

Area of Science:

• Biomaterials Science
• Nanotechnology
• Ophthalmology

Background:

• Integrating nanoparticles (NPs) into hydrogels for drug-eluting bioadhesives is challenging.
• Existing ocular adhesives have limitations in retention, mechanical properties, drug release control, and usability.

Purpose of the Study:

• To present a generalizable strategy using tannic acid (TA) for dynamic NP integration into hydrogels.
• To develop a clinically relevant ocular patch (OcuTAPE) for sustained drug delivery and tissue sealing.
• To demonstrate the versatility of TA-bridging for different nanocomposite bioadhesives.

Main Methods:

• Utilized tannic acid (TA) for its multifunctional binding capacity to bridge drug-loaded NPs and hydrogels via hydrogen bonding.
• Developed OcuTAPE, an ocular patch incorporating PEG-based micelles (MCs) for dexamethasone (Dex) release.
• Engineered a second model using PLGA NPs in a GelMA-TA hydrogel for tissue regeneration applications.

Main Results:

• Achieved synthesis-free NP incorporation and versatile nanocomposite designs.
• OcuTAPE demonstrated high toughness (≈4000 kJ m⁻³), rapid wet tissue adhesion, and sustained Dex release over five weeks.
• In vivo studies showed OcuTAPE conformed to ocular biomechanics, retained on eyes, and exhibited biocompatibility and anti-inflammatory effects.

Conclusions:

• TA bridging is a robust strategy for engineering drug-eluting nanocomposite bioadhesives.
• OcuTAPE represents a clinically relevant model for sustained ocular drug delivery and tissue repair.
• The TA-bridging approach offers a versatile platform for developing advanced biomaterials for regenerative medicine.