Chitosan/alginate based multilayers to control drug release from ophthalmic lens

Area of Science:

• Biomaterials Science
• Ophthalmic Drug Delivery
• Polymer Chemistry

Background:

• Controlling drug release from ophthalmic devices is crucial for effective treatment.
• Natural polymers offer biocompatible and tunable platforms for drug delivery systems.
• Existing soft contact lens (SCL) and intraocular lens (IOL) materials require advanced methods for sustained drug elution.

Purpose of the Study:

• To investigate layer-by-layer (LbL) deposition of natural polymers for controlled ophthalmic drug release.
• To evaluate the efficacy of a chitosan-alginate coating on SCL and IOL materials.
• To assess the impact of the coating on the physical properties and drug release kinetics of the lenses.

Main Methods:

• Utilized layer-by-layer (LbL) deposition with chitosan and alginate on silicone-based hydrogel, CI26Y (IOL), and Definitive 50 (SCL) materials.
• Optimized a coating structure: (alginate-CaCl2)/(chitosan+glyoxal) with a final alginate-CaCl2 layer.
• Investigated the controlled release of diclofenac (anti-inflammatory drug) and analyzed lens physical properties.

Main Results:

• The optimized LbL coating demonstrated excellent control over diclofenac release from both SCL and IOL materials for at least one week.
• The coating maintained or improved the physical properties of the lenses.
• The highly hydrophilic (water contact angle ≈ 0) and biocompatible coating potentially enhances user comfort without additional surface treatments.

Conclusions:

• Layer-by-layer deposition of chitosan and alginate provides an effective strategy for controlled ophthalmic drug release.
• The developed coating shows promise for sustained delivery of diclofenac from SCLs and IOLs.
• Further optimization of the coating's chemical composition is necessary for tailoring drug release for different ophthalmic medications.