Photocrosslinked Mucoadhesive Hyaluronic Acid Hydrogel for Transmucosal Drug Delivery

Area of Science:

• Biomaterials Science
• Drug Delivery
• Nanotechnology

Background:

• Drug delivery to the central nervous system is challenging due to the blood-brain barrier (BBB).
• Mucoadhesive formulations aim to increase drug residence time at the application site.
• Hyaluronic acid tyramine (HATA) hydrogels offer potential for enhanced mucoadhesion.

Purpose of the Study:

• To characterize the physicochemical and mucoadhesive properties of photocrosslinked HATA hydrogels.
• To evaluate the impact of crosslinking on hydrogel stability and mucoadhesion.
• To establish a foundation for optimized nasal drug delivery systems.

Main Methods:

• Rheological methods, nanoindentation, and contact angle goniometry were employed.
• Confocal microscopy with a novel 'photon count per pixel' parameter assessed stability and mucoadhesion.
• Ex vivo porcine olfactory tissues were used to evaluate mucoadhesion.
• Drug release studies utilized BSA-labeled rhodamine in low-swelling hydrogels.

Main Results:

• Photocrosslinked HATA hydrogels (1% and 2% w/v) demonstrated stable mucoadhesive properties (16.5–18 photon counts per pixel).
• Uncrosslinked HATA formulations showed significant photon count loss (50–71%).
• Optimal mucoadhesion was achieved with 1 minute of photoirradiation, correlating with Young's modulus and mucoadhesive forces (0.263–0.701 mN mm⁻²).

Conclusions:

• Crosslinking is crucial for enhancing the stability and mucoadhesion of HATA hydrogels.
• Optimized HATA hydrogels show significant potential for targeted nasal drug delivery.
• Further research can build upon these findings for advanced drug delivery systems.