In situ crosslinking temperature-responsive hydrogels with improved delivery, swelling, and elasticity for...

Area of Science:

• Biomaterials Science
• Medical Devices
• Polymer Chemistry

Background:

• Endovascular embolization is crucial for preventing cerebral aneurysm hemorrhage.
• Current embolic agents like coils or polymers have limitations in filling efficacy and delivery complexity.

Purpose of the Study:

• To develop an easily deliverable, in situ forming hydrogel for complete aneurysm occlusion.
• To investigate a hydrogel system utilizing temperature-responsive polymers and chemical crosslinking.

Main Methods:

• Synthesized temperature-responsive polymers (poly(NIPAAm-co-cysteamine) and poly(NIPAAm-co-cysteamine-co-JAAm)) with thiol groups.
• Formulated hydrogels by mixing polymer solutions with poly(ethylene glycol) diacrylate (PEGDA).
• Evaluated hydrogel properties including delivery time, gelation kinetics, mechanical strength, and stability under flow in a model aneurysm.

Main Results:

• One formulation (30 wt % PNCJ20 + PEGDA) demonstrated a delivery time exceeding 220 seconds.
• The hydrogel achieved high mechanical strength (G' > 6000 Pa) within 30 minutes.
• The set hydrogel maintained its shape and volume under simulated physiological flow conditions.

Conclusions:

• The developed hydrogel, leveraging both physical and chemical crosslinking, shows potential as an effective embolic agent.
• This water-based material offers improved delivery and complete occlusion for saccular aneurysms.
• Further investigation is warranted to validate its efficacy and safety for clinical application.