pH-Sensitive sulfamethazine-based hydrogels as potential embolic agents for transcatheter vascular embolization

Area of Science:

• Biomaterials Science
• Vascular Surgery
• Radiology

Background:

• Vascular embolization uses embolic agents to block blood vessels for treating diseases.
• Current liquid embolic agents like Onyx and cyanoacrylate have limitations including toxic solvents and catheter entrapment.
• There is a need for safer, more effective liquid embolic agents for clinical use.

Purpose of the Study:

• To design and evaluate a novel, biocompatible, injectable, radiopaque liquid embolic agent.
• To address the limitations of existing embolic agents.
• To assess the feasibility of a pH-sensitive polymeric hydrogel for vascular embolization.

Main Methods:

• A new pH-sensitive hydrogel copolymer, PEG-PUSSM (poly(ethylene glycol)-poly(urethane sulfide sulfamethazine)), was synthesized.
• The embolic solution containing PEG-PUSSM and iohexol demonstrated a sol-to-gel transition triggered by decreased pH.
• Biocompatibility, rheological properties, and in vivo embolization efficacy were evaluated in rat and rabbit models.

Main Results:

• The PEG-PUSSM hydrogel showed good biocompatibility and rapid in vivo gelation with high stability after subcutaneous injection in rats.
• Successful occlusion of renal arteries was achieved in rabbit kidney models, leading to ischemic changes up to 32 days.
• Gelation within hepatic arteries was confirmed in rabbit liver models, indicating potential for liver embolization.

Conclusions:

• The developed pH-sensitive PEG-PUSSM hydrogel is a promising biocompatible and radiopaque embolic agent.
• This novel hydrogel effectively achieved vascular occlusion in preclinical models.
• PEG-PUSSM demonstrates significant potential for future vascular interventional therapies.