Hybrid Stents Based on Magnetic Hydrogels for Biomedical Applications

Area of Science:

• Biomaterials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Hydrogels possess advantageous mechanical and physical properties, making them promising biomaterials due to high biocompatibility.
• Magnetic hydrogels, incorporating magnetic nanoparticles, offer responsiveness to external magnetic fields and prevent nanoparticle leakage, enhancing safety in biomedical applications.

Purpose of the Study:

• To fabricate, characterize, and evaluate a prototype magnetic hydrogel hybrid stent for magnetic hyperthermia treatment.
• To assess the safety and efficacy of magnetic hydrogels in preventing nanoparticle leakage.
• To examine the heating efficiency and temperature control capabilities of the magnetic hybrid stent.

Main Methods:

• Magnetic hydrogel was produced using alginate and magnetic nanoparticles in a calcium chloride bath for external gelation.
• Nanoparticle leakage was quantified over 15 days at varying concentrations (1-8 mg mL⁻¹).
• Hybrid stents were tested in an agarose phantom and ex vivo tissue under magnetic hyperthermia conditions (30 mT, 765 kHz).

Main Results:

• Increased magnetic nanoparticle concentration (1-8 mg mL⁻¹) resulted in near-zero iron oxide nanoparticle leakage after 15 days.
• Magnetic hybrid stents demonstrated excellent heat generation and facile temperature control by adjusting nanoparticle concentration (2-8 mg mL⁻¹).
• Evaluation in phantom and ex vivo models confirmed efficient heating under hyperthermia conditions.

Conclusions:

• The developed magnetic hybrid stents are safe for biomedical applications due to minimal nanoparticle leakage.
• These stents show significant potential for localized thermal distribution in treating cancers or restenosis in hollow organs.
• This study presents a promising approach for spatially controlled thermal therapies using magnetic hydrogels.