Tantalum loaded silicone microspheres as particulate emboli

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Medical Device Engineering

Background:

• Silicone microspheres are investigated for medical applications.
• Radiopacity is crucial for visualizing embolic agents.
• Surface modification is key to improving biocompatibility and dispersion.

Purpose of the Study:

• To develop smooth, spherical, radiopaque silicone microspheres.
• To enhance microsphere hydrophilicity through surface grafting.
• To evaluate the potential of these microspheres for particulate embolization.

Main Methods:

• Medical-grade silicone resin cured in poly(vinyl alcohol) dispersion.
• Encapsulation with tantalum powder for radiopacity.
• Surface grafting with 2-hydroxyethyl methacrylate (HEMA) and N-vinyl pyrrolidone (NVP) using gamma radiation.

Main Results:

• Successfully produced smooth, spherical silicone microspheres with tantalum radiopacifier.
• Tantalum-loaded microspheres >1.00 mm diameter were achievable.
• Grafting with a 1:1 HEMA/NVP ratio significantly improved surface hydrophilicity.
• Tantalum-loaded microspheres showed resistance to surface modification.
• Microspheres dispersed in water with surfactants like Tween 20.

Conclusions:

• The developed technique yields radiopaque silicone microspheres suitable for embolization.
• Surface grafting with HEMA/NVP enhances microsphere properties for potential clinical use.
• Further research may explore optimized grafting and in vivo performance.