Development of Resorbable Phosphate-Based Glass Microspheres as MRI Contrast Media Agents

Area of Science:

• Biomaterials Science
• Materials Chemistry
• Medical Imaging

Background:

• Resorbable phosphate-based glasses (PBG) are promising biomaterials.
• Developing PBG with controlled properties is crucial for advanced applications.
• Investigating metal oxide modifiers (Fe, Cu, Mn) for tailored functionalities.

Purpose of the Study:

• To synthesize and characterize resorbable PBG microspheres using flame spheroidization.
• To evaluate the structural, chemical, and degradation properties of these microspheres.
• To assess their potential as MRI contrast agents by measuring relaxation rates.

Main Methods:

• Flame spheroidization to produce solid and porous PBG microspheres.
• Characterization using SEM, XRD, EDX, and NMR.
• In vitro degradation studies over 28 days.
• MRI relaxivity measurements (R1 and R2) at 1.5 T and 7 T.

Main Results:

• Dense and porous PBG microspheres with varying metal oxides were successfully fabricated.
• Degradation studies showed no significant differences in mass loss, particle size, or pH.
• Manganese-based PBG microspheres exhibited significantly enhanced R2 and R1 relaxation rates compared to iron and copper variants.
• Enhanced relaxivity attributed to paramagnetic manganese ions.

Conclusions:

• Resorbable PBG microspheres can be effectively produced via flame spheroidization.
• Manganese-doped PBG microspheres demonstrate potential as MRI contrast agents.
• The porosity of PBG microspheres offers opportunities for drug delivery, advancing theranostic capabilities.