Poly(fumaric-co-sebacic anhydride). A degradation study as evaluated by FTIR, DSC, GPC and X-ray diffraction

Area of Science:

• Polymer science
• Materials science
• Biomaterials engineering

Background:

• Polyanhydrides are biodegradable polymers used in drug delivery.
• Understanding poly(fumaric-co-sebacic anhydride) [P(FA:SA)] degradation is crucial for controlled release applications.
• Hot melt encapsulation is a common method for creating polymer microspheres.

Purpose of the Study:

• To investigate the degradation behavior of P(FA:SA) microspheres.
• To identify the degradation products, specifically low molecular weight oligomers.
• To correlate degradation extent with pH conditions.

Main Methods:

• Microsphere preparation via hot melt encapsulation.
• Characterization using Fourier-transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and X-ray diffraction.
• Degradation studies in acidic, neutral, and basic buffer solutions.

Main Results:

• The emergence of low molecular weight oligomers was observed during P(FA:SA) copolymer degradation.
• Degradation was significantly accelerated under basic pH conditions.
• Minimal differences in degradation rates were found between neutral and acidic buffers.
• Consistent results across multiple characterization techniques validated the findings.

Conclusions:

• P(FA:SA) microsphere degradation is pH-dependent, with faster rates at basic pH.
• The degradation process results in the formation of low molecular weight oligomers.
• Integrated characterization methods provide a comprehensive understanding of polyanhydride degradation.