Optimization of the structure of polyurethanes for bone tissue engineering applications.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Polyurethanes are versatile polymers with potential applications in bone tissue engineering.
• Controlling polyurethane properties, particularly hard segment content, is key to tailoring their performance for specific biomedical applications.

Purpose of the Study:

• To synthesize and characterize aliphatic poly(ester-urethanes) with varying hard segment content.
• To evaluate the impact of hard segment content on polyurethane surface properties and biocompatibility for bone tissue engineering.

Main Methods:

• Synthesis of polyurethanes using poly(epsilon-caprolactone) diol, 4,4'-methylenebis(cyclohexyl isocyanate), and ethylene glycol.
• Characterization using modulated differential scanning calorimetry (mDSC), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and static contact angle measurements.
• In vitro biocompatibility assessment using human bone-derived cells (HBDC).

Main Results:

• Increasing hard segment content led to changes in macromolecule order, increased phase separation, higher urethane moiety content, and enhanced surface hydrophilicity.
• Polyurethane surface properties varied gradually with hard segment content.
• In vitro studies showed improved proliferation of human bone-derived cells (HBDC) with increased hard segment content, but a decrease in osteogenic potential.

Conclusions:

• Polyurethane hard segment content significantly influences surface properties and in vitro cellular response.
• Optimizing hard segment content is critical for balancing cell proliferation and osteogenic differentiation in bone tissue engineering scaffolds.
• These tailored polyurethanes show promise for bone tissue engineering, but further research is needed to fully elucidate their in vivo performance.