Polycarbonate polyurethane containing ascorbic acid provides antioxidant bioactivity for tissue engineering heart valve scaffolds

Research background and material design: The development of artificial heart valves faces multiple challenges: the complex environment of natural valves can easily lead to a decrease in valve durability. The current strategy includes performing anti calcification treatment on pericardial tissue, developing durable polymers that can inhibit oxidative degradation and stress cracking, and introducing absorbable scaffolds through tissue engineering to form stable functional tissue. In this context, a study published in the Journal of Biomedical Materials Research Part A synthesized and characterized a polyurethane containing ascorbic acid, aiming to provide a biodegradable scaffold with antioxidant properties as a substitute for tissue-engineered heart valves (TEHV).

The study blended polycarbonate ascorbic acid polyurethane (PCAU) with polycarbonate polyurethane urea (PCUU) to prepare microporous scaffolds, and evaluated the effects of PCAU on mechanical properties, degradation, cell viability, calcification, and bacterial adhesion in vitro. At the same time, the in vivo native tissue response was evaluated in a subcutaneous model of juvenile rats.

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Key findings and data

Research shows that when PCAU and PCUU are blended in a ratio of 25:75 (PCAU-25), their mechanical properties are similar to PCUU.

; However, blends with higher PCAU concentrations have insufficient mechanical strength. PCAU-25 exhibits stronger reactive oxygen species (ROS) inhibition ability, faster degradation rate, and reduced calcification and bacterial adhesion in vitro. In the subcutaneous model of juvenile rats, both PCUU and PCAU-25 groups showed negligible calcification after 4 weeks; However, the PCAU-25 group showed more pronounced cell infiltration and immune response, which research suggests may be related to its accelerated degradation. Subsequently, PCAU-25 was made into a polymer valve stent and underwent basic mechanical and fluid dynamic performance evaluations, which showed that its function was similar to previously reported PCUU valves. These findings provide a conceptual validation for a novel polyurethane formulation that combines ascorbic acid to achieve antioxidant biological activity, and demonstrate its feasibility for conversion into functional TEHV scaffolds.

Significance for the polymer additive industry

This study introduces ascorbic acid into the polycarbonate polyurethane main chain or blend system, providing new ideas for the antioxidant design of medical polymer materials.

. In the field of medical and health materials, especially in tissue engineering scaffolds and implantable devices, oxidative degradation is one of the key factors affecting long-term stability. By blending, the material is endowed with antioxidant bioactivity while maintaining machinable mechanical properties, which has reference value for weather stability and the application of antioxidants in medical polymers. It is worth noting that although the accelerated degradation of PCAU-25 in the study reduced calcification, it also triggered a more pronounced immune response, suggesting the need for precise regulation of the formulation when balancing degradation rate and tissue compatibility. In addition, the material showed similar performance to PCUU in valve stent fluid dynamics testing, indicating that blending modification did not sacrifice basic mechanical functions, providing a reference path for the development of medical polymer formulations in the future. Overall, this study demonstrates the potential of ascorbic acid functionalized polyurethane in heart valve tissue engineering and highlights the importance of antioxidant strategies in the design of medical polymer scaffolds. For industry professionals interested in medical materials, medical polymers, weather stability, and antioxidants, this work provides an example of combining bioactive molecules with polyurethane systems, which deserves further attention in formulation design and performance evaluation.

Information source:An Ascorbic‐Acid Containing Poly(Carbonate) Urethane With Antioxidant Bioactivity for Application in Heart Valve Scaffold Development， Organized by Herun Chemical.