Polyurethane porous scaffolds (PPS) for soft tissue regenerative medicine applications

Tissue engineering requires suitable polymeric scaffolds, which act as a physical support for regenerated tissue. A promising candidate might be polyurethane (PUR) scaffold, due to the ease of the PUR properties design, which can be adjusted directly to the intended purpose. In this study, we report a successful fabrication of porous polyurethane scaffolds (PPS) using solvent casting/particulate leaching technique combined with thermally induced phase separation. The obtained PPS had comparable chemical structure to native PUR, which was confirmed by FTIR and HNMR analyses. The performed DSC study determined a similar T _g of the obtained PPS to native PUR (−38 °C). The analysis of TEM micrographs revealed that PPS had a homogenous structure. The studied PPS interactions with canola oil, distilled water, saline solution and phosphate-buffered saline after 3 months of incubation revealed that these materials have stable character in these media. The significant decrease of contact angle from 68° for native PUR to 54° for PPS was noted, as well as the decrease of mechanical properties (T _Sb ~ 1 MPa and ε _b ~ 95% of PPS were comparable to the native aorta tissue of T _Sb ~ 0.3–0.8 MPa and ε _b ~ 50–100%). Through SEM analysis, the morphology of the PPS was determined: the porosity was 87% and the pore sizes in the range of 98–492 µm. The biological studies revealed that the obtained PPS are sensitive to microorganisms such as Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli and that they are biocompatible with the 3T3 NIH cell line. In summary, the obtained PPS scaffolds may be a suitable material for soft tissue engineering like blood vessels.