Waterborne polyurethane 3D scaffold containing PLGA with controllable degradation rate and anti-inflammatory for potential applications in neural tissue repair

Currently, implanting tissue engineering scaffold is one of the treatment methods for regeneration of damaged tissue. The matching degradation rate of the scaffolds with the regenerated rate of the damaged zone is a big challenge in tissue engineering. Here, we have synthesized a series of biodegradable waterborne polyurethane emulsions and fabricated three-dimensional (3D) connected porous polyurethane scaffolds by freezing-dry. The degradation rate of the scaffolds were controlled by adjusting the relative ratio of poly e-caprolactone (PCL) and poly(lactic-co-glycolic acid) (PLGA) in the soft segment. The degradation rate of the scaffolds gradually accelerated with the increase of the relative proportion of PLGA. By co-culture with BV2 microglia, the scaffolds promoted the differentiation of BV2 into anti-inflammatory M2 phenotype rather than pro-inflammatory M1 phenotype as the increase of the proportion of PLGA. When the BV2 cells were stimulated with lipopolysaccharide (LPS), the scaffolds with higher PLGA ratio showed much stronger anti-inflammatory effect. Then, we demonstrated that the scaffolds could promote the PC12 neurons to differentiate into neurites. Therefore, we believe that the polyurethane scaffold has a promising potential application in neural tissue repair.