Bilayer Electrospun Polyurethane Membrane With Tunable Elastomeric Properties for the Treatment of Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia is a rare condition characterized by the development of a defect in the diaphragm during early embryogenesis. For the most severe cases, when the diaphragmatic defect is large, the gap is currently closed by a prosthetic patch made of e-PTFE (Gore-Tex) materials, which lack sufficient elasticity, causing early rupture of stitches and subsequent hernia recurrence. In this study, we introduce a novel thermoplastic polyurethane membrane designed to accommodate the child's growth. This film/fiber bilayer membrane, produced in a single continuous electrospinning process by varying the flow rate, exhibits a smooth surface to prevent adhesion of the tissues on the abdominal side and a rough surface to promote adhesion of the diaphragm muscle on the thoracic side. Mechanical properties of the membrane were evaluated under various deformation modes, including uniaxial tensile tests and equibiaxial tensile tests by the bubble inflation technique. We demonstrated the ability to tune the elastic modulus by adjusting the thickness of the film and fibers, achieving greater stretchability than specified for supporting child growth and respiration both in uniaxial and inflation tests. Moreover, in vitro biological tests showed that the membrane promotes cellular colonization without pro-inflammatory effect, making it a promising candidate to replace the currently used prosthesis.