Preparation and properties of artificial auricles based on PVA/BNC composites

The key to auricle reconstruction is to achieve a biomechanical fit between the implanted material and the natural tissue. So far, an ideal auricle substitute has not been found. In this study, bacterial nanocellulose (BNC) homogenate was added into polyvinyl alcohol (PVA) aqueous solutions of different concentrations, and the freeze-thaw method was used to form PVA/BNC composite materials with both high elastic flexibility and high mechanical strength via physically cross-linking. The physical and chemical properties and cytocompatibility of the composites were characterized. The results show that the material has the characteristics of high water absorption, low swelling ratio, as well as high toughness, elasticity and suture strength. The maximum compressive modulus reaches 6.98 ± 0.49 MPa, which matches the biomechanics of natural auricle tissue. The maximum suture strength reaches 7.06 ± 0.33 N, which fully meets the needs of clinical suture. Addition of BNC promotes the adhesion, growth and proliferation of cells on the surface of the material, giving the PVA/BNC composite material higher cell density and vitality. All the results show that the PVA/BNC composite is a promising biomaterial for artificial auricles.