Structural and Biomechanical Characterization of Human Intestinal Tissue for the Design of a Polyvinyl Alcohol (PVA) Membrane Device for Temporary Stoma Closure

The management of intestinal stomas remains a significant clinical challenge due to associated complications and their impact on patients’ quality of life. Current devices are often limited by their inability to adequately match the biomechanical and structural properties of intestinal tissue, thereby reducing their physiological compatibility. In this context, the development of temporary and reversible solutions requires a comprehensive understanding of intestinal tissue behaviour. This study aims to provide an integrated characterization of human intestinal tissue to support the design of a biomedical device for temporary stoma closure based on a polyvinyl alcohol (PVA) membrane. Human ileum and colon samples were analysed through a combination of histological, biochemical and biomechanical approaches to investigate tissue structure, extracellular matrix composition and mechanical response, with the ultimate goal of defining design criteria for a temporary, mechanically compliant and non-adhesive intestinal interface. The results revealed clear segment-specific differences in both structure and mechanical behaviour. Distal segments exhibited increased muscular thickness, whereas the ileum showed greater submucosal expansion. Mechanical testing highlighted a non-linear, anisotropic and viscoelastic behaviour, with higher stiffness and strength observed in colonic tissues compared to the ileum. Extracellular matrix components, particularly collagen, contributed to tissue mechanics within a complex and multifactorial framework, while structural features such as the taenia further enhanced load-bearing capacity. Overall, these findings indicate that intestinal tissue behaviour arises from the interplay between architecture, composition and structural organization, rather than from single parameters alone. From a bioengineering perspective, these results provide a comprehensive basis for the design of biomaterials for intestinal applications and support the potential use of PVA-based membranes on temporary stoma closure devices. In particular, their tuneable mechanical properties, combined with a low cell-adhesion profile, may help reduce undesired tissue attachment and enable controlled and reversible device–tissue interaction.