Textile multifilament biomaterials: surface modification by N₂ jet particle projection towards improved topography

Foreign Body Reaction (FBR) is a critical issue when polyester textiles are used as medical implants to perform hernia repair, stenosed artery replacement or aneurysm pathology treatment. Whatever the application, the natural porosity of textile materials tends to induce exaggerated biological tissue in-growth after implantation. This mechanism can prevent the implant from remaining flexible and should be limited. It has been shown in literature that one potential strategy to limit the FBR process is to increase the surface roughness of the implanted material, as fibroblasts proliferate slowlier on irregular surfaces. The purpose of this study was to investigate the potential of modifying the topography of textile surfaces using a particle projection technology. A supercritical N2 jet was used to spray corundum particles on multi-filament PET woven surfaces. The impact of the particles created local filament ruptures on the treated surfaces towards hairiness increase. The influence of the jet projection parameters such as pressure, standoff distance (SoD), particle size and mass flow rate on the textile surface roughness was investigated. Two constructions were considered for comparison purpose (plain weave constructions characterized by 34 and 28 weft yarns/cm). The results show that under certain projection conditions, particles can generate a layer of frayed fibers on the textile surface. It comes out that regular hairiness is obtained on the sample surface with following set up adjustment parameters: pressure of 900 bars, SoD of 400 mm and a particle mass flow rate of 0.6 g/s. The interaction of the treated surfaces with mesenchymal stem cells (MSC) was then assessed in vitro in order to identify how hairiness may modify the adhesion (at 24 h) and the proliferation (at 72 h) of the seeded cells. The results show that the obtained hairiness of treated textile surfaces helps limiting cell proliferation in contrast to non-treated surfaces.