A fully covered self-expandable metallic stent coated with poly (2-methoxyethyl acrylate) and its derivative: In vitro evaluation of early-stage biliary sludge formation inhibition.

The adhesion and deformation behavior of proteins at the inner surface of fully covered, self-expandable metallic stents coated with biocompatible polymers, poly(2-methoxyethyl acrylate) (PMEA) and poly(3-methoxypropyl acrylate) (PMC3A), were analyzed. Model bile solution, proteins, and bacteria were used to unravel the inhibitory ability of the polymer coatings. Adsorbance of proteins and adherence of bacteria were both strongly inhibited by the polymer coatings. Circulation tests were performed under clinical conditions using human bile from patients. Adsorption/deformation of proteins and early-stage sludge formation were inhibited on stent surfaces coated with PMEA derivatives. The present study revealed that early-stage biliary sludge formation on PMEA- and PMC3A-coated stents was suppressed due to the strong resistance of the polymers to protein adsorption/deformation, brought about by intermediate water in hydrated polymer coatings, which is not present in conventional coating materials, such as silicone and polyurethane.

Antithrombotic Protein Filter Composed of Hybrid Tissue-Fabric Material has a Long Lifetime.

There are recent reports of hybrid tissue-fabric materials with good performance-high biocompatibility and high mechanical strength. In this study, we demonstrate the capability of a hybrid material as a long-term filter for blood proteins. Polyester fabrics were implanted into rats to fabricate hybrid tissue-fabric material sheets. The hybrid materials comprised biological tissue grown on the fabric. The materials were extracted from the rat's body, approximately 100 days post-implantation. The tissues were decellularized to prevent immunological rejection. An antithrombogenicity test was performed by dropping blood onto the hybrid material surface. The hybrid material showed lesser blood coagulation than polysulfone and cellulose. Blood plasma was filtered using the hybrid material to evaluate the protein removal percentage and the lifetime of the hybrid material in vitro. The hybrid material showed a comparable performance to conventional filters for protein removal. Moreover, the hybrid material could work as a protein filter for 1 month, which is six times the lifetime of polysulfone.