Novel bio-elastomers as coating materials for metallic coronary stents

LUCILA NAVARRO; DIANA-ELENA MOGOSANU; DAVID SCHAUBROECK; PETER DUBRUEL

Encuentro; Belgium Polymer Group Annual Meeting 2015; 2015

Aim Biocompatible polymeric coatings for the endothelialization of metallic stents are desired, as stent corrosion can lead to the serious risks for both the surrounding tissue and the stent itself. For the surrounding tissue, the release of metallic ions could impart a high inflammatory reaction, while the stent itself can break due to loss of mechanical stability. For this purpose, novel poly (polyol sebacate)-derived polymers were chosen for investigation. Synthesis and in-depth characterization lead to promising results for the use of these materials. Furthermore, electrospinning was used to create coatings of the above obtained polymers for metallic stents. Methods All reagents were purchased from Sigma-Aldrich and used as received. The molar ratio of reagents was varied in order to tune the mechanical properties of the materials. For comparison reasons and more insight into the reaction, the synthesis was performed via 2 ways: the conventional bulk polymerization and the microwave polymerization. The reagents were mixed in both cases at high temperatures for different reaction times. Films were fabricated and characterized from a physico-chemical and mechanical perspective. Electrospinning of the obtained polymers was performed in order to provide a coating for the metallic stents. Results The polycondensation reaction performed in the present study yielded slightly yellowish but transparent soft elastomers. IR and NMR studies confirmed the structure of the polymers; mechanical testing demonstrated the tunability of this type of elastomers. In vitro biodegradability studies were conducted in PBS buffer at different pH values. The electrospun mats were characterized for their mechanical properties. The fiber diameter varied from 500 nm to 2 µm. Future work will include in vitro biocompatibility studies of the polymer films and of the electrospun mats with endothelial cells. Conclusions In the present study we have successfully synthesized biodegradable materials and developed scaffolds with tunable mechanical properties and good potential biocompatibility for tissue engineering applications.