Synthesis of RGD-peptide modified polyester-urethane) urea electrospun nanofibers as a potential application for vascular tissue engineering

The development of a biomimetic surface which is able to promote endothelialization is fundamental in the research for blood vessel substitutes to overcome the formation of thrombi or hyperplasia. In the present work, the fabrication of acrylamide-terminated glycine-arginine-glycine-aspartic peptides (Ac-GRGD) modified poly(ester-urethane) urea (PEUU) nanofibrous mats via electrospinning technique followed by covalent immobilizing method for improving its endothelialization was successfully achieved. Series of PEUU based polymers including PEUU, PEUU with t-butoxycarbonyl group (PEUU-Boc), and PEUU-amino group (PEUU-NH2) were synthesized by a two-step solution polymerization and a de-protection process. The PEUU-RGD as-prepared nanofibrous mat was characterized using different techniques, such as, scanning electron microscopy, solide-state C-13 CP-MAS nuclear magnetic resonance, and stress-strain test. In addition, to motivate cell adhesion and proliferation, PEUU nanofibers mat was immobilized by coupling of Ac-GRGD. The results present that incorporation of Ac-GRGD peptide improved the mechanical properties and does not have negative effect on the morphology and the structure of PEUU nanofibers. From cell viability and cell morphology results, the prepared PEUU-RGD nanofiber mats are cytocompatible. Interestingly, the immobilized PEUU-RGD nanofibers possess lower hemolysis rate and an improved inhibition of platelet adhesion. Overall, Ac-GRGD peptides immobilized PEUU nanofibrous mats may have a potential application for vascular tissue engineering. (C) 2017 Elsevier B.V. All rights reserved.