Construction of NO-releasing coating on PET via layer-by-layer self-assembly.

Nitric oxide (NO) releasing coating is promising for implantable medical devices due to the role of NO in the vascular system. In the study, a multilayered NO-releasing coating was constructed via layer-by-layer (LBL) self-assembly to improve the hemocompatibility of poly(ethylene terephthalate)(PET). A keratin-based NO donor (KSNO) was synthesized and used as a negatively-charged monolayer. Polyethyleneimine (PEI) acted as a positively-charged monolayer. The LBL coating has an adjusted KSNO payload capacity, achieving a tunable NO release in the presence of ascorbic acid (Asc). The coated PET film (n = 5) selectively promoted the proliferation of endothelial cells, while suppressing the excessive proliferation of smooth muscle cells. Furthermore, the coated film demonstrated excellent biocompatibility, along with antibacterial, antioxidant, and anti-inflammatory activities. To the best of our knowledge, it is the first time that a biomacromolecular donor of NO has been used as a monolayer for LBL self-assembly.