Plasma-Mediated Immobilization of Antibody with PEG as Spacer for Enhanced Endothelial Cell Adhesion and Proliferation

Immobilization of anti-CD34 antibody is proven to be an effective strategy to accelerate reendothelialization and thereby lower the thrombosis of blood contacting grafts. To realize highly efficient immobilization of anti-CD34 antibody, an argon cold plasma-mediated graft process was developed with PEG as spacer arm in this study. In this process, the 316L stainless steel (316LSS) model substrate was first coated with ethylene vinyl acetate copolymer (EVA) followed by argon plasma treatment and PEG400 modification (EVA-PEG). The EVA-PEG was further ignited by argon plasma and then the anti-CD34 antibody was immobilized. XPS measurement indicated the successful immobilization of the EVA and the anti-CD34 antibody molecules. Compared with the anti-CD34 antibody anchored without PEG, the immobilized EVA-PEG-anti-CD34 antibody exhibited better capturing efficiency (increase about 1-fold) of specific antigen. Consequently, the endothelial cell attachment (before 12 h) and proliferation (1~4 days) were significantly improved. Further study showed that this EVA-PEG-anti-CD34 coating could reduce blood coagulation. Therefore, this cold plasma-mediated graft process with PEG spacer arm developed here is a promising strategy to immobilize antibody with higher bioactivity for rapid reendothelialization of the cardiovascular implants.