Dopamine-Assisted Deposition Of Polyethyleneimine(PEI)for Efficient Surface Functionalization

Mussel-inspired polydopamine (PDA) has been very attractive and many amine-or thiol-containing biomolecules have been immobilized via quinone mediated Schiff base or Michael addition reactions.12However, the classic approach using N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS) for biomolecule immobilization was restrained due to the limited density of amines on polydopamine. Herein, we developed a facile dip-coating strategy for obtaining primary amino-rich surfaces. Using the facile dip-coating strategy, polydopamine can be easily deposited onto a wide range of metallic, inorganic materials, and gain interests also in the field of biomaterials. It was found that the PDA-modified surface significantly enhances HUVEC adhesion, proliferation, and migration, release of nitric oxide(NO), and secretion of prostaglandin I2(PGI2). Additionally, the PDA-modified surface showed a remarkable ability to decrease the adhesion and proliferation of HUASMCs.In this job, a facile dip-coating strategy for preparing a dopamine-polyethyleneimine (PEI) copolymer film on316L stainless steel was developed.It aimed to achieve the amplifiable and adjustable ammo densities by adjusting the input concentration of polyethyleneimine in the method of the copolymerization system. Considering the blood compatibility test and cell culture evaluation, the further functionalized surface by immobilizing heparin or VEGF on hemocompatibility and cell growth was investigated.Besides, the potential use of such coating on biomolecule immobilization and the relative bio-function was also tested. Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS) demonstrated the successful coating formation. Compared with PDA coating, such coating presented higher ratio of nitrogen due to the introduction of PEI. Combining blood test and cell culture,how the before and after heparin/VEGF grafted dopamine-polyethyleneimine copolymer film effected blood compatibility and growth behavior of endothelial cells and smooth muscle cells was investigated.In addition, quartz crystal microbalance (QCM-D) experiments showed that PDA surface via EDC method would adsorb less heparin with only about288ng/cm2, while PEI deposited surface presented higher heparin immobilization amount, reaching up to830ng/cm". With the adjustment of the components and the concentration of polyethyleneimine in the copolymerization system, the quantity can be adjustable.The research includes the affect of the dopamine-polyethyleneimine copolymer films before and after grafting of heparin on endothelial cells, smooth muscle cell’s adhesion and proliferation,the affect of the dopamine-polyethyleneimine copolymer films before and after grafting of VEGF on endothelial progenitor cells’s adhesion and proliferation.Results show that dopamine-polyethyleneimine copolymer film can inhibit smooth muscle cell’s adhesion and proliferation in some extent,After heparin grafted dopamine polyethyleneimine copolymer films can also inhibit smooth muscle cell adhesion and proliferation. But dopamine-polyethyleneimine copolymer film also inhibited endothelial cells and endothelial progenitor cell adhesion and proliferation.In summary, the dopamine-polyethyleneimine copolymer film can become a potential way to the surface modification of new multifunctional cardiovascular implants.