Cu^(Ⅱ)-loaded polydopaminecoatingswith in situ nitric oxidegenerationfunctionforimproved hemocompatibility

NO is the earliest discovered gas signal molecule which is produced by normal healthy endothelial cells,and it has many functions,such as maintaining cardiovascular homeostasis,regulating vasodilation,inhibiting intimal hyperplasia and preventing atherosclerosis in the blood system.Insufficient NO release is often observed in the pathological environment,for instance atherosclerosis.It was discovered that NO could be released from the human endogenous NO donor by many compounds,and these methods can be used for the treatment of certain diseases in the blood system.In this work,a series of copper-loaded polydopamine(PDA)coatings were produced through self-polymerization time for 24,48 and 72 h.The chemical composition and structure,coating thickness and hydrophilicity of the different copper-loaded PDA coatings surfaces were characterized by phenol hydroxyl quantitative,X-ray photoelectron spectroscopy,ellipsometry atomic force microscopy and water contact angles.The results indicate that the thickness and the surface phenolic hydroxyl density of the PDA coatings increased with the polymerization time.This copperloaded coating has glutathione peroxidase-like activity,and it has the capability of catalyzing NO releasing from GSNO.The surface of the coating showed desirable hemocompatibility,the adhesion and activation of platelets were inhibited on the copper-loaded coatings.At the same time,the formation of the thrombosis was also suppressed.These copper-loaded PDA coatings could provide a promising platform for the development of blood contact materials.