Preparation And Properties Of Organic Functional Coatings Based On Dopamine Derivatives

Nowadays,more and more diseases have been possible to cure,with the rapid development of medicine,materials science and other technologies.Interventional therapy is one of the most important motheds to treat various diseases.In the wake of development s in the pathological study and the implanted devices clinical complication research,the requirements of the diversified and multi-functionalized implanted devices are becoming more and more urgent.The biocompatibility of the material is one important fa ctor for the clinical efficacy of the implanted devices.Surface modification of the material is one of the important methodes to improve the biocompatibility of the implantes,and it also can reinvest materials with multi-functional.The dopamine-based materials has been wildly used for the surface modification of many kinds of biomaterials,and it can be coated onto various materials.The coating can provide a good platform for various biological molecules immobilization.In this work,the DMA was synthesized by dopamine and methacrylic anhydride.Then the DMA was characterized and analyzed by FTIR,~1H NMR and HRMS,the resultes indicated that DMA was successfully synthesized.Subsequently,the DMA was used with three kinds of amine rich molecules,such as dopamine(DA),hexylenediamine(HMD)and tris(2-aminoethyl)amine(TAEA),to make three coatings,they are SS-DMA+DA,SS-DMA+DMA,SS-DMA+TAEA.The coatings were characterized and analyzed by WCA,surface morphology and PDP.The resultes certified that SS-DMA+TAEA coating had better performance,DMA and TAEA were choose to build the functional coating build for next studies.Then three coatings was established by different proportions of DMA and TAEA,they are SS-DT2.5,SS-DT5 and SS-DT10.The functional coating`s surface properties were characterized and analyzed by SEM,WC A,FTIR,XPS and other methods.The resultes shown that the functional coatings exhibit better hydrophilicity than 316L SS,Michael addition and Schiff base reactions occur between DMA and TAEA.The stability of the coatings were tested and analized by immersion experiments and electrochemical performance,the resultes shown that the coatings had good stability.The blood compatibility of the functional coatings were evaluated and analyzed by the experimentes of fibrinogen adhesion and activation,platelet adhesion and activation,the resultes shown that the coatings could inhibit the fibrinogen and platelet adhesion,and revealed better anticoagulant properties than 316L SS.The cell compatibility of the functional coatings were evaluated by static culture of endothelial cells(EC)and smooth muscle cells(SMC)in vitro,and the resultes shown that the coatings had better cell compatibility than 316L SS.To verify the secondary reactivity o f the platform,the peptides(TK14)was immobilized on the DT5coating surface through chemical graft.The peptides immobilized surface was characterized by FTIR,WCA and XPS,the resultes shown that the peptides was successfully immobilized on the surface.The blood compatibility and cell compatibility of the peptides immobilized surface were also evaluated,and the data shown that the peptides enhanced EC adhesion and proliferation and the same time inhibited SMC proliferation.All the resultes shown that the functional coatings can be used as a secondary reaction platform for biological material functionalization.In summary,the DMA synthesized by this work have the capacity to form stable coatings on metal materials with functional group rich substances,through the Michael addition and Schiff base reactions.DMA/TAEA coatings had better surface topography,and the surface functional groups can be control through the mol ratio of DMA/TAEA.Meanwhile,the DMA/TAEA functional coatings had good stability,better anticoagulation blood properties and cell compatibility.Furthermore,the functional groups on the surface can be used to immobilize peptides,such as the peptides TK14,and the activity of the peptides can be good remained.This study could provide a method for organic groups functional coatings via dopamine derivative and amine rich molecules,and the organic groups on the surface can be used for biomolecules immobilization.The organic groups functional coatings can be multifunctional platform for diversified and multi-functionalized modification of various implanted devices.