基于贻贝仿生构建高效抗菌及良好血液相容性的聚胺-酚表面

目的 赋予血液接触类材料优异的表面抗菌性能。方法 受天然贻贝黏附现象的启发，通过多巴胺（Dopamine,DA）、ε-聚赖氨酸（ε-Poly-L-lysine,ε-PL）、高碘酸钠（SodiumPeriodate,NaIO4）构建一种简易、快速的聚胺-酚涂层（ε-PL@PDA），同时利用ε-PL丰富的氨基质子化形成的阳离子，实现表面高效抗菌的目的。其中DA和ε-PL通过共价交联形成酚胺聚合物，酚胺共同介导基底材料黏附形成涂层。通过傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）、场发射扫描电镜（SEM）、椭圆偏光、氨基定量、水接触角（WCA）等材料学表征评价ε-PL@PDA涂层的理化性能；通过菌落计数法、细菌活/死染、液体法等细菌实验评价涂层抗菌性能；通过内皮细胞黏附与增殖实验评价其细胞相容性；通过血小板黏附与激活及半体内血液循环实验验证其血液相容性。结果 材料学表征结果证明，ε-PL@PDA富氨基涂层成功制备，同时ε-PL的浓度大小会影响涂层的沉积过程；细菌实验表明，ε-PL@PDA涂层具备优异的抗菌性能，当ε-PL质量浓度为3 mg/mL时，对大肠杆菌和表皮葡萄球菌的抑制...

Mussel Mimicking Polyamine-Phenol Surface with Efficient Antibacterial Properties and Good Hemocompatibility

In recent years, blood contact devices have brought great convenience to clinical treatments, but they are severely restricted due to bacterial-related infections. Bacteria-related infections not only lead to partial dysfunction of the devices, but also cause a series of complications such as bacteremia and inflammations, which may threaten the patient''s life. For purpose of enhancing the antibacterial properties of the blood-contact materials, a simple and rapid polyamine-phenol coating (ε-PL@PDA) was constructed by dopamine (Dopamine, DA), ε-Poly-L-lysine (ε-PL), and sodium periodate (Sodium period, NaIO4) on the basis of the natural mussel adhesion phenomenon and mechanism in this study. At the same time, the ε-PL@PDA coating utilized the cations formed by the protonation of abundant amino groups of ε-PL to realize the purpose of high-efficiency antibacterial properties. DA and ε-PL formed phenolic amine polymers through covalent crosslinking, and then jointly mediated the adhesion of substrate materials to form the coating. Firstly, the base material (316L SS) was soaked in ammonia water, hydrogen peroxide, and hot water for 1 hour according to the volume ratio of 1∶1∶3, and then washed by RO, UP, and absolute ethyl alcohol respectively. DA (3 mg/mL), NaIO4 (3 mg/mL) were prepared with UP, and ε-PL was configured in proportions of 0.3, 3, and 30 mg/mL. They were mixed uniformly according to the volume ratio of 1∶1∶1, then immersed in the surface of the 316L SS, and reacted for 3 hours at room temperature to obtain the ε-PL@PDA coating. According to the different feeding ratios of ε-PL, they were named as ε-PL/0.3@PDA, ε-PL/3@PDA, ε-PL/30@PDA coatings respectively. The physical and chemical properties of ε-PL@PDA coatings were evaluated by material characterizations such as FTIR, XPS, SEM, ellipsometry, amino group quantification, and WCA. The antibacterial properties were evaluated by the colony counting method, liquid method and fluorescent staining of live/dead bacteria. The adhesion and proliferation of endothelial cells were used for evaluating the cytocompatibility. The adhesion and activation of platelets, as well as the semi-in vivo blood circulation assay were used to confirm the hemocompatibility. The material characterization results of FTIR, XPS, WCA and amino group quantification demonstrated the successful construction of the ε-PL@PDA coatings, and they contained richer amino groups than the PDA coating. The results of ellipsometry test indicated that the concentration of ε-PL could affect the efficiency of reaction, and the high concentration might interfere with the deposition of the coating. Relevant bacterial experiments certified that different concentrations of ε-PL@PDA coatings exhibited excellent antibacterial properties. When the concentration of ε-PL was 3 mg/mL, the antibacterial rates on E.coli and S.epidermidis exceeded 91%, which could beneficially reduce the incidence rate of bacterial infections. The results of the adhesion and proliferation experiments of endothelial cells demonstrated that with the increase of the concentration of ε-PL, the coatings displayed no significant toxic and side effects, possessing great cytocompatibility. The adhesion and activation of platelets and semi-in vivo blood circulation experiment results indicated that the coatings could not aggravate coagulation and formation of thrombus at the concentrations of 3 and 30 mg/mL, compared to 316L SS. The ε-PL@PDA coating can significantly improve the antibacterial ability without affecting the cytocompatibility and hemocompatibility. Therefore, this effective, practical, and applicable surface antibacterial strategy may assist in resolving the issues of bacterial infections of clinical blood contact devices.