利用光催化化学精细调控PDA酚-半醌-醌可逆转化模拟解析血管氧化应激环境中PDA涂层的响应行为和应对策略的研究

Polydopamine (PDA) coating is one of the most important surface modification platform materials for cardiovascular biomaterials. But the composition ratio of phenolic hydroxyl -semiquinone radical- quinone is very easy to be affected by sedimentary conditions, storage environment, and service environment. Therefore, its functional repeatability is affected, Which leads to the instability and amphibolic biological safety in the storage environment and the physiological environment for service in vivo. So it is necessary to realize fine regulation of the chemical state of PDA surface technically. On this basis, the key scientific issues concerning the relationship between the composition of PDA phenol-semiquinone-quinone and the function of PDA coating and in vivo service behavior and their regularity are further understood.The aim of this project is to construct the PDA@TiO2 composite film material which can realize the precise reversible control of the chemical state of PDA by means of the photocatalysis of TiO2. The photo-induced redox reaction was microzoned by micrographics, Designing and constructing multi-channel parallel detection pattern Research platform which can realize multi-direction fine regulation of chemical state of PDA, The study reveals the relationship between phenol-semiquinone-quinone structure and composition of PDA coating and its material properties, biological properties, biocompatibility, environmental stability and biological safety and the law of influence. Understanding and solving the disadvantages of unstable surface function and biosafety caused by the influence of deposition condition, Storage environment and service environment on the surface of PDA coatings. Furthermore, it provides important basis for the application of PDA coating,1.batch parallel detection,2.formation of protein/ cell micropatterns， 3.further realization of patterned composite functional modification material construction technology and material research platform.Therefore, it can provide the understanding foundation and technology accumulation for the coating with antioxidant stress function in the surface modification of cardiovascular materials.

聚多巴胺PDA涂层是生物材料表面改性重要的表面修饰平台材料。然而，PDA涂层表面化学构成易受沉积条件/服役环境的影响，导致功能不够稳定，存在生物安全隐患。本项目拟借助TiO2的光催化性构建可逆调控PDA化学状态的PDA@TiO2复合薄膜材料；利用微图形将光引发的氧化/还原反应微区化，构建能实现PDA化学状态多向精细调控的多通道并行检测的图案化研究平台；揭示PDA涂层的酚-半醌-醌结构及组成比例变动影响涂层材料学/生物学特性、生物相容性的规律，认识与解决PDA涂层表面化学状态易受沉积条件、储存环境、体内服役环境的影响所导致的表面功能和生物安全性不够稳定的缺点；并进一步为PDA涂层应用研究提供了“可进行批量并行检测、形成蛋白/细胞等微图形、进一步实现图案化复合功能修饰的材料构建技术与材料研究平台”；为抗氧化应激的PDA@TiO2多功能涂层在心血管材料表面改性中的应用提供认识基础和技术积累。

聚多巴胺（PDA）涂层是生物材料表面改性重要的表面修饰平台材料，本项目针对PDA涂层应用中的结构/功能不够稳定以及在体内生理环境存在的生物安全隐患，借鉴光催化化学和光化学基本技术原理，分别利用两条研究路径（H2O2结合UV辐照处理、UV辐照TiO2处理）模拟体内氧化应激环境ROS对PDA的氧化过程，并实现了对聚多巴胺（PDA）表面化学结构精细调控；从微图案化的多材料通道/氧化进程调控两个方向为搭建多通道微图案并行检测研究平台奠定了基础，并获得了PDA涂层的酚-半醌-醌结构转化特别是半醌组成比例对PDA涂层生物学功能的影响规律；基于铜卟啉（CuTCPP）的双催化仿酶特性，通过其在PDA涂层表面的接枝提高了PDA在体内的氧化应激环境中的结构和功能稳定性，避免了PDA薄膜结构转化带来的负面作用，有效促进组织正常修复，从而为抗氧化应激的多功能PDA涂层在心血管材料表面改性中的应用提供了认识基础和技术积累。