载银活性炭纤维的银离子释放调控及控释机理研究

Conventional methods to treat chronic and acute wounds are prone to infection, and have seriously threatened public health. Therefore, it has important value and social significance to develop new wound dressings for targeted treatment of wound infections. Various silver-loaded dressings have been proven to have good antibacterial properties, but neglect the fastness of silver loading and the risk of cytotoxicity from high concentrations of silver ions. This work is to improve the fastness of silver loading and control release of silver ions of silver-loaded activated carbon fibers by pretreatment of activated carbon fibers and adding degradable coating, clarifying the effects of the surface properties and pore structure of activated carbon fibers on the silver formation, antibacterial properties and silver ion release; the control effect and regularity of degradable coating on silver ion release from silver-loaded activated carbon fibers were studied, and the influence of sodium ion and chloride ion on silver ion release process was discussed. To reveal the correlation between controlled release coating, release environment and antimicrobial properties. The release and controlled release mechanism of silver ion from silver-loaded activated carbon fibers was constructed, to achieve effective silver loading and prevent silver ion from burst release, so prolong the release time and achieve safe long-lasting antibacterial, provide reliable experimental and theoretical basis for the safe application of silver-loaded activated carbon fibers.

治疗慢性和急性伤口的常规手段易发生感染，严重威胁公共健康，因此，研究针对性治疗伤口感染的新型创伤敷料具有重要价值和社会意义。各种载银敷料已证实具有良好的抗菌性能，但忽视了核心问题——载银的牢固程度和释放高浓度银离子带来细胞毒性的风险。本项目通过对活性碳纤维进行预处理和增加可降解控释层的方法对载银的牢固度和银离子释放进行调控，阐明活性碳纤维表面性质、孔结构对纳米银的形成、抗菌性能及银离子释放的影响规律；研究载银活性碳纤维表面涂可降解控释层对银离子释放的控制效果和规律，探讨钠离子、氯离子的存在对银离子释放过程的影响，揭示控释涂层、释放环境与抗菌性能的相关性，构建载银活性碳纤维银离子的释放和控释机理，从而实现有效载银，防止银离子突释，延长释放时间，达到安全长效抑菌的目的，为载银活性碳纤维的安全应用提供可靠的实验依据和理论基础。

含银敷料在临床应用中有个较为常见的不良反应——银质沉着，其是指释放的银离子形成黑色的硫化银，常聚集于汗腺、毛囊等部位；另外体外细胞实验也显示过高的浓度银有细胞毒性。本项目采用对活性碳纤维进行预氧化和预活化处理和在载银活性碳纤维表面增加控释覆膜和涂层的方法对载银的牢固度和银离子释放进行调控。根据本项目技术制备的载银敷料可以有效降低以上两个不良反应的风险：一是将银粒子更多载在活性碳纤维的微孔内，避免太多的银同时释放导致毒性；二是在载银活性碳纤维上覆上水凝胶/聚乳酸涂层，可以在控制银释放速度的同时给伤口修复提供微湿的环境。本项目阐明了活性碳纤维表面性质、孔结构对纳米银的形成、抗菌性能及银离子释放的影响规律；研究了载银活性碳纤维表面控释覆膜和涂层对银离子释放的控制效果和规律；初步探讨了钠离子、氯离子的存在对银离子释放过程的影响；通过以上研究，揭示材料表面性质和结构、控释涂层，以及释放环境与抗菌性能的相关性，构建载银活性碳纤维银离子的释放和控释机理，从而实现有效载银，防止银离子突释，延长释放时间，达到安全长效抑菌的目的，为载银活性碳纤维的安全应用提供可靠的实验依据和理论基础。