细菌纤维素基多层复合功能敷料的设计、可控制备及性能研究

Currently, serious skin damage caused by burn wounds, scald wounds and chronic wounds with several complications such as infection represents a major and persistent burden in orthopedics and dermatology. One of the effective strategies is developing novel dressings with many functions such as anti-infection and promoting healing. Based on the latest concepts of designing functional dressings with multilayer structure and our previous research work, a novel bacterial cellulose (BC) based multilayer composite functional dressing will be fabricated by in situ membrane-liquid interface synthesis method with hydroxypropytrimethyl ammonium chloride chitosan (HACC) and type I collagen (COLI) introduced into the fibril network structure of BC successively. The physical and chemical performance of dressing will be investigated. Properties of dressing such as hemostatic, remove toxins, prevent adhesion performance, anti-infection and promoting healing will be evaluated by in vitro biological experiments and full skin damage infection model of rats. Furthermore, the effect of introduction of HACC and COLI to structure and biological properties of BC will be studied, the synergistic effects of HACC and COLI will be analyzed, and the interdependent relationship between the multilayer structure, HACC and COLI content and the biological performance of dressing will also be revealed. The findings of this study will be used to explore a new design principle of functional dressing and application of BC based functional material for tissue engineering and regenerative medicine.

烧伤、烫伤及慢性创伤造成的皮肤严重受损难以修复，并易引起感染等并发症，是当前矫形外科和皮肤科难以治愈的疾患之一。开发具有抗感染、促愈合等多种功能的新型敷料是解决这一临床问题的有效途径。基于功能敷料多层结构设计的最新理念和本研究团队的前期研究工作基础，本项目拟采用原位膜液界面复合法，将壳聚糖季铵盐(HACC)和I型胶原(COLI)引入到细菌纤维素(BC)网络结构中，以获得HACC/COLI/BC多层复合功能敷料。考察敷料的理化性能，通过体外生物学实验及大鼠全皮损伤感染模型评价其止血、清除毒素、防粘连性能、抗感染性能和促愈合能力。在此基础上，研究HACC和COLI的引入对BC三维网络结构、生物学性能的调控规律及协同作用机理，揭示多层结构、HACC及COLI含量与敷料的生物学性能之间的依存关系。本项目研究结果将为新型功能敷料的设计和BC基功能材料在组织工程和再生医学领域的应用提供新的思路。

烧伤、烫伤及慢性创伤造成的皮肤严重受损难以修复，并易引起感染等并发症，是当前矫形外科和皮肤科难以治愈的疾患之一。开发具有抗感染、促愈合等多种功能的新型敷料是解决这一临床问题的有效途径。基于细菌纤维素(BC)良好的敷料特性，本项目采用原位膜液界面培养法、浸泡法、共沉积法等方法制备了壳聚糖季铵盐/BC （HBC）、壳聚糖季铵盐/I型胶原/BC（CHBC）、负载杆菌肽的I型胶原/BC（BA@CBC）和载铜聚多巴胺/BC（Cu2+@PDA/BC）四种功能敷料。研究了各组分对敷料理化性能的影响，探讨了生物活性物质I型胶原与抗菌剂壳聚糖季铵盐、杆菌肽的协同作用，考察了所得功能敷料处理感染创面的能力。.本项目的主要结论如下：.1. 采用原位复合法制备了HBC抗菌敷料，抗菌剂HACC对BC的生物合成有一定的影响。当用量为3 mg/mL时（HBC-2组），HBC-2敷料维持BC典型的纳米孔径结构，具有良好的热稳定性、高吸水率和优异的抗菌性能，并无细胞毒性。.2. 采用原位膜液界面培养法制备了CHBC功能敷料。该敷料具有良好的热稳定性、吸水性、保水性和透湿性。HACC赋予功能敷料良好的抗菌性能；Col-I提高了功能敷料的细胞相容性。能够在抑制感染的同时，能够促进表皮组织和毛囊生成、 I型胶原沉积以及创面快速愈合。.3. 采用原位膜液界面复合法和浸泡法制备了BA@CBC功能敷料。Col-I的引入能够减缓BA的释放，避免突释。该功能敷料能够消除感染、减轻炎症反应并促进创面快速愈合。.4. 采用共沉积法制备了Cu2+@PDA/BC抗菌敷料。铜离子用量为10 mM时，Cu2+@PDA/BC-2能够消除感染和炎症，促进I型胶原沉积、毛囊和血管生成以及创面愈合。