胶原纤维接枝杨梅单宁负载纳米Ag的制备及其抗菌性能研究

Preparation, Characteristics and Antibacterial Activity of Nano-Ag loaded on Bayberry Tannin-grafted Collagen Fiber

摘要:

以胶原纤维（CF）接枝杨梅单宁（BT）为载体，制备了一种新型纳米银（nAg）抗菌剂（CF-BTx-nAg）。BT为一种天然的酚类化合物，将此“桥梁分子”接枝到胶原纤维上，不仅可以提高Ag的负载量，还能控制纳米Ag的粒径及分布。通过扫描电镜（SEM）、红外（FTIR）、透射电镜（TEM）、X射线衍射（XRD）、X射线光电子能谱（XPS）等手段对该抗菌剂的物化性能进行表征，发现该抗菌剂具有规则的纤维结构，纳米Ag颗粒的平均粒径为3.25 nm且分散均匀。抗菌实验结果表明，不同BT接枝度的CF-BT-nAg对大肠杆菌均具有较好的抑制能力，其中CF-BT0.2-nAg的抑制能力最强。当CF-BT0.2-nAg与浓度为~105 cfu/mL的大肠杆菌菌悬液在310 K、150 r/min下连续培养（Ag浓度为8 ?g/mL），4h后已检测不到活细菌的存在，而相同条件下CF-BT0.05-nAg和CF-BT1.0-nAg分别需要8 h和12 h。CF-BT0.2-nAg对大肠杆菌的最小抑菌浓度（MIC）为4 ?g Ag/mL，表现出优良的抗菌性能。且CF-BT0.2-nAg至少可重复使用5次。胶原纤维接枝杨梅单宁负载纳米银材料可作为一种新的、有效的抗菌剂。

Abstract:

A novel antibacterial agent (CF-BTx-nAg) of nanometer silver (nAg) was synthesized by using bayberry tannin (BT) grafted collagen fiber (CF) as supporting. Bayberry tannin (BT), a typical natural polyphenol, was grafted onto the CF surface to improve the loading capacity and to control the size as well as the dispersion of Ag nanoparticles. The main physical and chemical properties of this antibacterial agent were characterized by means of Scanning Electron Microscopy (SEM), Fourier Transform-Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS) and X-ray Diffraction (XRD). It was found that this antibacterial agent is in highly ordered fibrous state. The average diameter of Ag nanoparticles is 3.25 nm and the nanoparticles are homogeneously dispersed. Antibacterial experiments demonstrated that CF-BTx-nAg exhibited high antibacterial activity. When cell suspensions of Escherichia coil solutions with concentration of ~105 cfu/mL was cultivated with CF-BT0.2-nAg at 310 K under shaking (150 r/min, conc. of Ag = 8 μg/mL), the number of living cells went down to zero within 4 h, while it was 8 h and 12 h for that of CF-BT0.05-nAg and CF-BT1.0-nAg, respectively. The minimal inhibitory concentration (MIC) of CF-BT0.2-nAg against E. coli was 4 μg Ag/mL. In addition, CF-BT0.2-nAg can be re-applicated effectively at least five times. These facts suggested that CF-BT-nAg could be used as a new and effective antibacterial agent.