Preparation and characterization of a novel antimicrobial film dressing for wound healing application

Antibacterial activity and good mechanical properties are some of the characteristics required for an appropriate film dressing. A novel polymer blend was developed for wound healing application. Twenty-four formulations using the polymers chitosan, poly(vinyl alcohol) and/or ɛ-Polylysine and the plasticizer glycerol were designed using factorial design and then the films were prepared by the casting/solvent evaporation method. Seventeen films were obtained among the twenty-four proposed formulations that were characterized by Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Mechanical properties, such as tensile strength (σ), elongation at break (ɛ) and Young’s modulus (Y) as well as antibacterial properties were determined. The best candidate was then further analyzed with regard to porosity, Water Vapor Transmission Rate (WVTR), swelling and cytotoxicity experiments. The results showed a film with semi-occlusive characteristics, good mechanical properties and no toxic. Incorporation of ɛ-Polylysine increased antibacterial activity against gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria.

合适的伤口敷料薄膜需兼具抗菌活性与优良力学性能。本研究开发了一种用于伤口愈合应用的新型聚合物共混体系。以壳聚糖、聚乙烯醇（poly(vinyl alcohol)）和/或ε-聚赖氨酸（ɛ-Polylysine）以及增塑剂甘油为原料，通过析因设计构建了24组配方，并采用流延/溶剂挥发法制备薄膜。在24组预设配方中，最终获得17组可表征的薄膜，通过场发射扫描电子显微镜（Field Emission Scanning Electron Microscopy, FE-SEM）与傅里叶变换红外光谱（Fourier Transform Infrared Spectroscopy, FTIR）对其进行表征。测定了其拉伸强度（σ）、断裂伸长率（ɛ）、杨氏模量（Y）等力学性能以及抗菌性能。随后对最优候选薄膜进一步开展孔隙率、水蒸气透过率（Water Vapor Transmission Rate, WVTR）、溶胀性能与细胞毒性实验分析。结果显示，该薄膜具备半封闭性特征、优良力学性能且无细胞毒性。引入ε-聚赖氨酸可提升其对革兰氏阴性菌大肠杆菌（Escherichia coli）与革兰氏阳性菌金黄色葡萄球菌（Staphylococcus aureus）的抗菌活性。