Preparation and Properties of Polyvinyl Alcohol/ε-Polylysine Hydrogel Wound Dressing

Composite hydrogels PVCL with antibacterial properties were prepared by freeze-thawing method by introducing ε-polylysine(ε-PL) and citric acid (CA) into polyvinyl alcohol (PVA) aqueous solution. The structure and properties of PVCL were characterized by Fourier transform infrared spectroscopy (FT-TR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), universal tensile testing machine and swelling capacity. The biological properties of the composite hydrogels were characterized by antibacterial test, hemolysis test and cytotoxicity test. Results showed that the mechanical properties of PVA hydrogels were improved by adding CA. Compared with pure PVA hydrogel, the tensile strength of hydrogel was increased by 66.7% (from 1.8 MPa to 3.0 MPa), and the elongation at break increased by 19.8% (from 355.9% to 426.5%). However, the addition of ε-PL could reduce the mechanical properties of the hydrogels. The highest swelling rate of the composite hydrogel was 293.7%. ε-PL provided excellent antimicrobial activity for composite hydrogels. The antibacterial rate increased with the increase of ε-PL content, and the highest antibacterial rate against E.coli and S.aureus was close to 100%. In addition, PVCL had excellent hemocompatibility and cytocompatibility.